Common controls used in Lazarus forms.

comctrls.pp contains classes and types like those found in the Delphi comctrls unit.

The following components are added to the Lazarus IDE:

Common Controls Tab

TTrackbar
TProgressBar
TTreeView
TListView
TStatusBar
TToolBar
TCoolBar
TUpDown
TPageControl
TTabControl
THeaderControl

The following components are added but not displayed on the component palette:

TToolButton
TTabSheet

This file is part of the LCL package.

Represents permissible results for a hit test.

THitTest is an enumerated type with values that represent permissible results for a hit test (position of a mouse click etc relative to objects on a form). Values from THitTest are stored in the THitTests set type.

The action was above the coordinates for the control. The action was below the coordinates for the control. The action was not near the control checking for the event. The action was on the control checking for the event. The action was on a button in the control. THitTests - set of THitTest. Represents the style used for a panel on a status bar.

TStatusPanelStyle is an enumerated type representing the style used for a panel on a status bar. TStatusPanelStyle is the type used to implement the Style property in TStatusPanel, and used in widgetset classes which initialize or update a status bar panel.

The panel contains Text. The panel uses an owner-drawn style (generally implemented in an event handler). Enumerated type with the bevel styles used on status bar panels.

TStatusPanelBevel is an enumerated type with values which represent bevel styles used on status bar panels. TStatusPanelBevel is the type used to implement the Style property in TStatusPanel.

No bevel is drawn on a panel. Drawn using a lowered bevel style. Drawn using a raised bevel style. Lists the possible parts that make up a status panel.

TPanelPart is an enumerated type listing the possible parts that make up a status panel.

Panel part contains text with text alignment. Panel parts contains a bevel style. Panel part contains a width value. Set type used to store TPanelPart values.

TPanelParts is a set type used to store TPanelPart values.

Class reference used to create new instances of TStatusPanel.

TStatusPanelClass is the type returned by the GetPanelClass method in TStatusBar. The class reference is used in the CreatePanel method in TStatusBar to create a new panel for the control.

Implements a panel displayed in TStatusBar.

TStatusPanel is a TCollectionItem descendant which implements panels used in TStatusBar. Instances of the class are created by and stored in a TStatusPanels collection in a TStatusBar control. Use the properties in the panel to control its appearance, size, and textual content.

Gets the value for the Alignment property. New value for the property. Sets the value for the Bevel property. New value for the property. Sets the value for the Style property. New value for the property. Sets the value for the Text property. New value for the property. Sets the value for the Width property. New value for the property. Field used by Widgetset classes. Do not use it in the LCL. Field used by Widgetset classes. Do not use it in the LCL. Gets the value displayed as the name for the collection item.

GetDisplayName is an overridden String function which returns the value displayed as the name of the collection item. The value in the Text property is used as the return value when it is not an empty string (''). Otherwise, the inherited GetDisplayName method is called to get the return value.

TCollectionItem.DisplayName Value displayed as the name for the collection item. PanelChanged - method for dealing with a status panel, one or more of whose parts has changed. SetIndex saves the old index value, checks that the supplied value is different and then calls inherited method. TCollectionItem.Index Create - constructor for TStatusPanel: sets default width, alignment and bevel, calls inherited Create and loads into StatusBar. TCollectionItem.Create Collection which owns the status panel. Destroy - destructor for TStatusPanel: calls inherited Destroy and removes itself from the StatusBar. TCollectionItem.Destroy Assign copies text, width, alignment, bevel and style properties from Source if it is of correct type, otherwise calls inherited Assign (which will probably raise an exception). TPersistent.Assign Class instance with the values stored in the status panel. The StatusBar that contains this StatusPanel Status bar where the panel is displayed. Alignment - whether left- or right-justified or centered. Only supported on Windows. The type of Bevel for the display. Only supported on Windows. Introduces BiDiMode support not present in the ancestor class. Introduces BiDiMode support not present in the ancestor class. Style - whether text or something drawn by the owner. Text - the string for display in the StatusBar. The Width of this panel on the StatusBar. TStatusPanels - the collection of Status Panels in this StatusBar. Gets the value for the indexed Items property. TCollection.GetItem Value for the property. Ordinal position for the requested collection item. Sets the value in the indexed Items property. TCollection.SetItem Ordinal position for the collection item stored in the method. New value for the collection item. GetOwner returns a Status Bar overriding the inherited method. TPersistent Persistent object that owns the status panel. Ensures that observers are notified when he specified collection item has been changed. TCollection Collection item for the notification. Constructor for the class instance. Create - constructor for TStatusPanels: calls inherited Create and attaches itself to StatusBar. TCollection.Create The control where the status panel is displayed. Adds a new TStatusPanel instance to the collection.

Calls the inherited Add method and casts the result to TStatusPanel for use as the return value. Calls the UpdateHandleObject method in StatusBar to ensure that an update sequence is started when the handle for the status bar has been allocated.

TCollection.Add Status panel added in the method. Provides indexed access to the TStatusPanel items in the collection. TCollection.Items Ordinal position for the collection item. The StatusBar to which this collection of Status Panels belongs. TSBCreatePanelClassEvent - generic event handling procedure for creating a Status Bar panel class. Specified an event handler used to draw a panel in a status bar.

TDrawPanelEvent is the type used to implement the OnDrawPanel property in TStatusBar.

Status bar for the event notification. Panel drawn by the event handler. Drawing area for the event notification. TStatusBar - a strip along the bottom of a form for displaying information on current status.

TStatusBar - a strip along the bottom of a form for displaying information on current status. The bar may consist of a single SimplePanel in which case the displayed text is contained in SimpleText.

However if SimplePanel is false, then there can be multiple panels or sub-sections of the status bar whose properties are described in Panels.

The property SimpleText can be assigned in code to display the value of some variable, such as the position of the Splitter in the example.

Sets the value for the Panels property. New value for the property. Sets the value for the SimpleText property.

Notifies the widgetset class of the value change when a handle has been allocated and SimplePanel is set to True.

New value for the property. Sets the value for the SimplePanel property. New value for the property. Sets the value for the SizeGrip property. New value for the property. CreateWnd calls inherited method, then fixes handles if needed. TWinControl.CreateWnd DestroyWnd calls inherited method and frees handles. TWinControl.DestroyWnd Loaded calls inherited method and fixes handles if needed. TWinControl.Loaded UpdateHandleObject - updates all panel parts that have been changed. CalculatePreferredSize calls inherited method then supplies its own values if any are missing. TControl.CalculatePreferredSize Sets the value in the BiDiMode property.

Ensures that all panels in the status bar update their alignment to match the new value for the property. Calls UpdateHandleObject to ensure that an update sequence is started for the control when its handle has been assigned.

TControl.BiDiMode New value for the property. CreatePanel - returns a created Status Panel. Status panel creates in the method. CreatePanels - returns a set of created panels. Status panels created in the method. GetPanelClass - returns a class of status panel. Class type used for status panels. DoSetApplicationHint - specifies a hint string and returns True if successful. Displays the hint for the status bar. DoHint shows the hint text for the control and returns True when successful. Uses the OnHint event handler. DrawPanel calls the OnDrawPanel event handler if assigned. Panel to draw in the method. Display rectangle for the drawing operation. LMDrawItem - LCL message handler for drawing the item on the current canvas. Message handled in the method. Performs actions needed to apply the layout policy in AMode.

Calls BeginUpdate to reduce the number of refreshes needed when updating panels in the status bar. Adjusts the width of all items in the Panels collection using the factor in AXProportion. The value in AYProportion is ignored in the method. Calls EndUpdate prior to exit from the method.

No actions are performed in the method when AMode contains a TLayoutAdjustmentPolicy value other than lapAutoAdjustWithoutHorizontalScrolling or lapAutoAdjustForDPI. Layout policy applied in the method. Horizontal sizing factor applied to panels in the status bar. Vertical sizing factor applied to panels in the status bar. Constructor for the class instance.

Create is the constructor for TStatusBar. It calls the inherited Create method, and initializes a number of local variables, including:

AutoHint
Canvas
ControlStyle
Color
Align
AutoSize
SimplePanel

TComponent.Create TWinControl.Create Owner of the class instance. Destroy - destructor for TStatusBar: frees canvas and panels, then calls inherited Destroy. TWinControl.Destroy TComponent.Destroy Updates the panel at the specified position in the Panels for the status bar.

InvalidatePanel renders the panel with specified index non-valid. Calls UpdateHandleObject to ensure that the widgetset class is notified of the change to the specified panel.

No actions are performed in the method when the PanelParts argument is an empty set ([]). Ordinal position for the panel affected in the method. Panel parts affected in the method. BeginUpdate - starts the update process. EndUpdate - finishes the update process. ExecuteAction: if required action is a Hint-related, sets the Hint in place, otherwise calls inherited method. TComponent.ExecuteAction Gets the ordinal position for the panel at the specified coordinates.

GetPanelIndexAt gets the ordinal position for the panel at the specified coordinates. The return value is -1 when Panels have not been defined in the status bar. No actions are performed in the method when Panels is empty.

GetPanelIndexAt uses the display rectangle for the control to determine in the specified coordinates are within one of the Panels defined for the control. When True, each of the items in the Panels collection are examined to determine if the point is within a specific panel. The ordinal position for the panel is assigned as the return value.

Ordinal position for the status panel, or -1 when no panel is located at the specified coordinates. Horizontal coordinate to locate in the Panels for the status bar. Vertical coordinate to locate in the Panels for the status bar. SizeGripEnabled - returns True if the size-grip (an area at the bottom of the statusbar where a mouse can grip to change the size) is enabled. UpdatingStatusBar - returns True if the status bar is being updated. True if the status bar is being updated. The Canvas where the Panels for the StatusBar are are Painted. Specifies the placement of the control inside its Parent.

Align is a TAlign property which specifies how the control is aligned to its parent control. The default value for the property is alBottom in TStatusBar.

TControl.Align Indicates if a hint is automatically shown when the mouse hovers over the status bar.

The default value for the property is False.

Indicates if the control is automatically resized to fill the area on its aligned edge.

The default value for the property is True in TStatusBar.

TControl.AutoSize The background color of the control.

The default value for the property is clDefault or clBtnFace (depending on the UseCLDefault compiler define).If the color is clDefault , the result will need to be passed through GetDefaultColor to resolve clDefault to an actual TColor value.

Convenience routines which obtain the color by resolving clDefault and ParentColor are also provided as TControl.GetColorResolvingParent and TControl.GetRGBColorResolvingParent.

TControl.Color Collection with the TStatusPanel instances defined for the control.

Panels is a collection used to store TStatusPanel class instances added to the status bar. Panels are significant when the SimplePanel property is set to False; when SimplePanel contains True, the status bar displays the value in SimpleText across the entire width for the status bar.

Use CreatePanel to create a new status panel displayed on the status bar. Or use the editor provided in the Lazarus IDE Object Inspector to maintain the items in the Panels collection at design-time.

SimpleText - a character string containing the information to be displayed in the Status Bar.

SimpleText - a character string containing the information to be displayed in the Status Bar. This is displayed if SimplePanel is true; otherwise the information in Panels is displayed.

Indicates if a single panel is displayed in the status bar with the text in SimpleText.

SimplePanel is a Boolean property which indicates if a single panel is displayed in the status bar with the text in SimpleText

If True, the value of SimpleText is displayed; if False, the contents of the individual Panels is displayed.

Contents can be adjusted with a stringlist editor that pops up when the ellipsis (...) next to Panels is selected and allows insertion of an arbitrary number of sub-panels with their own strings.

Displays a sizing grip used to resize the parent form.

SizeGrip is a Boolean property which indicates if a sizing grip (or grabber) is visible for the status bar. The sizing grip is a triangular shape displayed at the bottom-right of the status bar, and provides an alternate way to resize the parent form using the mouse. It presents a larger mouse target than a window border.

The default value for the property is True, and indicates that the sizing grip is visible.

Setting a new value for the property causes the widgetset class to be notified of the change if the handle has been allocated for the control.

Use SizeGripEnabled to determine if the sizing grip is enabled in the control.

TCustomForm.BorderStyle TControl.Parent Indicates the System font is used for the control. This is used to provide VCL-compatibility in widgetset classes. Indicates if the control is visible.

Allows the control, and all of its children, to be displayed or hidden. Visible is set to True by Show , or to False by Hide. Calling these methods is equivalent to setting the Visible property.

The default value for the property is True in TStatusBar.

TControl.Visible Event handler signalled to get the class used to create new panels in the status bar.

OnCreatePanelClass is signalled (when assigned) in the CreatePanel method to get the class used to create new panels in the status bar. Assign an object procedure using the signature in TSBCreatePanelClassEvent to the property to override the value provided by the GetPanelClass method.

Event handler signalled to draw a panel in the status bar.

OnDrawPanel is an event handler used to draw the specified panel on the status bar. OnDrawPanel is signalled (when assigned) from the DrawPanel method. Assign an object procedure using the signature in TDrawPanelEvent to render the specified panel to the desired rectangle in the status bar.

Event handler for showing a hint when required. Contains values which can be assigned to the Flags property in TCustomPage. Reflects the status or state for the handle used in a custom page control. Handle for the page has been added to the notebook. Handle for the page is being added to the notebook. Removing the page handle from the notebook. Inserting the page handle into the notebook. Set type used to store TPageFlag enumeration values.

TPageFlags is the type used to implement the Flags property in TCustomPage.

The base class for TTabSheet.

TCustomPage is a TWinControl descendant which implements the base class for the tabbed pages found in notebooks. TCustomPage provides properties used to maintain the order and visibility of the page, and event handlers signalled when the page is hidden or displayed.

Using Multi-Page Controls Sets the value for the ImageIndex property.

Notifies the widgetset class of changes to properties in the custom page.

New value for the property. Sets the value for the TabVisible property. New value for the property. Registers the widgetset class used for the class instance. Handles the LM_PAINT message for the control.

WMPaint is an overridden method in TCustomPage which handles the LM_PAINT message for the control. It calls the inherited method to render the control. No actions are performed in the method if the Parent is a TCustomTabControl descendant and the class instance is not the current page in the Parent control.

TWinControl.WMPaint Message handled in the method. Sets the Parent control for the custom page. TControl.SetParent New value for the Parent property. Contains flag values that represent the status or state for the handle in the custom page control.

Values in Flags are normally added or removed when changes are performed in a control which uses the page control class instance. See TPageFlag for more information about enumeration values and their meanings.

Handles the CM_HITTEST control message.

CMHitTest checks the type for the Parent control to determine whether the Message is ignored or forwarded to the inherited method. When Parent is a TCustomTabControl descendant, the class instance must be the active page in the parent control. When it is not, the Message result is set to 0 and the message is ignored. Otherwise, the inherited method is called to handle the Message.

TControl.CMHitTest Control message handled in the method. Handles the CM_VISIBLECHANGED message for the control.

Calls the inherited method to handle a focus change and update the control state. If the control is Visible, the DoShow method is called to signal the OnShow event handler (when assigned). Otherwise, DoHide is called to signal the OnHide event handler (when assigned).

TWinControl.CMVisibleChanged Control message handled in the method. Gets the value for the PageIndex property. Value for the property. Sets the value for the PageIndex property. New value for the property. Gets the value for the TabVisible property. Value for the property. Provides support for a TCustomTabControl parent when handling a dialog accelerator key.

Calls the inherited DialogChar method when Parent is not derived from TCustomTabControl.

TWinControl.DialogChar True if message contains an accelerator key handled in the method. Message examined in the method. Performs actions needed when Visible is changed to False.

DoHide is a method used to perform actions needed when the Visible property is changed to False. DoHide signals the OnHide event handler (when assigned).

DoHide is called from the CMVisibleChanged message handler.

Performs actions needed when Visible is changed to True.

DoShow is a method used to perform actions needed when Visible property is changed to True. DoShow signals the OnShow event handler (when assigned).

DoShow is called from the CMVisibleChanged message handler.

Updates the Flags property when the Handle for the control is freed.

DestroyHandle is an overridden method used to update the control when its Handle is freed in the widgetset class. DestroyHandle calls the inherited method on entry, and updates the Flags property to exclude the value pfAdded.

TWinControl.Handle TWinControl.DestroyHandle Notifies the widgetset to change the text for the control.

RealSetText is overridden in TCustomPage to notify the widgetset class of the value change when the Parent control is assigned and has a valid Handle. RealSetText calls the inherited method to apply the new value. AdjustSize is called if the widgetset class was notified.

TWinControl.RealSetText TWinControl.Handle TControl.AdjustSize Value used for the Text (Caption) in the control. Constructor for the class instance.

Create is the overridden constructor for TCustomPage, and calls the inherited constructor on entry. Create sets the default values for the style, visibility, alignment and caption in the class instance.

TWinControl.Create Owner of the class instance. Indicates if the Tab key can be used to navigate into or out of the control.

Always returns False in TCustomPage.

TWinControl.CanTab Always returns False. Indicates whether the control is visible.

IsControlVisible is an overridden method in TCustomPage which indicates whether the control is visible.

If AutoSizingAll is set to True, no actions are performed in the method and the return values is True. This allows inactive pages to be considered in the GetPreferredSize method in the parent control.

IsControlVisible calls the inherited method on entry to determine if the Visible property is set to True, and whether the control is visible at design-time. When the Parent control is TCustomTabControl, the value in the PageIndex property must match the value in the parent control.

The return value is True when all of the conditions are satisfied.

TControl.IsControlVisible True when the control is visible. Gets the index number for a visible page within all of the visible pages.

VisibleIndex is an Integer function used to get the ordinal position for the page instance within the list of visible pages for the Parent control.

When Parent is a TCustomTabControl descendant, its TCustomPage instances are examined to find the current class instance. At run-time, only pages with the TabVisible property set to True are considered in the method. At design-time, all pages are examined.

The return value is the relative position in the list of visible pages where the current class instance was found. The return value is -1 if the current page was not found in the Parent control, or when none of the pages in the Parent control are visible.

When Parent is not derived from TCustomTabControl, the return value is always -1.

Ordinal position for the visible page, or -1 when not found or not visible. Ensures that the specified control is derived from TCustomTabControl.

Raises an EInvalidOperation exception when AParent is not derived from TCustomTabControl. Calls the inherited CheckNewParent method when AParent is unassigned or derived from TCustomTabControl.

Raises an EInvalidOperation exception when AParent is not derived from TCustomTabControl. TControl.CheckNewParent Parent control examined in the method. Ordinal position for the page in the parent control.

PageIndex is an Integer property which contains the ordinal position for the page control in its Parent control. Setting a new value for the property causes the Parent control to call its MoveTab method to reorder the pages. This action is performed when the Parent control is descended from TCustomTabControl.

Indicates if the tab in the Parent control is visible.

TabVisible indicates if the Tab in the Parent control is visible.

Changing the value in the property cause the Parent control to be updated to reflect the new value. No actions are performed in the method at design-time, or when the property value is not different than the stored value.

When the Parent control has been assigned and has a handle allocated, the TCustomTabControl in Parent is updated to reflect the new value for the property. When True, the active page in the Parent control is changed to the current page instance if one has not already been assigned in the Parent. The page and its handle are removed from the Tab control when the property value is False.

Use IsControlVisible to determine if the page is currently the active page displayed in the Parent tab control.

Ordinal position for the image associated with the page.

ImageIndex contains the ordinal position in an image list for the image associated with the page instance. The default value for the property is -1 and indicates that an image has not been assigned for the page. The image list is a property available in the Parent control.

Changing the value for the property causes the widgetset class to be notified using its UpdateTabProperties method.

No actions are performed in the method during LCL component streaming, or when the Handle for the control has not been allocated.

Not stored in LCL component streaming for TCustomPage. The value for the Left property is not stored in the LCL component streaming mechanism for TCustomPage. TControl.Left Not stored in LCL component streaming for TCustomPage. The value for the Top property is not stored in the LCL component streaming mechanism for TCustomPage. TControl.Left Not stored in LCL component streaming for TCustomPage. The value for the Width property is not stored in the LCL component streaming mechanism for TCustomPage. TControl.Width Not stored in LCL component streaming for TCustomPage. The value for the Height property is not stored in the LCL component streaming mechanism for TCustomPage. TControl.Height Not stored in LCL component streaming for TCustomPage. The value for the TabOrder property is not stored in the LCL component streaming mechanism for TCustomPage. TWinControl.TabOrder Not stored in LCL component streaming for TCustomPage.

The value for the Visible property is not stored in the LCL component streaming mechanism for TCustomPage.

TControl.Visible Event handler signalled when the page is hidden.

OnHide is a TNotifyEvent property with the event handler signalled when the page is hidden. OnHide is signalled from the DoHide method, and occurs when the value in the Visible property is set to False.

Applications can implement and assign a handler routine to respond to the event notification. The Sender argument contains the TCustomPage instance for the event notification.

Event handler signalled when the page becomes visible.

OnShow is a TNotifyEvent property with the event handler signalled when the page becomes visible. OnShow is signalled from the DoShow method, and occurs when the value in the Visible property is set to True.

Applications can implement and assign a handler routine to respond to the event notification. The Sender argument contains the TCustomPage instance for the event notification.

Class reference used to create a new TCustomPage instance. Ancestor for the TNBPages class.

TNBBasePages specifies the ancestor for TNBPages, and provides virtual abstract methods used to maintain a list of TCustomPage objects associated with a TCustomTabControl (also called a "notebook"). Use the TNBPages descendant which provides concrete method implementations and additional properties and methods for the purpose.

Gets the ordinal position for the specified page object. Ordinal position for the specified page object, or -1 when not found. Page object to locate in the list. Inserts the specified page at the given position in the list. Ordinal position where the page is inserted. Page object inserted in the method. Deletes the page at the specified position in the list. Ordinal position for the page deleted in the method. Gets the page object stored at the specified position in the list. Page object stored at the specified position in the list. Ordinal position in the list for the requested page object. Constructor for the class instance.

Calls the inherited constructor. Please note: The value in theNotebook is ignored in the method. Use the derived TNBPages class which stores the notebook where the page objects are used.

Notebook (or custom tab control) for the page objects; Ignored in the method. Class reference used to create new instances of TNBBasePages. Implements a list of pages used in TCustomTabControl.

TNBPages is a TNBBasePages descendant which implements a list of pages used in TCustomTabControl.

TNBPages extends the ancestor class to include properties for the TCustomTabControl which owns the list of pages (Notebook), and the internal list used to store the TCustomPage instances (PageList). It implements the abstract virtual methods defined in the ancestor, and provides additional methods to maintain the pages in PageList.

Implements the OnChange event handler for the page list. Implements read access to values for the Strings property.

Read access is redirected to the PageList property. The return value contains the Caption for the TCustomPage instance stored at the specified position in PageList.

TStringList Returns the Caption for the page. Ordinal position for the requested value.

GetCount is an overridden method in TNBPages, and returns the number of items stored in PageList.

Gets the number of pages in the class instance.

GetObject is an overridden method in TNBPages, and redirects indexed object access to the PageList property. The return value is a TObject instance, and must be cast to TCustomPage to access its properties and methods.

Use GetPage to get a page in PageList as a TCustomPage instance.

TStringList Object stored at the specified position. Ordinal position for the object requested in the method. Gets the position in PageList for the specified page. Ordinal position for the page instance, or -1 when not found. TCustomPage instance to locate in the list of pages. Inserts a page instance at the specified position in the page list. Ordinal position in the page list for the inserted value. Page instance inserted into the page list. Deletes the page stored at the specified position in the page list. Ordinal position for the page removed from the page list. Gets the page stored at the specified position in PageList.

GetPage implements the abstract method defined in the ancestor, and is used to get a TCustomPage instance stored at the specified position in PageList. GetPage calls the GetObject method to retrieve the page, and casts it to the TCustomPage type used in the return value.

TCustomPage instance stored at the specified position. Ordinal position in PageList for the requested page. List with the TCustomPage instances for the class instance.

PageList is a read-only TListWithEvent property which contains the TCustomPage instances for the class instance.

PageList includes an OnChange event handler used to perform notifications when values are added, retrieved, or deleted in the list. The private PageListChange method implements the handler, and ensures that new items in the list are parented to the control in Notebook.

Most methods in TNBPages are redirected to PageList to get or set their values.

TListWithEvent TListNotification Provides a reference to the control which owns the pages. Constructor for the class instance.

Create is the constructor for TNBPages, and calls the inherited Create method. It sets up the list of pages for the notebook (tab control).

TObject.Create Control which owns the class instance (and its pages). Destructor for the class instance.

Frees and releases resources allocated to PageList.

Removes all pages stored in the class instance.

Calls Delete until all TCustomPage instances in PageList have been removed.

TStrings.Clear Deletes the page stored at the specified position in the page list. TStrings.Delete Ordinal position for the page removed from the list. Inserts a new page with the given name at the specified position in PageList.

Insert calls the GetPageClass method in NoteBook to get the class reference used to create the new page. The owner of the page instance is the NoteBook control (or its owner when assigned). The value in S is assigned as the Caption in the TCustomPage instance. The InsertPage method in NoteBook is called to store the TCustomPage instance at the position in Index.

TStrings.Insert Ordinal position where the new page is stored. Name (Caption) used for the new page instance. Re-implements an empty page container for TCustomTabControl controls.

TNBNoPages is a TNBBasePages descendant which re-implements the page container for a TCustomTabControl. As the name implies, it does not actually use TCustomPages instances in the container. It removes the methods used to add and maintain the values in the class instance.

TTabChangingEvent - generic event handling method for a change in a notebook Tab. Notebook for the event notification. Indicates if the tab change can be performed. Represents the position for a tab relative to its page.

TTabPosition is an enumerated type with values that represent the position for the tabs in TCustomTabControl relative to its page. TTabPosition is the type used to implement the TabPosition property in TCustomTabControl.

Displays tabs along the top edge of the page. Displays tabs along the bottom edge of the page. Displays tabs vertically along the left edge of the page. Displays tabs vertically along the right edge of the page. TTabStyle - enumerated type for tab style: normal, buttons or flat buttons.

TTabStyle is an enumerated type with values that define the drawing style used for tabs in TCustomTabControl. TTabStyle is the type used to implement the Style property in TCustomTabControl.

Tabs are drawn using the tab style common to manilla file folders. Tabs are drawn as buttons. Tabs are drawn as buttons using a flat (non-raised) appearance. TTabGetImageEvent - generic event handling method for getting an image for a Tab. Object for the event notification. TCTabControlOption - Show the close button on a tab, allow multi-line tabs. TCTabControlOptions - set of TCTabControlOption. TCTabControlCapability - enumerated type containing possible capabilities of a notebook or tabbed control. nbcShowCloseButtons, nbcMultiLine, nbcPageListPopup, nbcShowAddTabButton TCTabControlCapabilities - set of TCTabControlCapability. TDrawTabEvent - generic event handling procedure for drawing a tab with given index at the specified rectangle. Implements the base class for tabbed controls in the LCL.

TCustomTabControl - base class for TTabControl, a series of Tabs along the edge of a display area; selection of a Tab governs the contents of the DisplayRect

A tab control has a series of Tabs and it may or may not contain pages.

Using Multi-Page Controls Notifies the widgetset class when PageIndex has been changed. Notifies the widgetset class when ShowTabs has been changed. Notifies the widgetset class when TabPosition has been changed. Notifies the widgetset class when TabSize has been changed. Notifies the widgetset class when Images has been changed. Gets the value for the ActivePage property.

Uses an internal index value to get the caption for the TCustomPage in the Page property.

Value for the property. Gets the value for the ActivePageComponent property. Value for the property. Gets the value for the DisplayRect property. Value for the property. Gets the value for the MultiLine property. Value for the property. Locates a visible page in the tab control.

FindVisiblePage is used to locate a Page in the tab control with its TabVisible property set to True.

Index specifies the ordinal position in Pages property that is the search locus. FindVisiblePage searches the Page collection in ascending order starting at the position in Index. If a visible page is not found, Page is searched in descending order starting at Index -1.

The return value contains the ordinal position in the indexed Page property where the visible tab was located, or -1 when there are no visible tabs in Page.

Ordinal position for the visible page tab, or -1 when a visible tab is not found. Ordinal position where the search is started. Implements the storage specifier for the ActivePage property.

Always returns False in TCustomTabControl.

Always returns False in TCustomTabControl. Moves the specified page control to the position in NewIndex. Page object moved in the method. New position in the list of pages. Sets the value for the MultiLine property. New value for the property. Sets the value for the Style property. New value for the property. Notifies the widgetset class when a page is moved in the control. Performs action needed when the current page object is removed from the tabbed control. Ordinal position for the page object removed from the tabbed control. Sets the value for the ActivePage property. New value for the property. Sets the value for the ActivePageComponent property. New value for the property. Sets the value for the Images property. New value for the property. Sets the value for the ImagesWidth property. New value for the property. Sets the value for the PageIndex property. New value for the property. Sets the value for the Pages property. New value for the property. Sets the value for the ShowTabs property. New value for the property. Sets the value for the TabHeight property. New value for the property. Sets the value for the ShowTabs property. New value for the property. Sets the value for the TabWidth property. New value for the property. Ensures that the current page has its Visible property set to True.

ShowCurrentPage checks the value in PageIndex to determine if a valid page index has been specified. No actions are performed in the method when PageIndex is less than 0 or greater than PageCount - 1.

ShowCurrentPage gets the TCustomPage instance in Page at the position in PageIndex, and sets its Visible property to True. If the Page is Enabled, it SetFocus method is called.

ShowCurrentPage sets the Visible property in the previously selected Page to False.

Updates control style flags to hide or display pages in the control at design-time. Updates control style flags for the specified page to hide or display the control at design-time. Ordinal position for the Page updated in the method. Notifies the widgetset class when the handle for the image resolution is freed. TApplication.QueueAsyncCall Image list for the event notification. Not used in the method. Not used in the method. Performs actions needed when an image list in the control is changed.

Queued and executed asynchronously by the Application instance.

Pointer to the Data for the asynchronous event. Performs actions needed to apply the specified auto-adjust layout policy. TControl.DoAutoAdjustLayout Gets the class type used to create new page instances in the control. Class type used to create new page instances in the control. Gets the class type used to access a list of pages in the control. Class type used to access a list of pages in the control. Sets the value for the Options property. New value for the property. Notifies the widgetset class when a page handle is added or removed in the control. Page instance with the handle added or removed. Handles the CN_NOTIFY message for the control.

Handles TCN_SELCHANGE and TCN_SELCHANGING notification codes in Message.

Control notification message handled in the method. Creates the Handle for the widgetset object and displays the selected tab and page.

Calls the inherited method on entry. Adds or removes handles for pages on the control. Displays the visible tabs and the active page for the control.

TWinControl.CreateWnd Notifies the widgetset class of the active page when the control Handle is allocated.

Notifies the widgetset class of the value in PageIndex when the control Handle has been allocated.

TWinControl.Loaded Performs actions needed when the active page for the control has been changed.

Performs actions needed when the active page for the control has been changed. Signals the OnChange event handler (when assigned). Called when a new value is assigned to PageIndex.

Performs actions to show or hide pages when the current page is changed.

Change is a method used to performs actions needed to show or hide pages in the tabbed control.

Change calls ShowCurrentPage to display the page in PageIndex, and hide the previously visible page in the tabbed control. Change calls DoChange when the control is not being destroyed, or loaded in the LCL component streaming mechanism.

Change is called from the MoveTab method, and when selection change messages are handled for the control.

Handles page navigation using the Tab key.

KeyDown is overridden in TCustomTabControl to handle use of the Tab key (VK_TAB) to change the active page in the tabbed control.

The Options property must contain the value nboKeyboardTabSwitch to enable the tab switching feature. Pressing Ctrl+Tab switches to the next page by incrementing the PageIndex value. Pressing Ctrl+Shift+Tab switches to the previous page by decrementing the PageIndex value.

If Key is not the VK_TAB virtual key code, the inherited method is called to handle the values in Key and Shift.

TWinControl.KeyDown Virtual key code examined in the method. Key modifier(s) used in the method. Handles an accelerator key for the active page in the tabbed control. TControl.DialogChar True if the accelerator was handled in the active page. Message with the accelerator key examined in the method. Updates the internal page index without triggering an OnChange event. New value for the internal page index. Makes the specified page object the active page in the tabbed control.

ShowControl gets the position for the control specified by the APage argument in the Page property, and makes it the active page in the tabbed control. If the control is not found in Page, the inherited ShowControl method is called to display the control.

ShowControl is provided for Delphi compatibility.

TWinControl.ShowControl Page object to locate and display in the method. IndexOfTabAt returns the index value for the Tab located at the specified client coordinates. Gets the index for the page at the specified client coordinates. UpdateTabProperties - apply all pending changes to the Tab. GetControlClassDefaultSize returns its own defaults, overriding inherited values. TControl.GetControlClassDefaultSize Handles the notification when a component is added to or removed from the control.

Notification is overridden in TCustomTabControl to ensure that resources allocated for the Images property are Nil'd when the component is removed.

TControl.Notification Component for the notification. Operation performed for the component. The active TCustomPage instance for the tabbed control.

ActivePageComponent is a TCustomPage property which indicates the active page component for the tabbed control.

PageIndex is used to access the page instance in Page with the property value. The property value is Nil when PageIndex contains a value that is not in the range 0..PageCount-1.

Setting a new value for the property causes the IndexOf method to be called to locate the value in the list of pages. PageIndex is updated to reflect the position for the specified page, and may contain -1 if pages are not used in the tabbed control.

Use ActivePage to get or set the active page in the control using its Caption.

Caption for the active page in the tabbed control.

ActivePage is a String property which holds the caption for the active page in the control.

The property value is retrieved using values in the PageIndex and Page properties, and contains the Caption property for the TCustomPage instance. The property value is an empty string ('') if PageIndex is not in the range 0..PageCount-1.

Setting a new value for the property causes the indexed Page property to be searched to locate the TCustomPage instance with a Caption matching Value. If a page is found with the specified caption, the SetPageIndex method is called to validate and store the PageIndex, and signal the OnChange event handler when configured in Options. No actions are performed if the new property Value is not used in Page.

A value assigned to ActivePage at design-time is not stored in the LCL component streaming mechanism.

Use ActivePageComponent to read or write the TCustomPage instance that is the active page in the control.

Use Tabs to access the internal page (or tab) list for the control.

TControl.Caption Gets the value for the indexed Page property. Value for the property. Ordinal position for the page object requested in the method. Gets the value for the PageCount property. Value for the property. Updates the control when the specified page is inserted into the page list. Updates the control when the page at the specified position is removed from the page list. Signals the OnChanging event handler prior to updates to PageIndex. Always returns True. Rectangular area used to display information for the tabbed control.

DisplayRect is a read-only TRect property which contains the display rectangle for the tabbed control. The property value contains the TRect instance returned from the TWinControl.GetClientRect method.

TWinControl.GetClientRect TRect Contains the list of pages accessible in the tabbed control.

Tabs is a TStrings property which contains the list of pages for the tabbed control. It is created using the class reference from GetListClass in the constructor. By default, TNBPages is used as the class type for the page list. It is stored in an internal member, and used when TCustomPage class instances for the control are accessed and maintained.

Contains the ordinal position for the active Tab in the control.

TabIndex is an Integer property which contains the ordinal position for the active Tab in the tabbed control. It is the same as the PageIndex property; they read and write the same member value. The default value for the property is -1, and indicates that an active tab (page) has not been selected in the control.

Setting a new value for the property causes the OnChange event handler to be signalled when nboDoChangeOnSetIndex has been included in the Options for the control. The event handler is not signalled at design-time, during LCL component streaming, or when the control is freed.

No actions are performed in the method when the new property value is not in the range -1..PageCount-1, or when the new value is the same as the existing value.

Event handler signalled when the active page (or tab) for the control is changed.

OnChange is a TNotifyEvent property with the event handler signalled when the active page (or tab) for the control is changed. OnChange is enabled when the value nboDoChangeOnSetIndex has been included in the Options for the control.

Setting a new value in either PageIndex or TabIndex signals the assigned and enabled event handler. It is also called from the Change method when selection change messages are handled for the control, and when a tab is re-ordered using the MoveTab method.

Create - constructor for TCustomTabControl: calls inherited Create creates a page list, then sets initial bounds and default values for local variables and properties. TWinControl.Create Owner of the class instance. Destroy - destructor for TCustomTabControl: clears and frees pages and list, then calls inherited Destroy. TWinControl.Destroy TCustomControl.Destroy TComponent.Destroy Gets the client rectangle for the control adjusted to the parent (when needed). Gets the ordinal position for the image displayed on the tab for the specified page.

GetImageIndex is an Integer function used to get the ordinal position in Images for the image displayed on the specified tab. ThePageIndex contains the Page examined in the method to get its ImageIndex property. If Page does not have a TCustomPage instance at the position in ThePageIndex, -1 is used as the image index.

GetImageIndex signals the OnGetImageIndex event handler (when assigned) to allow a custom image index to be used in the return value.

GetImageIndex is called from methods in the widgetset class when the image displayed on a tab is needed.

Ordinal position in Images for the specified page index. Ordinal position in Page with the image index for the tab. IndexOf - returns the index value of a specified page. CustomPage - returns the page specified by Index. CanChangePageIndex - determine whether it is permissible to change the index of the page. GetMinimumTabWidth - find the smallest permissible tab width. GetMinimumTabHeight - find the least permissible height for a tab. GetCapabilities - returns the set of capabilities. Gets the real page index for the specified tab.

TabToPageIndex is an Integer function used to get the page index for the tab at the specified position. The tab index value in AIndex does not include any non-visible tabs. TabToPageIndex adjusts the index value to include any TCustomPage instances in Page with its TabVisible property set to False.

The return value contains the value specified in AIndex after adding any non-visible pages proper to the requested position.

No actions are performed in the method at design-time; all pages are visible on the designer surface.

Maps the LCL page to the tab index in the widgetset class. DoCloseTabClicked - perform the action associated with clicking the Close tab for this page (OnCloseTabClicked). HotTrack - the property whereby the item under the mouse pointer becomes emphasized. Images - the list of images associated with the pages of this notebook. Width for the Images used in the control.

ImagesWidth specifies the width used for the Images in the control. ImagesWidth determines the resolution (either selected or resized) for the current display density (PPI).

Changing the value in the property causes the DoImageListChange method to be called to select the image resolution, and to notify the widgetset class of the change. The UpdateTabProperties method is called to propagate the change to all tabs in the control.

MultiLine - whether the Tab's caption is allowed to have multiple lines. MultiSelect - whether multiple Tabs are allowed to be selected at the same time (e.g. by pressing Shift or Ctrl while selecting). OnChanging - event handler for changing a tab. OnCloseTabClicked - event handler for clicking on the Close button to close a tab. OnGetImageIndex - event handler for getting an image index. The set of Options for the Notebook: Show close buttons on the tabs, multi-line tabs.

The set of Options for the Notebook:

nboShowCloseButtons (display a little Close Button on the Tab next to the label to allow a user to close that tab),

nboMultiLine (allows multi-line captions on the Tabs)

OwnerDraw - is the calling routine (Owner) allowed to specify the drawing method? The current Page of the Notebook. PageCount - the number of Pages in the Notebook. PageIndex - Index number of the current page. The list of page names in the control. RaggedRight - un-justified or un-aligned text. ScrollOpposite - is scrolling to happen in the opposite direction to usual? ShowTabs - if True (default condition), show the tabs for each page. Style - Tabs, buttons or flat buttons? TabHeight - height of the tabs. TabPosition - top, bottom, left or right. Width of the tabs displayed on the control. Enables or disables navigation using the Tab key.

The default value for the property is True in TCustomTabControl.

TWinControl.TabStop An individual page used in TPageControl.

TTabSheet - individual page of a TPageControl. It is a more elaborate version of TPage, and adds the following features:

Drag/Drop properties
Ability to Enable/Disable the page
Ability to make the Tab visible or hidden

Using Multi-Page Controls How To Use Standard Controls Gets the value for the PageControl property. Value for the property. Gets the value for the TabIndex property. Value for the property. Sets the value for the PageControl property. New value for the property. calls inherited Create and zeroes ImageIndex. TComponent.Create Destroy - destructor for TTabSheet: detaches from the Host Dock Site and calls inherited Destroy. TComponent.Destroy The PageControl of which this TabSheet is a member. TabIndex - the Index value or sequence number of this TabSheet. Indicates if the tab is visible in the Parent control.

TabVisible indicates if the Tab is visible in the Parent control. The default value for the property is True in TTabSheet.

When the Parent control has been assigned and has a handle allocated, the TCustomTabControl in Parent is updated to reflect the new value for the property. When True, the active page in the Parent control is changed to the current page instance if one has not already been assigned in the Parent. The page and its handle are removed from the Tab control when the property value is False.

Use IsControlVisible to determine if the page is currently the active page displayed in the Parent tab control.

TCustomPage.TabVisible TPageControl - provides a series of tabs along the edge of a multi-page component to allow selection of one of the pages (TTabSheet) of the component.

TPageControl provides a series of tabs along an edge of a multi-page component to allow selection of one of the pages (TTabSheet) defined for the component.

To use TPageControl, select its icon from the Common Controls tab of the IDE Component Palette and place it at the desired location on the Form.

Use the Form Designer and Object Inspector to adjust its shape, size, alignment, anchoring, docking and other properties, then select the object and right click with the mouse to bring up a pop-up menu whose first item is 'AddPage'. After you have added as many pages as you need, the individual pages can be edited by selecting ActivePage in the Object Inspector choosing the page required and editing its properties.

While a given page is selected, it is also possible to drop other controls (such as buttons, memo boxes etc) on to the page from the Component Palette.

Inherits most of its properties from TCustomTabControl

Using Multi-Page Controls Clears the list of tab names of the control, and causes the associated tab sheets or pages to be freed.

By calling the Clear method of the protected Tabs property in the TCustomTabControl ancestor, this method removes all tab sheets from the PageControl. The TPageControl.PageCount is 0 afterwards.

Note, however, that the controls on the tab sheets are only destroyed when their Owner is one of the tabsheets. Otherwise they still exist on the form, but their Parent has been set to nil.

Gets the value for the ActivePageIndex property. Value for the property. Gets the value for the ActivePage property. Value for the property. Gets the value for the Pages property. Value for the property. Ordinal position for the page or tabsheet requested in the method. Sets the value for the ActivePageIndex property. New value for the property. Sets the value for the ActivePage property. New value for the property. Finds the tabsheet in the Pages property which is the parent for the control specified in Client. Gets the class type used to create a new tabsheet (or page) for the page control. Class type used to create new instances of TPageControl. DoAddDockClient creates a new TabSheet in the PageControl, places the client on it and aligns it. Client cannot be added to TPageControl itself but new TabSheet should be added and client placed onto it. TWinControl.DoAddDockClient Called to check whether this control allows docking and where. DoRemoveDockClient - frees the page which is being undocked. TWinControl.DoRemoveDockClient FindNextPage - returns the next page (TTabSheet) in the sequence. SelectNextPage - checking that its tab is visible.

If GoForward is True, goes to next (higher index) page;

if False, goes to previous (lower index)

If CheckTabVisible is True, will only move if the tab is visible

Convenience routine used to make the TPageControl more intuitive to use. Page class instance created in the method. ActivePageIndex - index value of currently selected (active) page. Pages - the actual Pages (TTabSheet) that comprise the component. ActivePage - the currently selected active page (TTabSheet).

ActivePage - the currently selected active page (TTabSheet).

Please note that the property is implemented with a type that differs from TCustomTabControl, where ActivePage is defined as a String. OnChange - Occurs immediately after a tab is selected. Occurs immediately after a tab is selected. TTabControlStrings - the Strings that appear on the tabs of TTabControl. GetTabIndex - returns the Index value of the current Tab. SetHotTrack - specifies the status of HotTrack. SetImages - specifies the list of images to be used. SetMultiLine - specifies whether multi-line captions are used. SetMultiSelect - specifies whether MultiSelection is available. SetOwnerDraw - specifies whether an owner-derived drawing can be used. SetRaggedRight - specifies whether ragged-right (as opposed to right-justified) alignment is to be used. SetScrollOpposite - specifies whether scroll bars are to operate in the opposite sense to normal. SetTabIndex - specifies an index value for a tab. Create - constructor for TTabControlStrings: calls inherited Create then sets many local defaults.

Create is the constructor for TTabControlStrings. It calls the inherited Create method then sets default values in the class instance.

Among the defaults set are:

HotTrack, Multiline, MultiSelect, OwnerDraw, RaggedRight, ScrollOpposite - all False; Tab height and width to zero

TObject.Create GetHitTestInfoAt - returns the results of a hit test at the specified location X, Y. Gets the size for the String displayed on a tab control. IndexOfTabAt - returns the Index value of the tab at the specified location X, Y. RowCount - number of rows (for a multi-row string). TabRec - returns the coordinates of the rectangle for the tab with specified index. ImageListChange - method for changing the image list. ScrollTabs - scrolls the tabs by an amount specified by Delta. TabControlBoundsChange - method for dealing with a change in the bounds of a Tab Control. UpdateTabImages - bring the tab images up to date. BeginUpdate increments the Update count. TStrings.BeginUpdate EndUpdate decrements the Update count. An exception is raised if the Update count is zero TStrings.EndUpdate IsUpdating - returns True if in the process of updating. The TabControl to which these strings apply. TabIndex - the index of the current Tab. HotTrack - the property whereby the item under the mouse pointer becomes emphasized. TCustomListView.HotTrack The list of Images associated with the Strings for these tabs. MultiLine - if True, multiple lines may be used in Tab strings. MultiSelect - if True, multiple tabs can be selected, for example by holding down Shift or Ctrl keys while selecting. OwnerDraw - if True, Owner object (or calling routine) can specify drawing methods. RaggedRight - if True, strings are un-justified or un-aligned with ragged right margin. ScrollOpposite - if True, scrolling proceeds in opposite direction to usual. Implements the tabbed page control used in TNoteBookStringsTabControl.

TNoteBookStringsTabControl is a TPageControl descendant which implements the tabbed page control used in TNoteBookStringsTabControl.

Adjusts the specified coordinates to the ClientOrigin for the parent.

The adjustment amount is the difference between the ClientOrigin for the control and the ClientOrigin for the Parent of the control. The offset amounts are then applied to the values X and Y.

Called from the DragDrop, DragOver, MouseMove, MouseDown, and MouseUp methods.

Horizontal coordinate adjusted in the method. Vertical coordinate adjusted in the method. Gets the value for the PopupMenu property.

GetPopupMenu is an overridden TPopupMenu function which implements the read access specifier for the PopupMenu property. The return value contains the TPopupMenu instance from the Parent control when it is derived from TTabControl and Options contains the value nboHidePageListPopup. Otherwise, the inherited method in TControl is called to get the popup menu instance for the control.

TPopupMenu TControl.GetPopupMenu TControl.PopupMenu TControl.Parent Value for the property. Class type reference for TNoteBookStringsTabControl TTabControlNoteBookStrings - instance of TTabControlStrings for use with a TNoteBook. Gets the value for the Style property. Value for the Style property. Sets the value for the Style property. New value for the Style property. Gets a new instance of a tab control Get returns the text string found on the indexed page. TStringList Gets the value for the Count property.

GetCount is an overridden method in TTabControlNoteBookStrings used to get the value for the Count property. In TTabControlNoteBookStrings, the property contains the value from the PageCount property in NoteBook.

TStrings.Count Value for the Count property. GetObject returns the indexed object from the paged notebook. TStrings.Objects Gets the value for the TabIndex property. Value for the TabIndex property. Gets the value for the TabPosition property. Value for the TabPosition property. NBChanging - method for dealing with the process for change in a NoteBook. NBGetImageIndex - obtains the Image Index associated with a given Tab Index in the NoteBook. NBPageChanged - Method for dealing with a NoteBook page that has changed. Ensures that the bounds for the Tab control are updated when the handle for the class instance is created.

Implements an internal event handler assigned to the TNoteBookStringsTabControl instance for the class.

Put writes the supplied string to the indexed page of the notebook. TStringList PutObject stores the supplied object at the indexed place in the paged notebook. TStrings.Objects SetImages - if the supplied ImageList is of correct type, stores it in the notebook Images area. Sets the value for the MultiLine property. New value for the MultiLine property. Sets the value for the TabIndex property. New value for the TabIndex property. SetUpdateState - if Updating is True, calls BeginUpdate; otherwise calls EndUpdate. TStrings Create - constructor for TTabControlNoteBookStrings: calls inherited Create then sets some default Actions.

Create - constructor for TTabControlNoteBookStrings: calls inherited Create then sets some default Actions.

Among the actions set are: OnGetImageIndex, OnChanging, OnChange. Notebook is created with a nominated parent.

TObject.Create Destroy - destructor for TTabControlNoteBookStrings: frees NoteBook then calls inherited Destroy. TStrings.Destroy Clear calls the Clear method for the client Notebook. TStrings.Clear Delete calls the Delete method for the client NoteBook. TStrings.Delete Insert calls the Insert method for the client NoteBook. TStrings.Insert Indicates the alignment and orientation for the tabs on the control.

TabPosition is a TTabPosition property which indicates how the Tabs on the control are aligned and oriented. The default value for the property is tpTop, and causes the tabs to align across the top of the client display area. The rise area for the control is also aligned to the top of the control.

Changing the property value causes the widgetset class to be updated.

Drawing style used for the tabs on the control.

Style is a TTabStyle property which controls the drawing style used for the tabs on the control. Read and write access to the property value is re-directed to the Style property in Notebook. The default value for the property is tsTabs, as set in the TCustomTabControl instance in NoteBook.

When a new value is assigned to the property, the TabControlBoundsChange method is called to re-calculate and apply the height and/or width for the tab control.

The tab control where the string values are displayed as the caption for the tabs. TTabControl - a series of Tabs along the edge of a display area; selection of a Tab governs the contents of the DisplayRect.

TTabControl - a series of Tabs along the edge of a display area; selection of a Tab governs the contents of the DisplayRect

Use TTabControl by selecting its icon from the Common Controls tab of the IDE Component Palette and placing it at the desired location on the Form. Use the Form Designer and Object Inspector to adjust its shape, size, alignment, anchoring and other properties. Tabs can be added or removed from the component by selecting it, then right-clicking with the mouse to get a pop-up menu whose first item is 'Add Tab'. Once created, the Tabs can be edited by selecting the Tabs entry in the Object Inspector and selecting the ellipsis (...) which will cause a pop-up String editor to appear. The tabs can be given new captions, moved up and down the list or removed altogether as required.

Each Tab has an Index (starting from 0) and this index can be used to specify an entry from Images for display in the DisplayRect.

Using Multi-Page Controls Adjusts the display rectangle to reserve space for an internal border drawn on the control. Gets the value for the DisplayRect property. Value for the property. Gets the value for the HotTrack property. Value for the property. Gets the value for the MultiLine property. Value for the property. Gets the value for the MultiSelect property. Value for the property. Gets the value for the OwnerDraw property. Value for the property. Gets the value for the RaggedRight property. Value for the property. Gets the value for the ScrollOpposite property. Value for the property. Gets the value for the TabIndex property. Value for the property. Gets a rectangle with the space reserved for the tabs on the control including border space. Gets the value for the TabStop property. Value for the property. Sets the value for the HotTrack property. New value for the property. Sets the value for the Images property. New value for the property. Sets the value for the MultiLine property. New value for the property. Sets the value for the MultiSelect property. New value for the property. Sets the value for the OwnerDraw property. New value for the property. Sets the value for the RaggedRight property. New value for the property. Sets the value for the ScrollOpposite property. New value for the property. Sets the value for the Style property. New value for the property. Sets the Height for tabs displayed on the control.

SetTabHeight is used to set the height for the tabs displayed on the control to the value in AValue. SetTabHeight calls GetCapabilities to determine if the value nbcTabsSizeable is included in the capabilities for the control. No actions are performed in the method when nbcTabsSizeable is not present in the controls capabilities list.

SetTabHeight propogates the new tab height to the Notebook which contains the Tabs in the control.

New height for the tabs displayed on the control. Sets the value for the TabPosition property. New value for the property. Sets the value for the Tabs property. New value for the property. Sets the value for the TabStop property. New value for the property. Sets the value for the TabWidth property. New value for the property. Registers the class type with the widgetset.

WSRegisterClass is an overridden class procedure used to register the widgetset class used to create new instances of the class. WSRegisterClass calls the inherited method, and calls RegisterPropertyToSkip to omit the OnDrawTab property when the component is loaded at run-time. OnDrawTab was used in an older version of the LCL.

Sets the value for the Options property. New value for the property. Not implemented in TTabControl. Page handles are not used.

An empty implementation in TTabControl; there are no pages, so no handle is required.

Indicates whether the tab control can update its Tabs property.

Signals the OnChanging event handler (when assigned) to get the return value for the method. The default return value is True when OnChanging has not been assigned.

True if the Tabs for the control can be modified. Indicates if the control can show the tab at the specified position.

Always returns True in TTabControl.

Always returns True in TTabControl. Ordinal position for the requested tab. Changes the active tab for the control.

Change is an overridden method in TTabControl. It re-implements the method from the ancestor class to signal the OnChange event handler (when assigned) to change the active tab for the control. An internal flag is used to determine if a previous call to OnChange has not been completed. No actions are performed in the method when the flag is set.

Change does not call the inherited method.

Handles the notification when a component is added to or removed from the class instance.

Notification is an overridden method in TTabControl, and calls the inherited method on entry. It ensures that the Images member is set to Nil when the component is removed from the class instance.

Component for the notification. Operation performed for the component. Sets the value for the DragMode property.

SetDragMode is an overridden method in TTabControl used to set the value for the DragMode property. It calls the inherited method on entry, and copies the new property value to the Tabs property.

TControl.SetDragMode TControl.DragMode Sets the value for the TabIndex property. New value for the property. Calls the corresponding method in Tabs.

Calls the corresponding method in Tabs.

Object (TCustomTabControl) for the event. Updates the bounds for the control to the specified values.

DoSetBounds is an overridden method in cv TTabControl. It calls the inherited method in entry to adjust the client rectangle for the control and its control flags. Calls the TabControlBoundsChange method in the Tabs property when it has been assigned.

TWinControl.DoSetBounds New value for the Left property. New value for the Top property. New value for the Width property. New value for the Height property. Gets the default size for new instances of the class.

GetControlClassDefaultSize is an overridden TSize class function used to get the dimensions for a new instance of the TTabControl class. The return value contains the Width (CX) and Height (CY) for the class instance.

The default size in TTabControl is 200 pixels (width) by 150 pixels (height).

TSize instance with the dimensions for the new class instance. Updates the canvas handle and paints the control.

PaintWindow is an overridden method in TTabControl. It ensures that the specified device context matches the Handle for the control canvas. When they differ, the value in DC is temporarily used as the canvas handle. The modified canvas handle is reset prior to exiting from the method.

PaintWindow calls the Paint method to render the control using the theme elements details available for a tab control. PaintWindow is called when a paint message is received and applied in the PaintHandler method.

PaintWindow re-implements the method from the ancestor class, and does not call the inherited method.

TWinControl.PaintWindow Device context for the control canvas. Paints the control to its Canvas using theme services.

Paint is a method used to render the tab control to its canvas. It handles the background and tabs for the control excluding any button decorations. Buttons are handled in a differ component. Paint adjusts the display rectangle in ARect to reserved a single pixel on the edge indicated in the TabPosition property. This avoids drawing a border on the edge where the control is aligned.

Paint uses ThemeServices to get theme elements available for a tab control, and to draw the control to its Canvas using the theme details. A raised 3D frame is drawn around the control. At design-time, the Caption for the control is drawn centered in its display area.

TControl.Caption Adjust the specified display rectangle to use the size in Tabs. Calls the AdjustDisplayRect method. Creates the TTabControlNoteBookStrings instance used in Tabs. TTabControlNoteBookStrings instance created in the method. Constructor for the class instance.

Create is the overridden constructor for the class instance. Create calls the inherited constructor, and sets the default values for the following properties in the class instance:

Tabs
TabStop
BorderWidth

Create calls GetControlClassDefaultSize and sets the initial bounds for the control using SetInitialBounds. Create allocates a TControlCanvas instance that is used in the Canvas property.

Owner of the class instance. Destructor for the class instance.

Destroy is the overridden destructor for the class instance. Destroy ensures that resources allocated in the class instance are freed, including:

Buttons (and the associated toolbar)
Internal ImageChangeLinks

Destroy calls the inherited destructor prior to exiting from the method.

Gets the position for the tab at the specified mouse coordinates.

IndexOfTabAt is an overridden overloaded Integer function used to get the position for the tab at the specified mouse coordinates. The overloaded variants allow the mouse coordinates to be specified as a TPoint instance, or two Integer values.

IndexOfTabAt re-implements the methods from the ancestor class to use the TTabControlNoteBookStrings instance in Tabs. Tabs provides the offset for the control from the value in ClientOrigin. The IndexOfTabAt method in Tabs is called to get the return value for the method.

The return value contains the ordinal position in Tabs where the mouse pointer is located.

Ordinal position for the hovered tab in the Tabs property. Horizontal coordinate for the mouse pointer. Vertical coordinate for the mouse pointer. TPoint instance with the mouse coordinates. Gets a set of hit test results for the specified mouse coordinates. Signals the OnGetImageIndex event handler to get an image for the specified tab index. Gets the ordinal position for the tab with the specified Caption. Gets the rectangle where the tab at the specified position is drawn. Gets the number of rows needed to render the Tabs on the control. Always returns 1 in TTabControl. Scrolls the tabs on the control horizontally by the value specified in Delta. Starts an update process for the control.

No actions are performed in the method if the Tabs property has not been assigned.

Calls the BeginUpdate method in Tabs to start the update process.

Finishes an update process for the control.

No actions are performed in the method if the Tabs property has not been assigned.

Calls the EndUpdate method in Tabs to complete the update process. The Change method is called when there no unfinished updates in Tabs and an internal flag is set to trigger the OnChange event handler.

Indicates if there are unfinished updates for one of the Tabs on the control. Display area for the tab control.

DisplayRect is a read-only TRect property which contains the display area for the page in the tabbed control. It uses the client rectangle for the control as the value for the property. Use TabRect to get the display area for the tab in the tabbed control.

TCustomDrawTarget - enumerated type controlling how a target object is drawn. Draw the entire control. Draw one item (or line in report mode). Draw one subitem (except subitem 0 which is drawn by dtItem). TCustomDrawStage a series of constants to define the drawing stages. TCustomDrawStateFlag - series of flags to define the DrawState.

TCustomDrawStateFlag is an enumerated type with values representing the drawing states available in custom-drawn controls. Values from the enumeration are stored in the TCustomDrawState set type passed as an argument to event handlers in list view and tree view controls, and stored internally in the controls.

Control is drawn using the selected style. Control is drawn using the grayed or unselected style. Control is drawn using the disabled style. Control is drawn using the checked style. Control is drawn using the focused style. Control is drawn using the default style. Control is drawn using the hot tracking style. Control is drawn using the marked (multiselected) style. Control is drawn using the indeterminate state style. TCustomDrawState - set of TCustomDrawStateFlag. . TCustomDrawState determines how a item will be drawn. TCustomDrawResultFlag - enumerated type, a series of flags to signify the result of a drawing process. TCustomDrawResult - set of TCustomDrawResultFlag. . Indicates the sort mechanism used for items in tree view and list view controls.

TSortType is an enumerated type with values indicating the sort mechanism used for items in tree view or list view controls. TSortType is the type used to implement the SortType property in both TCustomTreeView and TCustomListView.

Sorting is not used for list items. List items are sorted by their data and not their display text. List items are sorted by their display text and not their data. List items are sorted using both display text and data. Represents state values for items in a list view control.

TListItemState is an enumerated type with values which represent the state for items in a list view control. The values reflect the current settings for properties in TListItem.

Values from TListItemState are stored in the TListItemStates set type.

The list item has its Cut property set to True. The list item has its DropTarget property set to True. The list item has its Focused property set to True. The list item has its Selected property set to True. Set type used to store value(s) from the TListItemState enumeration.

TListItemStates is a set type used to store zero or more values from the TListItemState enumeration. TListItemStates is the type used to implement the States member in TListItem. Values are included in and excluded from the set when the corresponding properties in TListItem are changed.

TListItemFlag - enumerated type, a flag denoting a list item is being destroyed or created. List item has been marked for destruction by a notify message. List item has been marked as created by a notify message. Set type used to store TListItemFlag enumeration values.

TListItemFlags is a set type used to store zero or more values from the TListItemFlag enumeration. It is the type used to implement the internal Flags member in TListItem.

TDisplayCode - enumerated type denoting how items are displayed.

TDisplayCode is an enumerated type with values that denote how the item or subitem is displayed in a list view control. The values are passed as arguments to the DisplayRect and DisplayRectSubItem methods in TListItem, and allows the widgetset to layout and rendering the list items for the platform.

List item is rendered using the Bounds for the item display rectangle. List item is rendered using the width and height for the associated image. List item is rendered using the text metrics for the caption in the item. List item is rendered using the selection rectangle for the item. Represents icon arrangement options in a list view control.

TIconArrangement is an enumerated type with values representing the icon arrangement options for a list view control.

Icons are arranged from the top to the bottom, then left to right in the control. Icons are arranged from left to right, then top to bottom in the control. Contains text wrapping and icon layout settings for a list view control.

TIconOptions is a TPersistent descendant which represents the text wrapping and icon layout settings in the IconOptions property in TCustomListView.

Gets the value for the AutoArrange property. Value for the property. Gets the value for the WrapText property. Value for the property. Sets the value for the Arrangement property. New value for the property. Sets the value for the AutoArrange property. New value for the property. Sets the value for the WrapText property. New value for the property. Assign values from the class instance to the specified persistent object.

AssignTo is an overridden method which implements support for the TIconOptions type in the RTL object persistence mechanism. AssignTo allows property values from the current class instance to the stored to the persistent object in Dest.

When Dest is a TIconOptions instance, AssignTo copies the values from the current class instance:

Arrangement
AutoArrange
WrapText

If ADest is not derived from TIconOptions, the inherited method is called.

TPersistent.Assign Persistent object where property values are stored. Gets the owner of the class instance.

GetOwner is an overridden method in TIconOptions used to get the owner of the class instance. It returns the TCustomListView instance passed as an argument to the Create constructor.

TPersistent Owner of the class instance. Constructor for the class instance.

Create is the overridden constructor for the class instance, and calls the inherited constructor on entry. Create stores the value in AOwner to an internal member used in the class instance, and sets the default value for the Arrangement property to iaTop.

Owner of the class instance. Indicates the icon position relative to the caption in a list item.

Arrangement is a TIconArrangement property which indicates the layout for the icon or image in a list item relative to its caption text. The default value for the property is iaTop, and causes the icon to be displayed above the caption for the list item.

See TIconArrangement for other values in the enumeration and their usage.

Indicates whether icons in a list view can be automatically arranged.

AutoArrange is a Boolean property which indicates if icons in a list view control can be automatically arranged when items are added to the control. The default value for the property is False.

AutoArrange is used when the list view uses the vsIcon or vsSmallIcon view styles.

Indicates if the caption for a list item can wrap into multiple lines.

WrapText is a Boolean property which indicates if the Caption for a list view item can be wrapped into multiple lines. The default value for the property is True.

The Caption for the item is wrapped when its length exceeds the width for the icon in the list item.

Represents the items created in TCustomListView and descendants.

TListItem is the base class for the Items created in TCustomListView and TListView.

TListItem provides properties which identify the content for the list item, like: Caption, SubItems, Data, Index, ImageIndeex, and StateIndex. Other properties indicate the disposition of the item in the control, like: Checked, Cut, DropTarget, Focused, and Selected.

Methods are provided that allow the list item to interact with the control and the widgetset class.

TListItem is the type used in the TListItems container.

TPersistent TObject Gets the value for the Caption property. Value for the property. Gets the value for the Check property. Value for the property. Gets the value for the Left property. Value for the property. Gets the value for the ListView property. Value for the property. Gets the value for the Position property. Value for the property. Gets the value for a state property in the list item. Value for the property. TListItemState enumeration value which identifies the property value returned from the method. Gets the value for the ImageIndex property. Value for the property. Gets the value for the Index property. Value for the property. Gets the value for the StateIndex property. Value for the property. Gets the value for the indexed SubItemImages property. Value for the indexed property. Ordinal position for the sub-item image in the property value. Gets the value for the SubItems property. Value for the property. Gets the value for the Top property. Value for the property. Sets the value for the Checked property. New value for the property. Sets the value for the property identified by the AState argument. TListItemState value which identifies the property updated. New value for the property. Sets the value for the Data property. New value for the property. Sets the value for the ImageIndex property. New value for the property. Sets the value for the Left property. New value for the property. Sets the value for the Caption property. New value for the property. Sets the value for the Position property. New value for the property. Sets the value for the StateIndex property. New value for the property. Sets the value for the indexed SubItemImages property. Ordinal position for the new value. New value for the indexed property. Sets the value for the SubItems property. New value for the property. Sets the value for the Top property. New value for the property. Determines if the specified list item has the same values as the current class instance.

IsEqual is a Boolean function used to determine if the list item has the same values as the list item specified in AItem. IsEqual compares the values in the Caption, Data, and the internal FStates member in both TListItem instances. The return value is True when the content in the instances is the same.

True when the list items have the same content. List item compared to the current class instance. Determines if the list item has an owner with a valid handle.

IsOwnerData is a Boolean function used to determine if the list item has an owner with a valid handle. IsOwnerData always returns False in TListItem. It is overridden in descendent classes like TOwnerDataListItem.

True if the list item has an owner with a valid handle. True if the member variable for the Checked property contains True.

Used in methods in the widgetset class.

Gets the owner of the class instance.

Returns the value in the Owner property.

TPersistent Owner of the class instance. Copies values from the specified persistent object into the current class instance.

Assign is an overridden method used copy property values from the persistent object in ASource into the current class instance. When ASource is a TListItem descendant, the following property values are copied:

Caption
Data
ImageIndex
SubItems

If ASource is not descended from TListItem, the inherited method is called to handle the assignment.

TPersistent.Assign Persistent object with values copied in the method. Constructor for the class instance.

Create is the constructor for the class instance, and calls the inherited constructor on entry. AOwner is the TListItems instance which acts as the container for the list item.

Create sets the default values in member variables used in the class instance. The property interfaces are not used before they are not available until the list item is added to the TListItems container.

TObject.Create Container which owns the list item. Destructor for the class instance.

Destroy is the overridden destructor for the class instance.

Destroy sets the internal flag that marks the list item for destruction in the Owner. When the Owner is assigned, its ItemDestroying method is called to signal destruction of the list item in the container.

Destroy free and Nils resources allocated for the SubItems property, and calls the inherited destructor prior to exit.

TPersistent.Destroy Removes the list item from the container. Makes the item visible in the list view control which owns the container and the list item. True is the list item can be partially visible in the control. DisplayRect - returns the coordinates of a rectangle for displaying the current item.

DisplayRect - returns the coordinates of a rectangle for displaying the current item.

Display codes can be: drBounds, drIcon, drLabel, drSelectBounds.

DisplayRectSubItem - returns the coordinates of a display rectangle for a specified sub-item.

Display codes can be: drBounds, drIcon, drLabel, drSelectBounds.

Makes the item the selection in the list view control and displays the editor when allowed. True if the control is not ReadOnly and the editor is valid, otherwise False. Returns all the states for the list item.

GetStates is a TListItemStates function used to get the state values for an item in a list view control. The state values are retrieved using methods in the widgetset class for the TCustomListView control which owns the list item. If the widgetset class does not return the values, the return value contains the existing values in the States member for the TListItem instance.

State values for the list item. Caption - the name given to this item on the list. Checked - if True, a check mark is present beside the item implying it has been selected. Cut this item from the list (but it can be placed on the clipboard). Pointer to the Data associated with this item. DropTarget - returns True if this is a valid target on the list for dropping. Property is true if this item has Focus. The index of this item in the list (integer). The index of the image associated with this Item in the list. The position of the Left side of the list item. The ListView in which this Item is found. The Owner of the ListItem. The coordinates of the position where the ListItem is located. Whether this Item has been Selected (often denoted by a check-mark).

Selected is a Boolean property which indicates if the list item has been selected. The property value is determined by examining the internal TListItemStates set for the class instance. When lisSelected has been included in the state values, the property is True. Otherwise, the property is False.

Setting a new value for the property causes the value lisSelected to be included in or removed from the internal set. AIsSet indicates whether the state value is set. When True, the state value is included in the set. Otherwise, the state value is excluded.

Ordinal position for the image used to represent the state for the list item. The list of SubItems associated with this ListItem. SubItemImages - the list of Images associated with the SubItems. The position of the Top of this ListItem. Class reference used to create new instances of TListItem. List item used in a list view control when owner data (virtual) mode is enabled.

TOwnerDataListItem is a TListItem descendant which implements a list item used for a list view control in virtual mode.

True if the owner for the list item has been assigned and can be updated in the widgetset class. Sets the internal index position for the virutal item. Sets the TListItems container which owns the list item. Implements an enumerator for TListItem values in a TListItems container. Constructor for the class instance. List items navigated in the enumerator. Moves to the next value for the enumerator. Current value for the enumerator. Widgetset flags applied to the TListItems container. Set type used to store TListItemsFlag enumeration values. TListItems - a list of items with a cache of the last accessed item. TListitems has a built-in cache for the last accessed item. This will speed up interface updates since Item.Index is often used for the same item updating more properties. If FCacheIndex contains -1 then the cache is not valid. Reads data in a Delphi compatible way. Reads data in a 64-bit safe way. Writes data in a 64-bit safe way. DefineProperties - calls inherited method, then defines some specific binary properties. TPersistent GetCount - find the number of Items in the list. GetItem returns the ListItem specified by AIndex. . Gets the owner of the persistent object. TCustomListView instance that owns the list items. WSCreateItems - instruction to the widgetset to create Items. Updates flags in the class instance when the widgetset handle is freed. Sets the value for the Count property. New value for the Count property. SetItem - writes the Index and content of a given Item to a local variable. Clears the selected state for all TListItem instances in the class. Sets the selected state for all TListItem instances in the class. Add an Item to the Collection. AddItem - add the specified AItem to the collection. BeginUpdate - start the update process. Clear - remove all Items from the list. Create - constructor for TListItems: calls inherited Create then creates the list. TObject.Create Destroy destructor for TListItems: frees the individual items on the list, then calls inherited Destroy. . TPersistent.Destroy Remove the Item specified by AIndex from the collection. EndUpdate - finish the update process. Exchanges the list items stored at the specified positions. Moves the list item at the specified position to a new position in the list. FindCaption - returns the ListItem with the specified caption at the given starting place. FindData - returns the ListItem associated with the specified data pointer. Gets an enumerator for the Item values in the list. Gets the ordinal position in the list for the specified list item. Insert an item in the list at AIndex, returning the value of the ListItem. InsertItem - procedure to insert AItem at position AIndex in the list. Contains the flag values currently assigned to the list.

Flags is a read-only TListItemsFlags property with the flag values currently assigned to the list. Values in flags are added and removed as needed in methods for the class instance.

Count - the number of items in the collection. An Item in the list, specified by its Index value. Owner - the ListView that owns this collection of ListItems. Faux container for the items in a list view control when owner data (virtual) mode is enabled.

Only the most recent list item is actually populated in the list view control when owner data is enabled.

Gets the value for the Count property. Value for the Count property. Sets the value for the Count property. New value for the Count property. Gets the value for the indexed Item property. Value for the property. Ordinal position for the indexed property value. Frees the list items stored in the Items property. ImageIndex. TWidth is an Integer range type. Range is 0..MaxInt. Represents the sort indicators available for a column in a list view control.

TSortIndicator is an enumerated type with values that represent the sort indicators available in the TListColumn class. TSortIndicator is the type used to implement the SortIndicator property in TListColumn.

No sort indicator is used for the list column. Uses an ascending sort indicator for the list column. Uses a descending sort indicator for the list column. Represents an individual column in a multi-column list control.

TListColumn is a TCollectionItem descendant which represents an individual column in a multi-column list control.

TListColumn is the type used for items added to the TListColumns collection, and maintained in the TCustomListView.Columns property.

TCollectionItem Sets the value for the Index property.

Calls the inherited method to move the collection item to the position indicated in the property value. Calls the ColumnMove method in the widgetset class to reorder the column in the control.

TCollectionItem.Index New value for the Index property. Gets the value for the DisplayName property.

GetDisplayName returns the Caption for the control, and when blank, calls the inherited method to the property value.

TCollectionItem.DisplayName Value for the DisplayName property. Gets the value for Width as included in LCL component streaming. Returns the value in the Width property. Constructor for the class instance.

Create is the constructor for TListColumn, and sets the default values for properties, including:

Alignment
Caption
Width
Visible
MinWidth
MaxWidth
AutoSize
Tag
ImageIndex

Create calls the inherited Create method to instantiate the class instance and assign the value in ACollection as the owner for the class instance.

TCollectionItem.Create Destructor for the class instance.

Destroy is the destructor for TListColumn. When the collection allows updates, the update is suppressed for the column instance that is being destroyed. Calls the inherited method to clear the owner for the collection item and destroy the class instance. The columnDelete method in the widgetset class is called to remove the column.

TCollectionItem.Destroy Copies properties from the specified persistent object to the current class instance.

Assign is an overridden method used to implement object persistence for the TListColumn type. It copies property values from the persistent object in ASource into the current class instance. When ASource is derived from TListColumn, the following properties are copied:

Alignment
AutoSize
Caption
MaxWidth
MinWidth
Visible
Width

The Changed method is called to signal a change in the values for the collection item.

If ASource is not derived from TListColumn, the inherited method is called using ASource as an argument. An EConvertError exception is raised if ASource has not been assigned (contains Nil).

TPersistent.Assign Not used in LCL.

WidthType is a read-only TWidth property. Provided for VCL code compatibility.

Sets the horizontal alignment for the Caption text.

Left or right justified, or centered.

When other columns have fixed width, auto-calculate width of this column, to fill entire width. Caption text for the column. Index of icon, inside ImageList object for columns of Listview. Maximal width for this column. Minimal width for this column. Int value, to store some info for this column. Allow to show this column. Current width of column. May be calculated auto, if AutoSize used. Sort indicator for the column. Reflects the sort direction for the list view control where the column is used. TListColumns - a collection of Items of type TListColumn (the columns appearing in a multi-column list). Gets the owner of the persistent object. TPersistent object instance that owns the collection. Create - constructor for TListColumns: sets ownership then calls inherited Create. TCollection.Create Destroy - destructor for TListColumns: calls inherited destructor. TCollection.Destroy Update checks if update is in fact required, then calls inherited method. TCollection Add calls inherited method, then adjusts state flags. TCollection.Add Owner of the collection instance.

Owner is a read-only TCustomListView property which contains the control that is the owner of the column collection. Its value is set to the argument passed to the Create constructor.

Provides indexed access to the items in the column collection.

Items is the default property for the collection, and the target for an enumerator used with the class instance.

TCollection.Items Ordinal position for the indexed property value. Assign checks that source is of correct type, then adds new columns and copies items from source into them; otherwise calls inherited Assign which probably raises an exception. TCollection.Assign TItemChange - enumerated type for kind of change: in text, in image or in state. Represents the view styles available for the items in a list view control.

TViewStyle is an enumerated type with values representing the view styles available for the items in a List View control. TViewStyle is the type used for the ViewStyle property in TCustomListView.

Displays a large icon and the caption for each list view item. The icon is centered above the caption text. Displays a small icon and caption text for each list view item. Caption text on the right-hand side of the icon. Displays a small icon with caption text to its right-hand side. The list items are arranged in columns. Displays a each list item as a series of columns with a small icon on the left-hand side of the row. Each columns has a header at the top of the list view control. Represents a search mechanism used to locate the data for a list view item.

TItemFind is the type passed as an argument to TLVDataFindEvent and used to implement the OnDataFind event handler in TCustomListView.

Not used in the current implementation. Not used in the current implementation. Not used in the current implementation. Not used in the current implementation. Represents search direction used to locate the list view item nearest to given coordinates.

Values from TSearchDirection are passed as an argument to the GetNearestItem method in TCustomListView.

Searches to the left of the specified list view coordinates. Searches to the right of the specified list view coordinates. Searches above the specified list view coordinates. Searches below the specified list view coordinates. Searches in all directions for the list view closest to the given coordinates. Event handler signalled when a property value for a list view item is changed.

TLVChangeEvent is an object procedure which specifies an event handler signalled when a property value for a list view item is changed. Arguments passed to the method identify the list view control, the list view item, and the specific property for the event notification.

TLVChangeEvent is the type used for the OnChange property in TCustomListView.

Object instance (TCustomListView) for the notification. List item for the notification. Indicates the property value that was changed in Item. Not used in the current LCL implementation. Not used in the current LCL implementation. Not used in the current LCL implementation. TLVColumnClickEvent - generic event handler method for a click on a List View column. TLVColumnRClickEvent - generic event handler method for a right click on a List View column. Specifies a routine used to compare the values in two items in a list view control.

TLVCompare is a routine used to determine the relative sort order for the list items passed in the Item1 and Item2, and allows an optional Integer parameter value used in the comparison. The return value is the relative sort order for the TListItem instances. For example:

-1: Item1 comes before Item2 in the sort order.
0: Item1 and Item2 have the same sort order value.
1: Item1 comes after Item2 in the sort order.

A TLVCompare type is passed as an argument to the CustomSort method in TCustomListView.

Relative sort order for the specified list items. First list item for the comparison. Second list item for the comparison. Pointer to an optional Integer value used in the comparison. TLVCompareEvent - generic event handler method for List View comparison. TLVDeletedEvent - generic event handler method for deleted items in List View. Specifies an event handler signalled when an edit action is started for an item in a list view control. Specifies an event handler signalled when an edit action is completed for an item in a list view control. TLVInsertEvent - generic event handler method for List View insertion. Alias to the TLVDeletedEvent type. Specifies an event handler signalled when the checked state for an item in a list view control has been changed. TLVSelectItemEvent - generic event handler method for List View selection. TLVCustomDrawEvent - generic event handler method for List View custom drawing. TLVCustomDrawItemEvent - generic event handling method for List View item drawing. TLVCustomDrawSubItemEvent - generic event handling method for List View subitem drawing. Specifies an event handler signalled to draw an item in a list view control. TLVAdvancedCustomDrawEvent - generic event handling method for List View custom drawing. Specifies an event handler signalled to perform advanced custom drawing for a list view item with stage and state information. TLVAdvancedCustomDrawSubItemEvent - generic event handling method for List View custom subitem drawing. Specifies an event handler signalled to get the class type needed to create a new list view item.

Arguments to the object procedure identify the list view control (Sender) and the class type (ItemClass) used to create new list view items. ItemClass is a variable parameter which is updated in the event handler with the TListItemClass class reference needed for the list view control.

TLVCreateItemClassEvent is the type used for the OnCreateItemClass property in TCustomListView.

Object (TCustomListView) for the event notification. Class for the new list view item. Represents Boolean properties used in TCustomListView.

TListViewProperty is an enumerated type with values representing Boolean properties used in TCustomListView.

Values from the enumeration are included in or excluded from the TListViewProperties set type. When a value is included in the set, the corresponding Boolean property has been set to True. When a value is excluded from the set, the corresponding Boolean property has been set to False.

Represents the AutoArrange property in TCustomListView. Represents the CheckBoxes property in TCustomListView. Represents the ColumnClick property in TCustomListView. Represents the FlatScrollBars property in TCustomListView. Represents the FullDrag property in TCustomListView. Represents the GridLines property in TCustomListView. Represents the HideSelection property in TCustomListView. Represents the HotTrack property in TCustomListView. Represents the MultiSelect property in TCustomListView. Represents the OwnerDraw property in TCustomListView. Represents the ReadOnly property in TCustomListView. Represents the RowSelect property in TCustomListView. Represents the ShowColumnHeaders property in TCustomListView. Represents the ShowWorkAreas property in TCustomListView. Represents the WrapText property in TCustomListView. Represents the ToolTips property in TCustomListView. Set type used to store values from the TListViewProperty enumeration.

TListViewProperties is a set type used to store zero or more values from the TListViewProperty enumeration.

The set represents Boolean property values found in TCustomListView / TListView. When a value is included in the set, the corresponding property in TCustomListView has been set to True. The value is excluded from the set when the corresponding property in TCustomListView is set to False.

TListViewProperties is the type used to implement the internal FProperties member in TCustomListView.

Represents the image list sizes used in TCustomListView.

TListViewImageList is an enumeration type with values that represent image list sizes used in TCustomListView.

Represents the SmallImages property in TCustomListView. Represents the LargeImages property in TCustomListView. Represents the StateImages property in TCustomListView. Represents cursor shapes displayed during hot tracking in a control.

TListHotTrackStyle is an enumerated type with values for cursor shapes displayed for the "hot tracking" state in a TCustomListView control. Hot tracking occurs when the mouse pointer hovers over an item in a control, and it is highlighted (aka hot-lighted). Values from TListHotTrackStyle are stored in the TListHotTrackStyles set type used for the TCustomListView.HotTrackStyles property.

For current ListView item, show the HandPoint mouse cursor. For current ListView item, show the pale underline. For current ListView item, show the bold underline. Set type used to store values from TListHotTrackStyle.

TListHotTrackStyles is a set type used to store zero or more values from the TListHotTrackStyle enumeration. TListHotTrackStyles is the type used to implement the TCustomListView.HotTrackStyles property.

Represents flag values used in TCustomListView when sorting or validating items in the control. The value in the Selected property is valid. Items in the control are being moved. Items in the control are being sorted. Sort parameters are being prepared. Set type used to store values from the TListViewFlag enumeration.

TListViewFlags is the type used to implement the internal flags for the TCustomListView control.

Represents the sort directions used for items in a list view control. Sorts list items in ascending order. Sorts list items in descending order. Provides multi-platform editing capabilities for a list view control.

Used to provide multi-platform editing capabilities for TCustomListView. It implements the internal editor control in TCustomListView.

Implements the OnKeyDown event handler for the editor control.

Ensures that the VK_ESCAPE and VK_RETURN virtual key codes are handled for the editor. VK_ESCAPE causes the editor to be hidden, and focused is returned to the parent control. VK_RETURN does not hide the editor, but focus is returned to the parent control. In both cases, Key is set to 0 to indicate that the key was handled in the method.

TWinControl.OnKeyDown Object for the event notification. Virtual key code examined in the method. Shift / Ctrl / Alt modifier for the key code. Performs actions needed when the editor loses focus.

Calls the HideEditor method in the parent control (TCustomListView). Calls the inherited method prior to exit.

Constructor for the class instance. Create is the overridden constructor for the class instance, and calls the inherited method on entry. List item updated in the editor control.

Item is a TListItem property with the list item updated in the editor control. The value in Item is assigned in the ShowEditor method in the parent control (TCustomListView). Item is set to Nil when the editor control is hidden.

TCustomListView is the base class for TListView.

TCustomListView is the base class for TListView. It provides a multi-platform implementation of the List View control from the Windows API. TCustomListView allows a collection of items to be displayed using different view styles. For instance:

Icon View: Each list item has an large icon with a caption.
Small Icon View: Each list item has a small icon with a caption.
List View: Each list item has a small icon with a caption, and is displayed in a single column in the control.
Report View: Each list item is displayed on a single line, with sub-items displayed as additional columns. The first column has a small icon and a caption. Other columns contain the text for the sub-items.

TCustomListView does not implement some features available for Windows version 6 or higher, including: the Tile View style, List View Item Grouping, and List View Work Areas.

	Source Property (in TMenuItem)	Target Property (in TToolButton)
Action	Action
Caption	Caption
Checked	Down
Enabled	Enabled
Enabled	Enabled
Hint	Hint
ImageIndex	ImageIndex
Visible	Visible