- TCustom Notebook: The base type for TNotebook and TPageControl + TCustom Notebook: The base type for + TNotebook and + TPageControl
A notebook consists of several Pages, usually of similar type and kept indexed. They may contain Images listed in a table. One page is displayed at a time, but the other pages are indicated by tabs which may have their names on them, and a different page can be selected for display by clicking its tab
The set of Options for the Notebook:
++ nboShowCloseButtons (display a little CloseButton on the Tab next to the label, to allow the user to close that tab),
++ nboMultiLine (allows multi-line captions on the Tabs)
+- TNotebook: A series of tabbed pages placed together to make a notebook
+ TNotebook: A series of tabbed + + pages placed together to make a notebookA notebook consists of several Pages, usually of similar type and kept indexed. They may contain Images listed in a table. One page is displayed at a time, but the other pages are indicated by tabs which may have their names on them, and a different page can be selected by clicking its tab
Inherits most of its properties from TCustomNoteBook
+To use a Notebook, select its icon from the 'Additional' tab of the Component Palette and place it on the Form. Adjust its size, position, alignment and anchoring as required, by moving the object on the Form or by using the Object Inspector.
+Tabbed Pages are added to the NoteBook by selecting the control and right-clicking with the mouse to get a pop-up menu whose first item is 'Add Page'. Pages already in the NoteBook can be edited by selecting the appropriate ActivePage in the Object Inspector and modifying its properties or adding additional components to that Page.
Set of Options for this Notebook. Include nboShowCloseButtons, nboMultiLine +
+To use the Options, select the tag in the Object Inspector, then select for inclusion any of the listed options, setting them True or False as appropriate.
+For example, setting nboShowCloseButtons to True will cause a CloseButton (a small CheckBox with an 'x' in it) to appear on each Tab of the NoteBook, allowing the tabbed Page to be closed when the user clicks on the CloseButton.
+- TShape: An arbitrary graphic geometrical shape placed on the Form. It may be one of a series of standard shapes defined by TShapeType (stRectangle, stSquare, stRoundRect, stRoundSquare, stEllipse, stCircle, stSquaredDiamond, stDiamond).
+ TShape: An arbitrary graphic geometrical shape placed on the Form. It may be one of a series of standard shapes defined by + TShapeType (stRectangle, stSquare, stRoundRect, stRoundSquare, stEllipse, stCircle, stSquaredDiamond, stDiamond).It can be displayed using the Paint method and the Brush and Pen tools.
Which Shape?
+stRectangle,
+stSquare,
+stRoundRect,
+stRoundSquare,
+stEllipse,
+stCircle,
+stSquaredDiamond,
+stDiamond
+TCustomSplitter: the base type for + TSplitter
A Splitter is a vertical or horizontal bar that can be placed on a panel or form, to separate sub-panels functionally and allow re-sizing of the constituent sub-panels
@@ -2718,6 +2759,7 @@TCustomRadioGroup: the base type for + TRadioGroup
A group of related but mutually exclusive radio buttons, @@ -3607,12 +3653,14 @@ requiring the user to select one af a set of alternatives
TRadioGroup behaves differently from a group of + TRadioButton controls placed arbitrarily around a form.
In the case of TRadioButton, the mutual exclusivity is a feature that applies to any RadioButton anywhere in the Form, and the RadioButtons can be rearranged in any order or placed anywhere within the containing Form, while in TRadioGroup the exclusivity applies only to buttons within the Group, which are ordered strictly according to their ItemIndex within the Items stringlist.
TRadioButton is an entity in itself, with a number of additional properties, whereas the buttons within + TRadioGroup are not separate entities, but rather are simply entries in a list of strings, each of which is associated with the on-screen image of a + RadioButton.
The example shows the difference between the use of TRadioButton and TRadioGroup
@@ -3901,11 +3952,13 @@ requiring the user to select one af a set of alternativesTCustomCheckGroup: The base type for + TCheckGroup
This class defines Items, where the captions for individual check boxes are stored, Rows and Columns for arranging the check boxes, and ColumnLayout to determine whether the data are arranged down the columns first, or across the rows first.
@@ -4193,12 +4246,14 @@ requiring the user to select one af a set of alternativesNote particularly the EditLabel property (see TBoundLabel), which contains the label attached to the Edit control.
TCustomPanel: The base type for + TPanel
A Panel is a defined rectangular area of the form into which other components can be placed to group them functionally and geographically.
@@ -5531,6 +5591,7 @@ either right-click on the control to see the pop-up CheckGroup editor, or in theAssign copies the contents of + Source to + Self, if the classes of the destination and source classes are compatible.
@@ -5739,18 +5808,38 @@ will copy the contents of the Source class to theMulti-PageControls - controls that offer a selection of alternative pages for display
-A number of controls, found in Units ExtCtrls and ComCtrls, offer the ability to create multi-page forms with a series of Tabs along one edge that allow the user to select one of the
Pages
for display and interaction. +A number of controls, found in Units ExtCtrls and ComCtrls, offer the ability to create multi-page forms with a series of Tabs along one edge that allow the user to select one of the Pages for display and interaction.
These include: TPageControl, TNoteBook, TTabControl and THeaderControl (the Header Control components have a very different structure and function). Icons for all of these exist on the Additional or Common Controls tabs of the Component Palette in the Lazarus IDE.
While the various components may look superficially similar, they differ in properties, inheritance, method of adding additional pages, behaviour at run-time, methods for referencing pages and so on.
-We have to be very clear when using the various properties, to distinguish between the word 'Tab' as referring to a Tab indicating an identifier for a page, and 'Tab' as referring to the TAB key on the standard keyboard. In common with most Lazarus components, it is possible to enable each control to be inclused in the TabOrder of TabStops for a Form, so that the component can be reached by repeated pressing of the TAB key, and we must not confuse this use of 'Tab' with the use to denote a Page.
+We have to be very clear when using the various properties, to distinguish between the word 'Tab' as referring to a Tab indicating an identifier for a page, and 'Tab' as referring to the TAB key on the standard keyboard. In common with most Lazarus components, it is possible to enable each control to be included in the TabOrder of TabStops for a Form, so that the component can be reached by repeated pressing of the TAB key, and we must not confuse this use of 'Tab' with the use to denote a Page.
The properties CanTab, TabStop and TabOrder refer to the use of the TAB key to navigate to the relevant control.
Properties such as Tabs, TabIndex, IndexOfTabAt(), TabIndexAtClientPos(), TabPosition, TabHeight, TabWidth, TabVisible, OnCloseTabClicked refer to the use for Page selection.
TNoteBook and + + + + TPageControl are both descended from + + + + TCustomNoteBook (which is in turn descended from + + + + TWinControl) and have many inherited properties in common. + + + + TPageControl has, in general, more advanced features and is probably intended to replace + + + + TNoteBook.
The following table summarises the main differences between the two components.
| Pages, ActivePage | -String, TPage | -TTabSheet, a more advanced version of TPAge | +String, TPage + | ++ TTabSheet, a more advanced version of + + + TPage + |
| Drag/Drop/Dock | @@ -5775,28 +5870,63 @@ will copy the contents of the Source class to the||||
| Indexing | -PageIndex | -ActivePageIndex, TabIndex | ++ PageIndex + | ++ ActivePageIndex, + + + TabIndex + |
| Showing/Hiding Tabs | -ShowTabs | -TabVisible in TTabSheet | ++ ShowTabs + | ++ TabVisible in + + + TTabSheet + |
| Hints | No Hinting methods | -ShowHint, ParentShowHint | ++ ShowHint, + + + ParentShowHint + | |
| Font | No Font properties | -Font, ParentFont | ++ Font, + + + ParentFont + | |
| Sensing position of Tab | None | -TabPosition, OnGetSiteInfo | ++ TabPosition, + + + OnGetSiteInfo + | +|
| Options | +Published property Options, include nboShowCloseButtons, nboMultiLine + | +No published Options property, but inherits Options (public property) from TCustomNoteBook, so they could be set explicitly in code |
The individual Pages in both of the above controls (descended from TCustomNoteBook) are separate and can have their own specific collections of widgets which appear only when the relevant Page is selected by its Tab.
@@ -5808,8 +5938,13 @@ will copy the contents of the Source class to theThe pages inTNoteBook or TPageControl can be edited by selecting the ActivePage in the Object Inspector and then editing the properties of the individual page.
THeaderControl offers a widget that could be placed along the edge of a Panel or Form, allowing a highly customised mechanism for selection. However, there are no intrinsically associated display areas, and it is the developer's responsibility to supply an index associated with the selection from the + + + + THeaderControl and determining what action is to occur or what is to be displayed in any attached Panel or Form.
-When the control is first placed selected from the Component Palette and placed on a Form, it consists of an unadorned rectangle. However, selecting the control and right-clicking (or selecting the 'Sections' property in the Object Inspector) gives access to a Sections editor (a StringList editor) and Sections can be added to the control. The sections are separated by vertical lines, and each section can have a string inserted as a label, associated with an Index value. The Sections can be rearranged, re-ordered, or be individually painted
+When the control is first selected from the Component Palette and placed on a Form, it consists of an unadorned rectangle. However, selecting the control and right-clicking (or selecting the 'Sections' property in the Object Inspector) gives access to a Sections editor (a StringList editor) and Sections can be added to the control. The sections are separated by vertical lines, and each section can have a string inserted as a label, associated with an Index value. The Sections can be rearranged, re-ordered, or be individually painted.
+In a typical application a THeaderControl and a TPanel or TForm would be docked together, and code would be written to find which Section of the Header had been selected, then use its index to control the display in the other docked control.