lazarus/lcl/dbctrls.pp

1967 lines
61 KiB
ObjectPascal

{ $Id$}
{
/***************************************************************************
DbCtrls.pp
----------
An interface to DB aware Controls
Initial Revision : Sun Sep 14 2003
***************************************************************************/
*****************************************************************************
This file is part of the Lazarus Component Library (LCL)
See the file COPYING.modifiedLGPL.txt, included in this distribution,
for details about the license.
*****************************************************************************
}
{
@abstract(common db aware controls, as in Delphi)
@author(Andrew Johnson <acjgenius@@earthlink.net>)
@created(Sun Sep 14 2003)
@lastmod($Date$)
}
unit DBCtrls;
{$mode objfpc}
{$H+}
interface
uses
Types, Classes, SysUtils, DB, Variants,
// LCL
LCLStrConsts, LMessages, LCLType, LCLIntf, LResources, Controls, Graphics,
Dialogs, StdCtrls, Buttons, MaskEdit, ExtCtrls, Calendar, ImgList,
// LazUtils
GraphType, LazTracer, LazUtilities;
Type
{ TFieldDataLink }
TFieldDataLink = class(TDataLink)
private
FField: TField;
FFieldName: string;
FControl: TComponent;
// Callbacks
FOnDataChange: TNotifyEvent;
FOnEditingChange: TNotifyEvent;
FOnUpdateData: TNotifyEvent;
FOnActiveChange: TNotifyEvent;
// Curent State of Affairs
FEditing: Boolean;
FEditingSourceSet: boolean;
FEditingSource: Boolean;
IsModified: Boolean;
function FieldCanModify: boolean;
function IsKeyField(aField: TField): Boolean;
function GetCanModify: Boolean;
// set current field
procedure SetFieldName(const Value: string);
procedure UpdateField;
// make sure the field/fieldname is valid before we do stuff with it
procedure ValidateField;
procedure ResetEditingSource;
protected
// Testing Events
procedure ActiveChanged; override;
procedure EditingChanged; override;
procedure LayoutChanged; override;
procedure RecordChanged(aField: TField); override;
procedure UpdateData; override;
procedure FocusControl(aField: TFieldRef); Override;
public
constructor Create;
// for control intitiating db changes etc
function Edit: Boolean;
procedure Modified;
procedure Reset;
// Attached control
property Control: TComponent read FControl write FControl;
// Basic DB interfaces
property Field: TField read FField;
property FieldName: string read FFieldName write SetFieldName;
// Current State of DB
property CanModify: Boolean read GetCanModify;
property Editing: Boolean read FEditing;
property EditingSource: boolean read FEditingSource;
// Our Callbacks
property OnDataChange: TNotifyEvent read FOnDataChange write FOnDataChange;
property OnEditingChange: TNotifyEvent read FOnEditingChange write FOnEditingChange;
property OnUpdateData: TNotifyEvent read FOnUpdateData write FOnUpdateData;
property OnActiveChange: TNotifyEvent read FOnActiveChange write FOnActiveChange;
end;
{ TDBLookup }
{
TDBLookup component is typically owned by a Lookup control like
TDBLookupListBox or TDBLookupComboBox.
The ListSource is the other dataset TDataSource from which to retrieve the lookup data
The KeyField is the lookup key in the ListSource which corresponds to the DataField value
The ListField is the name of the field in the ListSource to list into the
Items property of the lookup control.
which data
}
TDBLookup = class(TComponent)
private
FControlLink: TFieldDataLink;
FControlItems: TStrings;
FListLink: TDataLink;
FListSource: TDataSource;
FLookupSource: TDataSource;
FDataFieldNames: string;
FKeyFieldNames: string;
FListFieldName: string;
FEmptyValue: string;
FDisplayEmpty: string;
FListFieldIndex: Integer;
FDataFields: TList; // Data Fields to lookup/edit
FKeyFields: TList; // Keyfields in lookup dataset
FListField: TField; // Result field in lookup dataset
FListKeys: array of Variant;
FNullValueKey: TShortcut;
FHasLookUpField: Boolean;
FLookUpFieldIsCached: Boolean;
FLookupCache: Boolean;
FInitializing: Boolean;
FScrollListDataset: Boolean;
procedure ActiveChange(Sender: TObject);
procedure DatasetChange(Sender: TObject);
procedure DoInitialize;
procedure FetchLookupData;
function GetKeyFieldName: string;
function GetListSource: TDataSource;
procedure SetKeyFieldName(const Value: string);
procedure SetListFieldName(const Value: string);
procedure SetListSource(Value: TDataSource);
procedure SetLookupCache(const Value: boolean);
function HandleNullKey(var Key: Word; Shift: TShiftState): Boolean;
protected
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
procedure Initialize(AControlDataLink: TFieldDataLink; AControlItems: TStrings);
function KeyFieldValue: Variant;
procedure UpdateData(ValueIndex: Integer);
function GetKeyValue(ValueIndex: Integer): Variant;
function GetKeyIndex: Integer;
function GetKeyIndex(const AKeyValue: Variant): Integer;
property ControlItems: TStrings read FControlItems write FControlItems;
property LookupCache: boolean read FLookupCache write SetLookupCache;
// properties to be published by owner control
// these are not used where data control Field is dbLookup
property KeyField: string read GetKeyFieldName write SetKeyFieldName;
property ListField: string read FListFieldName write SetListFieldName;
property ListFieldIndex: Integer read FListFieldIndex write FListFieldIndex default 0;
property ListSource: TDataSource read GetListSource write SetListSource;
property NullValueKey: TShortcut read FNullValueKey write FNullValueKey;
property ScrollListDataset: Boolean read FScrollListDataset write FScrollListDataset;
property EmptyValue : String read FEmptyValue write FEmptyVAlue;
property DisplayEmpty : String read FDisplayEmpty write FDisplayEmpty;
end;
{ TDBEdit }
TDBEdit = class(TCustomMaskEdit)
private
FDataLink: TFieldDataLink;
FCustomEditMask: Boolean;
FFocusedDisplay: boolean;
procedure DataChange(Sender: TObject);
procedure UpdateData(Sender: TObject);
function GetDataField: string;
function GetDataSource: TDataSource;
function GetField: TField;
procedure SetDataField(const Value: string);
procedure SetDataSource(Value: TDataSource);
procedure CMGetDataLink(var Message: TLMessage); message CM_GETDATALINK;
protected
function GetReadOnly: Boolean; override;
procedure SetReadOnly(Value: Boolean); override;
procedure KeyDown(var Key: Word; Shift: TShiftState); override;
procedure UTF8KeyPress(var UTF8Key: TUTF8Char); override;
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
function EditCanModify: Boolean; override;
function GetEditText: string; override;
procedure Change; override;
procedure Reset; override;
procedure WMSetFocus(var Message: TLMSetFocus); message LM_SETFOCUS;
procedure WMKillFocus(var Message: TLMKillFocus); message LM_KILLFOCUS;
procedure WndProc(var Message: TLMessage); override;
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
function ExecuteAction(AAction: TBasicAction): Boolean; override;
function UpdateAction(AAction: TBasicAction): Boolean; override;
property Field: TField read GetField;
published
property CustomEditMask: Boolean read FCustomEditMask write FCustomEditMask default False;
property DataField: string read GetDataField write SetDataField;
property DataSource: TDataSource read GetDataSource write SetDataSource;
property ReadOnly: Boolean read GetReadOnly write SetReadOnly default False;
property Align;
property Alignment;
property Anchors;
property AutoSelect;
property AutoSize;
property BiDiMode;
property BorderSpacing;
property BorderStyle;
property CharCase;
property Color;
property Constraints;
property DoubleBuffered;
property DragCursor;
property DragKind;
property DragMode;
property Enabled;
property EditMask;
property Font;
property MaxLength;
property ParentBiDiMode;
property ParentColor;
property ParentDoubleBuffered;
property ParentFont;
property ParentShowHint;
property PasswordChar;
property PopupMenu;
property ShowHint;
property TabOrder;
property TabStop;
property TextHint;
property Visible;
property OnChange;
property OnClick;
property OnContextPopup;
property OnDblClick;
property OnDragDrop;
property OnDragOver;
property OnEditingDone;
property OnEndDrag;
property OnEnter;
property OnExit;
property OnKeyDown;
property OnKeyPress;
property OnKeyUp;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnStartDrag;
property OnUTF8KeyPress;
end;
{ TDBText }
TDBText = class(TCustomLabel)
private
FDataLink: TFieldDataLink;
procedure DataChange(Sender: TObject);
function GetDataField: string;
function GetDataSource: TDataSource;
function GetField: TField;
procedure SetDataField(const Value: string);
procedure SetDataSource(Value: TDataSource);
procedure CMGetDataLink(var Message: TLMessage); message CM_GETDATALINK;
protected
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
class procedure WSRegisterClass; override;
procedure Loaded; override;
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
function ExecuteAction(AAction: TBasicAction): Boolean; override;
function UpdateAction(AAction: TBasicAction): Boolean; override;
property Field: TField read GetField;
published
property Align;
property Alignment;
property Anchors;
property AutoSize;
property BidiMode;
property BorderSpacing;
property Color;
property Constraints;
property DataField: string read GetDataField write SetDataField;
property DataSource: TDataSource read GetDataSource write SetDataSource;
property DragCursor;
property DragKind;
property DragMode;
property Enabled;
property FocusControl;
property Font;
property Layout;
property OptimalFill;
property ParentBidiMode;
property ParentColor;
property ParentFont;
property ParentShowHint;
property PopupMenu;
property ShowAccelChar;
property ShowHint;
property Transparent;
property Visible;
property WordWrap;
property OnClick;
property OnDblClick;
property OnDragDrop;
property OnDragOver;
property OnEndDrag;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnChangeBounds;
property OnContextPopup;
property OnResize;
property OnStartDrag;
end;
{ TCustomDBListBox }
TCustomDBListBox = class(TCustomListBox)
private
function GetDataField: string;
function GetDataSource: TDataSource;
function GetField: TField;
function GetReadOnly: Boolean;
procedure SetReadOnly(Value: Boolean);
procedure SetDataField(const Value: string);
procedure SetDataSource(Value: TDataSource);
procedure CMGetDataLink(var Message: TLMessage); message CM_GETDATALINK;
protected
FDataLink: TFieldDataLink;
procedure DataChange(Sender: TObject); virtual; abstract;
procedure KeyDown(var Key: Word; Shift: TShiftState); override;
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
procedure UpdateData(Sender: TObject); virtual; abstract;
// we need to override the Items Write method for db aware.
procedure SetItems(Values : TStrings); override;
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
function ExecuteAction(AAction: TBasicAction): Boolean; override;
function UpdateAction(AAction: TBasicAction): Boolean; override;
property Field: TField read GetField;
property DataField: string read GetDataField write SetDataField;
property DataSource: TDataSource read GetDataSource write SetDataSource;
//same as dbedit need to match the datalink status
property ReadOnly: Boolean read GetReadOnly write SetReadOnly default False;
end;
{ TDBListBox }
TDBListBox = class(TCustomDBListBox)
protected
procedure DataChange(Sender: TObject); override;
procedure DoSelectionChange(User: Boolean); override;
procedure UpdateData(Sender: TObject); override;
public
procedure EditingDone; override;
published
property Align;
property Anchors;
property BiDiMode;
property BorderSpacing;
property BorderStyle;
property Color;
property Constraints;
property DataField;
property DataSource;
property DoubleBuffered;
property DragCursor;
property DragKind;
property DragMode;
property Enabled;
property ExtendedSelect;
property Font;
property ItemHeight;
property Items;
property MultiSelect;
property Options;
property ParentBiDiMode;
property ParentDoubleBuffered;
property ParentShowHint;
property PopupMenu;
property ReadOnly;
property ShowHint;
property Sorted;
property Style;
property TabOrder;
property TabStop;
property TopIndex;
property Visible;
property OnClick;
property OnContextPopup;
property OnDblClick;
property OnDragDrop;
property OnDragOver;
property OnDrawItem;
property OnEndDrag;
property OnEnter;
property OnExit;
property OnKeyPress;
property OnKeyDown;
property OnKeyUp;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnResize;
property OnStartDrag;
property OnUTF8KeyPress;
end;
{ TDBLookupListBox }
TDBLookupListBox = class(TCustomDBListBox)
private
FLookup: TDBLookup;
procedure ActiveChange(Sender: TObject);
function GetDisplayEmpty: String;
function GetEmptyValue: String;
function GetKeyField: string;
function GetKeyValue: Variant;
function GetListField: string;
function GetListFieldIndex: Integer;
function GetListSource: TDataSource;
function GetLookupCache: boolean;
function GetNullValueKey: TShortCut;
function GetScrollListDataset: Boolean;
procedure SetDisplayEmpty(AValue: String);
procedure SetEmptyValue(AValue: String);
procedure SetKeyField(const Value: string);
procedure SetKeyValue(const AValue: Variant);
procedure SetListField(const Value: string);
procedure SetListFieldIndex(const Value: Integer);
procedure SetListSource(const Value: TDataSource);
procedure SetLookupCache(const Value: boolean);
procedure SetNullValueKey(const AValue: TShortCut);
procedure SetScrollListDataset(AValue: Boolean);
procedure UpdateLookup;
protected
procedure DataChange(Sender: TObject); override;
procedure DoSelectionChange(User: Boolean); override;
procedure InitializeWnd; override;
procedure DestroyWnd; override;
procedure KeyDown(var Key: Word; Shift: TShiftState); override;
procedure Loaded; override;
procedure UpdateData(Sender: TObject); override;
function IsUnbound: boolean;
public
constructor Create(AOwner: TComponent); override;
property KeyValue: Variant read GetKeyValue write SetKeyValue;
published
property Align;
property Anchors;
property BiDiMode;
property BorderSpacing;
property BorderStyle;
property Color;
property Constraints;
property DataField;
property DataSource;
property DoubleBuffered;
property DragCursor;
property DragKind;
property DragMode;
property Enabled;
property Font;
property KeyField: string read GetKeyField write SetKeyField;
property ListField: string read GetListField write SetListField;
property ListFieldIndex: Integer read GetListFieldIndex write SetListFieldIndex;
property ListSource: TDataSource read GetListSource write SetListSource;
property LookupCache: boolean read GetLookupCache write SetLookupCache;
property NullValueKey: TShortCut read GetNullValueKey write SetNullValueKey default 0;
property EmptyValue: String read GetEmptyValue write SetEmptyValue;
property DisplayEmpty: String read GetDisplayEmpty write SetDisplayEmpty;
property Options;
property ParentBiDiMode;
property ParentDoubleBuffered;
property ParentShowHint;
property PopupMenu;
property ReadOnly;
property ScrollListDataset: Boolean read GetScrollListDataset write SetScrollListDataset default False;
property ShowHint;
property Sorted;
property TabOrder;
property TabStop;
property TopIndex;
property Visible;
property OnClick;
property OnContextPopup;
property OnDblClick;
property OnDragDrop;
property OnDragOver;
property OnEditingDone;
property OnEndDrag;
property OnEnter;
property OnExit;
property OnKeyPress;
property OnKeyDown;
property OnKeyUp;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnResize;
property OnStartDrag;
property OnUTF8KeyPress;
end;
{ TDBRadioGroup }
TDBRadioGroup = class(TCustomRadioGroup)
private
FDataLink: TFieldDataLink;
FOnChange: TNotifyEvent;
FValue: string;
FValues: TStrings;
FInSetValue: boolean;
function GetDataField: string;
function GetDataSource: TDataSource;
function GetField: TField;
function GetReadOnly: Boolean;
procedure SetDataField(const AValue: string);
procedure SetDataSource(const AValue: TDataSource);
procedure SetItems(const AValue: TStrings);
procedure SetReadOnly(const AValue: Boolean);
procedure SetValue(const AValue: string);
procedure SetValues(const AValue: TStrings);
procedure CMGetDataLink(var Message: TLMessage); message CM_GETDATALINK;
protected
procedure Change; virtual;
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
procedure DataChange(Sender: TObject);
procedure UpdateData(Sender: TObject);
property DataLink: TFieldDataLink read FDataLink;
function GetButtonValue(Index: Integer): string;
procedure UpdateRadioButtonStates; override;
public
constructor Create(TheOwner: TComponent); override;
destructor Destroy; override;
procedure EditingDone; override;
function ExecuteAction(AAction: TBasicAction): Boolean; override;
function UpdateAction(AAction: TBasicAction): Boolean; override;
property Field: TField read GetField;
property ItemIndex;
property Value: string read FValue write SetValue;
published
property Align;
property Anchors;
property AutoFill;
property AutoSize;
property BiDiMode;
property BorderSpacing;
property Caption;
property ChildSizing;
property Color;
property ColumnLayout;
property Columns;
property Constraints;
property DataField: string read GetDataField write SetDataField;
property DataSource: TDataSource read GetDataSource write SetDataSource;
property DoubleBuffered;
property DragCursor;
property DragMode;
property Enabled;
property Font;
property Items write SetItems;
property ParentBiDiMode;
property ParentColor;
property ParentDoubleBuffered;
property ParentFont;
property ParentShowHint;
property PopupMenu;
property ReadOnly: Boolean read GetReadOnly write SetReadOnly default False;
property ShowHint;
property TabOrder;
property TabStop;
property Values: TStrings read FValues write SetValues;
property Visible;
property OnChange: TNotifyEvent read FOnChange write FOnChange;
property OnChangeBounds;
property OnClick;
property OnContextPopup;
property OnDragDrop;
property OnDragOver;
property OnEndDrag;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnResize;
property OnStartDrag;
end;
{ TDBCheckBox }
TDBCheckBox = class(TCustomCheckBox)
private
FDataLink: TFieldDataLink;
FValueChecked: string;
FValueUnchecked: string;
function GetDataField: string;
function GetDataSource: TDataSource;
function GetField: TField;
function GetReadOnly: Boolean;
procedure SetDataField(const AValue: string);
procedure SetDataSource(const AValue: TDataSource);
procedure SetReadOnly(const AValue: Boolean);
procedure SetValueChecked(const AValue: string);
procedure SetValueUnchecked(const AValue: string);
function NonDefaultValueChecked: Boolean;
function NonDefaultValueUnchecked: Boolean;
procedure CMGetDataLink(var Message: TLMessage); message CM_GETDATALINK;
protected
function GetFieldCheckState: TCheckBoxState; virtual;
procedure DataChange(Sender: TObject);
procedure DoOnChange; override;
procedure UpdateData(Sender: TObject);
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
public
constructor Create(TheOwner: TComponent); override;
destructor Destroy; override;
function ExecuteAction(AAction: TBasicAction): Boolean; override;
function UpdateAction(AAction: TBasicAction): Boolean; override;
property Checked;
property Field: TField read GetField;
property State;
published
property Action;
property Align;
property Alignment;
property AllowGrayed;
property Anchors;
property AutoSize;
property BiDiMode;
property BorderSpacing;
property Caption;
property Color;
property Constraints;
property DataField: string read GetDataField write SetDataField;
property DataSource: TDataSource read GetDataSource write SetDataSource;
property DoubleBuffered;
property DragCursor;
property DragKind;
property DragMode;
property Enabled;
property Font;
property Hint;
property ParentBiDiMode;
property ParentColor;
property ParentDoubleBuffered;
property ParentFont;
property ParentShowHint;
property PopupMenu;
property ReadOnly: Boolean read GetReadOnly write SetReadOnly default False;
property ShowHint;
property TabOrder;
property TabStop;
property ValueChecked: string read FValueChecked write SetValueChecked stored NonDefaultValueChecked;
property ValueUnchecked: string read FValueUnchecked write SetValueUnchecked stored NonDefaultValueUnchecked;
property Visible;
property OnChange;
property OnClick;
property OnContextPopup;
property OnDragDrop;
property OnDragOver;
property OnEndDrag;
property OnEnter;
property OnExit;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnStartDrag;
end;
{ TCustomDBComboBox }
TCustomDBComboBox = class(TCustomComboBox)
private
FDataLink: TFieldDataLink;
FDetectedEvents: Word;
function GetDataField: string;
function GetDataSource: TDataSource;
function GetField: TField;
function GetReadOnly: Boolean;
procedure SetDataField(const AValue: string);
procedure SetDataSource(const AValue: TDataSource);
procedure SetReadOnly(const AValue: Boolean);
procedure CMGetDataLink(var Message: TLMessage); message CM_GETDATALINK;
protected
function DoEdit: boolean; virtual;
procedure DoOnCloseUp; virtual;
procedure DoOnSelect; virtual;
procedure DoOnChange; virtual;
procedure LMDeferredEdit(var Message: TLMessage); message LM_DEFERREDEDIT;
property DetectedEvents: Word read FDetectedEvents;
protected
procedure CloseUp; override;
Procedure Select; override;
procedure DataChange(Sender: TObject); virtual; abstract;
function DoMouseWheel(Shift: TShiftState; WheelDelta: Integer; MousePos: TPoint): Boolean; override;
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
procedure Change; override;
procedure KeyDown(var Key: Word; Shift: TShiftState); override;
procedure UpdateData(Sender: TObject); virtual; abstract;
procedure UpdateRecord;
procedure WndProc(var Message: TLMessage); override;
public
constructor Create(TheOwner: TComponent); override;
destructor Destroy; override;
function ExecuteAction(AAction: TBasicAction): Boolean; override;
function UpdateAction(AAction: TBasicAction): Boolean; override;
procedure EditingDone; override;
property Field: TField read GetField;
property Text;
property ItemIndex;
property DataField: string read GetDataField write SetDataField;
property DataSource: TDataSource read GetDataSource write SetDataSource;
property ReadOnly: Boolean read GetReadOnly write SetReadOnly default False;
end;
{ TDBComboBox }
TDBComboBox = class(TCustomDBComboBox)
protected
procedure DataChange(Sender: TObject); override;
procedure KeyPress(var Key: char); override;
procedure UpdateData(Sender: TObject); override;
published
property Align;
property Anchors;
property ArrowKeysTraverseList;
property AutoComplete;
property AutoCompleteText;
property AutoDropDown;
property AutoSelect;
property AutoSize;
property BiDiMode;
property BorderSpacing;
property BorderStyle;
property CharCase;
property Color;
property Constraints;
property DataField;
property DataSource;
property DoubleBuffered;
property DragCursor;
property DragKind;
property DragMode;
property DropDownCount;
property Enabled;
property Font;
property ItemHeight;
property Items;
property ItemWidth;
property MaxLength default -1;
property ParentBiDiMode;
property ParentColor;
property ParentDoubleBuffered;
property ParentFont;
property ParentShowHint;
property PopupMenu;
property ReadOnly;
property ShowHint;
property Sorted;
property Style;
property TabOrder;
property TabStop;
property Visible;
property OnChange;
property OnChangeBounds;
property OnClick;
property OnCloseUp;
property OnContextPopup;
property OnDblClick;
property OnDragDrop;
property OnDragOver;
property OnDrawItem;
property OnDropDown;
property OnEditingDone;
property OnEndDrag;
property OnEnter;
property OnExit;
property OnKeyDown;
property OnKeyPress;
property OnKeyUp;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnSelect;
property OnStartDrag;
property OnUTF8KeyPress;
end;
{ TDBLookupComboBox }
TDBLookupComboBox = class(TCustomDBComboBox)
protected
procedure DefineProperties(Filer: TFiler); override;
function DoEdit: boolean; override;
procedure DoAutoCompleteSelect; override;
function IsUnbound: boolean;
private
FLookup: TDBLookup;
procedure ActiveChange(Sender: TObject);
function GetDisplayEmpty: String;
function GetDropDownRows: Integer;
function GetEmptyValue: String;
function GetKeyField: string;
function GetKeyValue: variant;
function GetListField: string;
function GetListFieldIndex: Integer;
function GetListSource: TDataSource;
function GetLookupCache: boolean;
function GetNullValueKey: TShortCut;
function GetScrollListDataset: Boolean;
procedure ReadDropDownCount(Reader: TReader);
procedure SetDisplayEmpty(AValue: String);
procedure SetDropDownRows(AValue: Integer);
procedure SetEmptyValue(AValue: String);
procedure SetKeyField(const Value: string);
procedure SetKeyValue(const AValue: variant);
procedure SetListField(const Value: string);
procedure SetListFieldIndex(const Value: Integer);
procedure SetListSource(const Value: TDataSource);
procedure SetLookupCache(const Value: boolean);
procedure SetNullValueKey(const AValue: TShortCut);
procedure SetScrollListDataset(AValue: Boolean);
procedure UpdateLookup;
procedure UpdateItemIndex;
protected
procedure InitializeWnd; override;
procedure DestroyWnd; override;
procedure KeyDown(var Key: Word; Shift: TShiftState); override;
procedure UTF8KeyPress(var UTF8Key: TUTF8Char); override;
procedure Loaded; override;
procedure UpdateData(Sender: TObject); override;
procedure DataChange(Sender: TObject); override;
procedure DoOnSelect; override;
public
constructor Create(AOwner: TComponent); override;
property KeyValue: variant read GetKeyValue write SetKeyValue;
property DropDownCount; deprecated 'Use DropDownRows';
published
property Align;
property Anchors;
property ArrowKeysTraverseList;
property AutoComplete;
property AutoDropDown;
property AutoSelect;
property AutoSize;
property BiDiMode;
property BorderSpacing;
property BorderStyle;
property CharCase;
property Color;
property Constraints;
property DataField;
property DataSource;
property DoubleBuffered;
property DragCursor;
property DragKind;
property DragMode;
property DropDownRows: Integer read GetDropDownRows write SetDropDownRows default 7;
property Enabled;
property Font;
property KeyField: string read GetKeyField write SetKeyField;
property ListField: string read GetListField write SetListField;
property ListFieldIndex: Integer read GetListFieldIndex write SetListFieldIndex;
property ListSource: TDataSource read GetListSource write SetListSource;
property LookupCache: boolean read GetLookupCache write SetLookupCache;
property NullValueKey: TShortCut read GetNullValueKey write SetNullValueKey default 0;
property EmptyValue: String read GetEmptyValue write SetEmptyValue;
property DisplayEmpty: String read GetDisplayEmpty write SetDisplayEmpty;
property ParentBiDiMode;
property ParentColor;
property ParentDoubleBuffered;
property ParentFont;
property ParentShowHint;
property PopupMenu;
property ReadOnly;
property ScrollListDataset: Boolean read GetScrollListDataset write SetScrollListDataset default False;
property ShowHint;
property Sorted;
property Style;
property TabOrder;
property TabStop;
property Visible;
property OnChange;
property OnChangeBounds;
property OnClick;
property OnCloseUp;
property OnContextPopup;
property OnDblClick;
property OnDragDrop;
property OnDragOver;
property OnDrawItem;
property OnDropDown;
property OnEditingDone;
property OnEndDrag;
property OnEnter;
property OnExit;
property OnKeyDown;
property OnKeyPress;
property OnKeyUp;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnSelect;
property OnStartDrag;
property OnUTF8KeyPress;
end;
{ TDBMemo }
TDBMemo = class(TCustomMemo)
private
FDataLink: TFieldDataLink;
FAutoDisplay: Boolean;
FDBMemoFocused: Boolean;
FDBMemoLoaded: Boolean;
function GetDataField: string;
function GetDataSource: TDataSource;
function GetField: TField;
procedure SetAutoDisplay(const AValue: Boolean);
procedure SetDataField(const AValue: string);
procedure SetDataSource(const AValue: TDataSource);
procedure CMGetDataLink(var Message: TLMessage); message CM_GETDATALINK;
protected
function GetReadOnly: Boolean; override;
procedure SetReadOnly(AValue: Boolean); override;
procedure DataChange(Sender: TObject);
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
procedure UpdateData(Sender: TObject);
procedure Change; override;
procedure KeyDown(var Key: Word; Shift: TShiftState); override;
procedure KeyPress(var Key:Char); override;
procedure WndProc(var Message : TLMessage); override;
class procedure WSRegisterClass; override;
public
constructor Create(TheOwner: TComponent); override;
destructor Destroy; override;
procedure EditingDone; override;
procedure LoadMemo; virtual;
function ExecuteAction(AAction: TBasicAction): Boolean; override;
function UpdateAction(AAction: TBasicAction): Boolean; override;
property Field: TField read GetField;
published
property Align;
property Alignment;
property Anchors;
property AutoDisplay: Boolean read FAutoDisplay write SetAutoDisplay default True;
property BiDiMode;
property BorderSpacing;
property BorderStyle;
property CharCase;
property Color;
property Constraints;
property DataField: string read GetDataField write SetDataField;
property DataSource: TDataSource read GetDataSource write SetDataSource;
property DoubleBuffered;
property DragCursor;
property DragKind;
property DragMode;
property Enabled;
property Font;
property MaxLength;
property ParentBiDiMode;
property ParentDoubleBuffered;
property ParentFont;
property ParentShowHint;
property PopupMenu;
property ReadOnly: Boolean read GetReadOnly write SetReadOnly default False;
property ScrollBars;
property ShowHint;
property TabOrder;
property Tabstop;
property Visible;
property WantReturns;
property WantTabs;
property WordWrap;
property OnChange;
property OnClick;
property OnContextPopup;
property OnDblClick;
property OnDragDrop;
property OnDragOver;
property OnEditingDone;
property OnEndDrag;
property OnEnter;
property OnExit;
property OnKeyDown;
property OnKeyPress;
property OnKeyUp;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnResize;
property OnStartDrag;
property OnUTF8KeyPress;
end;
{ TDBGroupBox }
TDBGroupBox = class(TCustomGroupBox)
private
FDataLink: TFieldDataLink;
function GetDataField: string;
function GetDataSource: TDataSource;
function GetField: TField;
procedure SetDataField(const AValue: string);
procedure SetDataSource(const AValue: TDataSource);
procedure CMGetDataLink(var Message: TLMessage); message CM_GETDATALINK;
protected
procedure DataChange(Sender: TObject);
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
public
constructor Create(TheOwner: TComponent); override;
destructor Destroy; override;
function ExecuteAction(AAction: TBasicAction): Boolean; override;
function UpdateAction(AAction: TBasicAction): Boolean; override;
property Field: TField read GetField;
published
property Align;
property Anchors;
property BiDiMode;
property BorderSpacing;
property Caption;
property ClientHeight;
property ClientWidth;
property Color;
property Constraints;
property Cursor;
property DataField: string read GetDataField write SetDataField;
property DataSource: TDataSource read GetDataSource write SetDataSource;
property DoubleBuffered;
property DragCursor;
property DragKind;
property DragMode;
property Enabled;
property Font;
property ParentBiDiMode;
property ParentColor;
property ParentDoubleBuffered;
property ParentFont;
property ParentShowHint;
property PopupMenu;
property ShowHint;
property TabOrder;
property TabStop;
property Visible;
property OnClick;
property OnContextPopup;
property OnDblClick;
property OnDragDrop;
property OnDragOver;
property OnEndDrag;
property OnEnter;
property OnExit;
property OnKeyDown;
property OnKeyPress;
property OnKeyUp;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnResize;
property OnStartDrag;
property OnUTF8KeyPress;
end;
{ TDBImage }
TOnDBImageRead = procedure(Sender: TObject; S: TStream; var GraphExt : string) of object;
TOnDBImageWrite = procedure(Sender: TObject; S: TStream; GraphExt : string) of object;
TDBImage = class(TCustomImage)
private
FDataLink: TFieldDataLink;
FAutoDisplay: Boolean;
FOnDBImageRead: TOnDBImageRead;
FOnDBImageWrite: TOnDBImageWrite;
FQuickDraw: Boolean;
FPictureLoaded: boolean;
FUpdatingRecord: boolean;
FWriteHeader: Boolean;
function GetDataField: string;
function GetDataSource: TDataSource;
function GetField: TField;
function GetReadOnly: Boolean;
procedure SetAutoDisplay(const AValue: Boolean);
procedure SetDataField(const AValue: string);
procedure SetDataSource(const AValue: TDataSource);
procedure SetReadOnly(const AValue: Boolean);
procedure CMGetDataLink(var Message: TLMessage); message CM_GETDATALINK;
protected
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
procedure DataChange(Sender: TObject);
procedure UpdateData(Sender: TObject); virtual;
procedure PictureChanged(Sender: TObject); override;
class procedure WSRegisterClass; override;
procedure DoCopyToClipboard;
public
constructor Create(TheOwner: TComponent); override;
destructor Destroy; override;
function ExecuteAction(AAction: TBasicAction): Boolean; override;
function UpdateAction(AAction: TBasicAction): Boolean; override;
property Field: TField read GetField;
procedure Change; virtual;
procedure LoadPicture; virtual;
procedure CopyToClipboard;
procedure CutToClipboard;
procedure PasteFromClipboard;
property PictureLoaded : boolean read FPictureLoaded;
published
property Align;
property Anchors;
property AntialiasingMode;
property AutoDisplay: Boolean read FAutoDisplay write SetAutoDisplay default True;
property AutoSize;
property BorderSpacing;
property Center;
property Constraints;
property DataField: string read GetDataField write SetDataField;
property DataSource: TDataSource read GetDataSource write SetDataSource;
property DragCursor;
property DragKind;
property DragMode;
property KeepOriginXWhenClipped;
property KeepOriginYWhenClipped;
property ParentShowHint;
property Proportional;
property QuickDraw: Boolean read FQuickDraw write FQuickDraw default True;
property ReadOnly: Boolean read GetReadOnly write SetReadOnly default False;
property ShowHint;
property Stretch;
property StretchInEnabled;
property StretchOutEnabled;
property Transparent;
property Visible;
property WriteHeader: Boolean read FWriteHeader write FWriteHeader default True;
property OnClick;
property OnContextPopup;
property OnDblClick;
property OnDBImageRead: TOnDBImageRead read FOnDBImageRead write FOnDBImageRead;
property OnDBImageWrite: TOnDBImageWrite read FOnDBImageWrite write FOnDBImageWrite;
property PopupMenu;
property OnDragDrop;
property OnDragOver;
property OnEndDrag;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnResize;
property OnStartDrag;
end;
{ TDBCalendar }
TDBCalendar = class(TCalendar)
private
FDataLink: TFieldDataLink;
procedure DataChange(Sender: TObject);
procedure UpdateData(Sender: TObject);
function GetDataField: string;
function GetDataSource: TDataSource;
function GetField: TField;
function GetReadOnly: Boolean;
procedure SetReadOnly(Value: Boolean);
procedure SetDate(const AValue: String);
procedure SetDataField(const Value: string);
procedure SetDataSource(Value: TDataSource);
procedure UpdateDate(const AValue: string);
procedure CMGetDataLink(var Message: TLMessage); message CM_GETDATALINK;
protected
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
public
constructor Create(TheOwner: TComponent); override;
destructor Destroy; override;
procedure EditingDone; override;
function ExecuteAction(AAction: TBasicAction): Boolean; override;
function UpdateAction(AAction: TBasicAction): Boolean; override;
property Field: TField read GetField;
published
property BorderSpacing;
property Constraints;
property DataField: string read GetDataField write SetDataField;
property DataSource: TDataSource read GetDataSource write SetDataSource;
Property Date write SetDate stored False;
property ReadOnly: Boolean read GetReadOnly write SetReadOnly default False;
property DisplaySettings stored False;
property DoubleBuffered;
property DragCursor;
property DragMode;
property ParentDoubleBuffered;
property Visible;
property OnClick;
property OnContextPopup;
property OnDragDrop;
property OnDragOver;
property OnEndDrag;
property OnMouseMove;
property OnMouseDown;
property OnDayChanged;
property OnMonthChanged;
property OnStartDrag;
property OnYearChanged;
end;
{ TDBCustomNavigator }
type
TDBNavButton = class;
TDBNavFocusableButton = class;
TDBNavDataLink = class;
TDBNavGlyph = (ngEnabled, ngDisabled);
TDBNavButtonType = (nbFirst, nbPrior, nbNext, nbLast,
nbInsert, nbDelete, nbEdit, nbPost, nbCancel, nbRefresh);
TDBNavButtonSet = set of TDBNavButtonType;
TDBNavButtonStyle = set of (nsAllowTimer, nsFocusRect);
TDBNavButtonDirection = (nbdHorizontal,nbdVertical);
TDBNavigatorOption = (navFocusableButtons);
TDBNavigatorOptions = set of TDBNavigatorOption;
// for Delphi compatibility
TNavigateBtn = TDBNavButtonType;
TDBNavClickEvent = procedure(Sender: TObject;
Button: TDBNavButtonType) of object;
const
DefaultDBNavigatorButtons = [nbFirst, nbPrior, nbNext, nbLast,
nbInsert, nbDelete, nbEdit, nbPost, nbCancel, nbRefresh];
DBNavButtonResourceName: array[TDBNavButtonType] of string = (
{ nbFirst } 'DBNavFirst',
{ nbPrior } 'DBNavPrior',
{ nbNext } 'DBNavNext',
{ nbLast } 'DBNavLast',
{ nbInsert } 'DBNavInsert',
{ nbDelete } 'DBNavDelete',
{ nbEdit } 'DBNavEdit',
{ nbPost } 'DBNavPost',
{ nbCancel } 'DBNavCancel',
{ nbRefresh } 'DBNavRefresh'
);
type
{ TDBCustomNavigator }
TDBCustomNavigator = class(TCustomPanel)
private
FBeforeAction: TDBNavClickEvent;
FDataLink: TDBNavDataLink;
FDirection: TDBNavButtonDirection;
FOnNavClick: TDBNavClickEvent;
FVisibleButtons: TDBNavButtonSet;
FDefaultHints: TStrings;
FHints: TStrings;
FUpdateButtonsLock: integer;
FOriginalHints: String;
FOptions: TDBNavigatorOptions;
FFlat: Boolean;
FConfirmDelete: Boolean;
FUpdateButtonsNeeded: boolean;
FShowButtonHints: boolean;
FImages: TCustomImageList;
FImageChangeLink: TChangeLink;
procedure DefaultHintsChanged(Sender: TObject);
function GetDataSource: TDataSource;
function GetHints: TStrings;
procedure SetDataSource(const AValue: TDataSource);
procedure SetDirection(const AValue: TDBNavButtonDirection);
procedure SetFlat(const AValue: Boolean);
procedure SetHints(const AValue: TStrings);
procedure SetImages(AValue: TCustomImageList);
procedure SetOptions(AValue: TDBNavigatorOptions);
procedure SetShowButtonHints(const AValue: boolean);
procedure SetVisibleButtons(const AValue: TDBNavButtonSet);
procedure CMGetDataLink(var Message: TLMessage); message CM_GETDATALINK;
procedure ImageListChange(Sender: TObject);
protected
Buttons: array[TDBNavButtonType] of TDBNavButton;
FocusableButtons: array[TDBNavButtonType] of TDBNavFocusableButton;
procedure DataChanged; virtual;
procedure EditingChanged; virtual;
procedure ActiveChanged; virtual;
procedure Loaded; override;
procedure Notification(AComponent: TComponent; Operation: TOperation); override;
procedure UpdateButtons; virtual;
procedure UpdateHints; virtual;
procedure HintsChanged(Sender: TObject); virtual;
procedure ButtonClickHandler(Sender: TObject); virtual;
class function GetControlClassDefaultSize: TSize; override;
procedure BeginUpdateButtons; virtual;
procedure EndUpdateButtons; virtual;
procedure SetEnabled(Value: Boolean); override;
public
constructor Create(TheOwner: TComponent); override;
destructor Destroy; override;
procedure BtnClick(Index: TNavigateBtn); virtual;
function VisibleButtonCount: integer; virtual;
public
property BeforeAction: TDBNavClickEvent read FBeforeAction write FBeforeAction;
property ConfirmDelete: Boolean read FConfirmDelete write FConfirmDelete default True;
property DataSource: TDataSource read GetDataSource write SetDataSource;
property Direction: TDBNavButtonDirection read FDirection write SetDirection default nbdHorizontal;
property Flat: Boolean read FFlat write SetFlat default False;
property Hints: TStrings read GetHints write SetHints;
property Options: TDBNavigatorOptions read FOptions write SetOptions;
property OnClick: TDBNavClickEvent read FOnNavClick write FOnNavClick;
property VisibleButtons: TDBNavButtonSet read FVisibleButtons
write SetVisibleButtons default DefaultDBNavigatorButtons;
property ShowButtonHints: boolean read FShowButtonHints write SetShowButtonHints default true;
property Images: TCustomImageList read FImages write SetImages;
end;
{ TDBNavButton }
TDBNavButton = class(TSpeedButton)
private
FIndex: TDBNavButtonType;
FNavStyle: TDBNavButtonStyle;
protected
public
destructor Destroy; override;
property NavStyle: TDBNavButtonStyle read FNavStyle write FNavStyle;
property Index: TDBNavButtonType read FIndex write FIndex;
end;
{ TDBNavFocusableButton }
TDBNavFocusableButton = class(TBitBtn)
private
FIndex: TDBNavButtonType;
FNavStyle: TDBNavButtonStyle;
public
property NavStyle: TDBNavButtonStyle read FNavStyle write FNavStyle;
property Index: TDBNavButtonType read FIndex write FIndex;
end;
{ TNavDataLink }
TDBNavDataLink = class(TDataLink)
private
FNavigator: TDBCustomNavigator;
protected
procedure EditingChanged; override;
procedure DataSetChanged; override;
procedure ActiveChanged; override;
public
constructor Create(TheNavigator: TDBCustomNavigator);
end;
{ TDBNavigator }
TDBNavigator = class(TDBCustomNavigator)
published
property Align default alNone;
property Alignment;
property Anchors;
property AutoSize;
property BidiMode;
property BeforeAction;
property BevelInner;
property BevelOuter;
property BevelWidth;
property BorderSpacing;
property BorderStyle;
property BorderWidth;
property Caption;
property ChildSizing;
property ClientHeight;
property ClientWidth;
property Color default clBackground;
property Constraints;
property ConfirmDelete;
property DataSource;
property Direction;
property DoubleBuffered;
property DragCursor;
property DragMode;
property Enabled;
property Flat;
property Font;
property Hints;
property Options;
property ParentBidiMode;
property ParentColor;
property ParentDoubleBuffered;
property ParentFont;
property ParentShowHint;
property PopupMenu;
property ShowHint;
property TabOrder;
property TabStop default False;
property Visible;
property VisibleButtons;
property Images;
property OnClick;
property OnContextPopup;
property OnDblClick;
property OnDragDrop;
property OnDragOver;
property OnEndDrag;
property OnEnter;
property OnExit;
property OnMouseDown;
property OnMouseEnter;
property OnMouseLeave;
property OnMouseMove;
property OnMouseUp;
property OnMouseWheel;
property OnMouseWheelDown;
property OnMouseWheelUp;
property OnResize;
property OnStartDrag;
end;
procedure ChangeDataSource(AControl: TControl; Link: TDataLink;
NewDataSource: TDataSource);
procedure Register;
implementation
{$R lcl_dbnav_images.res}
uses
InterfaceBase, Clipbrd;
var
FieldClasses: TFpList;
procedure RegField(const FieldClass: TFieldClass);
begin
if FieldClasses = nil then FieldClasses := TFpList.Create;
if (FieldClass <> Nil) And (FieldClasses.IndexOf(FieldClass) = -1) then
begin
FieldClasses.Add(FieldClass);
RegisterNoIcon([FieldClass]);
RegisterClass(FieldClass);
end;
end;
procedure RegFields(const AFieldClasses: array of TFieldClass);
var I: Integer;
begin
for I := Low(AFieldClasses) to High(AFieldClasses) do
RegField(AFieldClasses[I]);
end;
procedure ChangeDataSource(AControl: TControl; Link: TDataLink;
NewDataSource: TDataSource);
begin
if Link.DataSource=NewDataSource then exit;
if Link.DataSource<>nil then
Link.DataSource.RemoveFreeNotification(AControl);
Link.DataSource:=NewDataSource;
if Link.DataSource<>nil then
Link.DataSource.FreeNotification(AControl);
end;
function FieldIsEditable(Field: TField): boolean;
begin
result := (Field<>nil) and (not Field.Calculated) and
(Field.DataType<>ftAutoInc) and (Field.FieldKind<>fkLookup)
end;
function FieldCanAcceptKey(Field: TField; AKey: char): boolean;
begin
Result := FieldIsEditable(Field) and Field.IsValidChar(AKey);
end;
procedure Register;
begin
RegisterComponents('Data Controls',[TDBNavigator,TDBText,TDBEdit,TDBMemo,
TDBImage,TDBListBox,TDBLookupListBox,TDBComboBox,TDBLookupComboBox,
TDBCheckBox, TDBRadioGroup, TDBCalendar,TDBGroupBox]);
RegFields(DefaultFieldClasses);
RegField(TIntegerField);
end;
function TFieldDataLink.FieldCanModify: boolean;
var
FieldList: TList;
i: Integer;
begin
result := Assigned(FField);
if not result then
exit;
if FField.FieldKind=fkLookup then
begin
FieldList := TList.Create;
try
DataSet.GetFieldList(FieldList, FField.KeyFields);
result := (FieldList.Count>0);
i := 0;
while result and (i<FieldList.Count) do
begin
result := TField(FieldList[i]).CanModify;
inc(i);
end;
finally
FieldList.Free;
end;
end else
result := FField.CanModify;
end;
function TFieldDataLink.IsKeyField(aField: TField): Boolean;
var
KeyFieldName, KeyFields: String;
StrPos: Integer;
begin
KeyFields := FField.KeyFields;
StrPos := 1;
while StrPos <= Length(KeyFields) do
begin
KeyFieldName := ExtractFieldName(KeyFields, StrPos);
if SameText(aField.FieldName, KeyFieldName) then
begin
Result := True;
Exit;
end;
end;
Result := False;
end;
{TFieldDataLink Private Methods}
{
If the field exists and can be modified, then
we CanModify as long as this hasn't been set
ReadOnly somewhere else. Do we need any extra tests here?
}
function TFieldDataLink.GetCanModify: Boolean;
begin
if FieldCanModify then
Result := not ReadOnly
else
Result := False;
end;
{
Set the FieldName and then notify the changes though EditingChanged and Reset
Ensure FField is nil if something goes wrong or FieldName is empty
}
procedure TFieldDataLink.SetFieldName(const Value: string);
begin
if FFieldName <> Value then
begin
FFieldName := Value;
UpdateField;
if Active then
begin
EditingChanged;
Reset;
end;
end;
end;
procedure TFieldDataLink.UpdateField;
begin
if Active and (FFieldName <> '') then
FField := DataSet.FieldByName(FFieldName)
else
FField := nil;
end;
{
This function checks if FField is still associated with the dataset
If not update the field
}
procedure TFieldDataLink.ValidateField;
begin
if not (DataSet.FindField(FFieldName) = FField) then
UpdateField;
end;
procedure TFieldDataLink.ResetEditingSource;
begin
FEditingSource := false;
FEditingSourceSet := false;
end;
{TFieldDataLink Protected Methods}
{ Delphi Help ->
Changes to the Active property trigger the ActiveChanged method.
If an OnActiveChange event handler is assigned, ActiveChanged calls
this event handler. If ActiveChanged is triggered by a transition into
an active state, then before calling the event handler, ActiveChanged makes
sure that the Field for this TFieldDataLink is still valid.
<-- Delphi Help
Update the field instance. When not Active field will be set to nil
Call OnActiveChange
}
procedure TFieldDataLink.ActiveChanged;
begin
if FFieldName <> '' then
begin
UpdateField;
EditingChanged;
Reset;
end;
if Assigned(FOnActiveChange) then
FOnActiveChange(Self);
end;
{ Delphi Help ->
Changing the field binding can change the validity of the CanModify
property, since individual field components can disallow edits. If
TFieldDataLink is in an editing state when the Field property is changed,
EditingChanged checks the CanModify property. If CanModify is False, it
changes back out of the editing state.
Note: This differs significantly from the inherited EditingChanged method
of TDataLink. The functionality of the inherited method is replaced in
TFieldDataLink by the OnEditingChange event handler.
<-- Delphi Help
ok so another event... but this time we simply change modified state
if Editing and not CanModify? or do we also change to match if
if not Editing and CanModify? i.e If Editing <> CanModify?? Will assume
the latter just in case. easy to change back if I am wrong.
Also based on this we replace parent routine, so do we need to keep track
of Editing state ourself? I hope this is right. Anyone know for sure?
OK .. based on the Modified routine we need to turn off
our IsModified routine when succesfull right? so for now just turn
it off as per my example.
}
procedure TFieldDataLink.EditingChanged;
var
RealEditState : Boolean;
begin
RealEditState := (CanModify and Inherited Editing);
if (FEditing <> RealEditState) then
begin
FEditing := RealEditState;
if not FEditing then
begin
IsModified := False;
ResetEditingSource;
end;
if Assigned(FOnEditingChange) then
FOnEditingChange(Self);
end;
end;
{ Delphi Help ->
LayoutChanged is called after changes in the layout of one of the
containers of the Control for this TFieldDataLink that might change the
validity of its field binding. For example, if the Control is embedded
within a TCustomDBGrid, and one of the columns is deleted, the Field
property for the Control might become invalid.
<-- Delphi Help
Ensure FField is valid and notify
}
procedure TFieldDataLink.LayoutChanged;
begin
ValidateField;
if FField <> nil then
begin
EditingChanged;
RecordChanged(nil);
end;
end;
{ Delphi Help ->
Applications can not call this protected method. It is triggered
automatically when the contents of the current record change.
RecordChanged calls the OnDataChange event handler if there is one.
TDataLink.RecordChanged:
The Field parameter indicates which field of the current record has changed in value.
If Field is nil (Delphi) or NULL (C++), any number of fields within the current record may have changed.
<-- Delphi Help
Call Reset if AField = FField or aField = nil
}
procedure TFieldDataLink.RecordChanged(aField: TField);
begin
if (aField = nil) or (aField = FField) or
((FField <> nil) and (FField.FieldKind = fkLookup) and IsKeyField(aField)) then
Reset;
end;
{ Delphi Help ->
UpdateData overrides the default UpdateData method to call the
OnUpdateData event handler where the data-aware control can write any
pending edits to the record in the dataset.
<-- Delphi Help
where..can write pending events. So I guess when we have already
called Modified? Aka if not IsModified exit otherwise call event?
works for me.
}
procedure TFieldDataLink.UpdateData;
begin
if not IsModified then
exit;
try
if Assigned(FOnUpdateData) then
FOnUpdateData(Self);
finally
IsModified := False;
end;
end;
{ Delphi Help ->
Call FocusControl to give the Control associated with this TFieldDataLink
object the input focus. FocusControl checks whether the Control can receive
input focus, and if so, calls its SetFocus method to move focus to the
Control.
<-- Delphi Help
Check if the field matches and if Control is TWinControl than call SetFocus
Set the FieldRef to nil so no other control get focus
}
procedure TFieldDataLink.FocusControl(aField: TFieldRef);
var
WinControl: TWinControl;
begin
if Assigned(aField) and (aField^ = FField) and (FControl is TWinControl) then
begin
WinControl := TWinControl(FControl);
if WinControl.CanFocus then
begin
aField^ := nil;
WinControl.SetFocus;
end;
end;
end;
{TFieldDataLink Public Methods}
constructor TFieldDataLink.Create;
begin
inherited Create;
VisualControl := True;
//FField := nil;
//FFieldname := '';
end;
{ Delphi Help ->
Use Edit to try to ensure that the contents of the field can be modified.
A return value of True indicates that the field was already in an editing
state, or that the DataSource was successfully changed to allow editing.
A return value of False indicates that the DataSource could not be changed
to allow editing. For example, if the CanModify property is False, Edit
fails, and returns False.
<-- Delphi Help
ok so the way I see it, since the inherited function calls EditingChanged,
which we have already overriden to modify our own Editing state if its invalid,
I should just be calling the inherited routine here, but only if CanModify,
since there is no point otherwise. But since we _are_ keeping track of editing
state ourselves we return our own state, not the inherited. If anyone know
better please fix.
}
function TFieldDataLink.Edit: Boolean;
var
editingSrc: Boolean;
begin
editingSrc := (not FEditing) and (Dataset<>nil) and not(Dataset.State in dsEditModes);
if (not FEditing) and CanModify then
inherited Edit;
Result := FEditing;
if not FEditingSourceSet then
begin
// should be triggered one time only if editing succeeded
FEditingSource := FEditing and editingSrc;
FEditingSourceSet := true;
end;
end;
{ Delphi Help ->
Call Modified when the Control for this TFieldDataLink begins processing
edits.
<-- Delphi Help
ok so. well _that's_ helpfull. for the moment going to keep track
by adding an IsModified... based on the other functions thus far
we need to know whether we are in state, so I am assuming it goes
Call Modified ->
IsModified:=True;//Waiting for modifications
Call SomeFunction->
If IsModified then begin
(do something)
IsModified := False;//All modifications complete
end
else
(do something else? exit?);
}
procedure TFieldDataLink.Modified;
begin
IsModified := True;
end;
{ Delphi Help ->
The Control that owns a TFieldDataLink object calls its Reset method to
process a UI action that cancels edits to the field. Reset calls the
OnDataChange event handler without writing any pending changes to the
record in the dataset.
<-- Delphi Help
Just call to the OnDataChange Event, and turn off IsModified
}
procedure TFieldDataLink.Reset;
begin
if Assigned(FOnDataChange) then
FOnDataChange(Self);
IsModified := False;
ResetEditingSource;
end;
CONST
DBCBEVENT_CHANGE = 1; // CustomDBCombobox Detected change event
DBCBEVENT_SELECT = 2; // CustomDBCombobox Detected select event
DBCBEVENT_CLOSEUP = 4; // CustomDBCombobox Detected closeup event
DBCBEVENT_WHEEL = 8; // CustomDBCombobox Detected mousewheel event
{$Include dblookup.inc}
{$Include dbedit.inc}
{$Include dbtext.inc}
{$Include customdblistbox.inc}
{$Include dblistbox.inc}
{$Include dblookuplistbox.inc}
{$Include dbradiogroup.inc}
{$Include dbcheckbox.inc}
{$Include customdbcombobox.inc}
{$Include dbcombobox.inc}
{$Include dblookupcombobox.inc}
{$Include dbmemo.inc}
{$Include dbgroupbox.inc}
{$Include dbimage.inc}
{$Include dbcalendar.inc}
{$Include dbcustomnavigator.inc}
initialization
RegisterPropertyToSkip(TField,'Calculated','VCL compatibility property', '');
finalization
FieldClasses.Free;
end.