end;
{ TVDBGridInplaceEdit }
{ TVDBGridInplaceEdit adds support for a button on the in-place editor,
which can be used to drop down a table-based lookup list, a stringlist-based
pick list, or (if button style is esEllipsis) fire the grid event
OnEditButtonClick. }
type
TEditStyle = (esSimple, esEllipsis, esPickList, esDataList);
TPopupListbox = class;
TVDBGridInplaceEdit = class(TInplaceEdit)
private
FButtonWidth: Integer;
FDataList: TDBLookupListBox;
FPickList: TPopupListbox;
FActiveList: TWinControl;
FLookupSource: TDatasource;
FEditStyle: TEditStyle;
FListVisible: Boolean;
FTracking: Boolean;
FPressed: Boolean;
procedure ListMouseUp(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
procedure SetEditStyle(Value: TEditStyle);
procedure StopTracking;
procedure TrackButton(X,Y: Integer);
procedure CMCancelMode(var Message: TCMCancelMode); message CM_CancelMode;
procedure WMCancelMode(var Message: TMessage); message WM_CancelMode;
procedure WMKillFocus(var Message: TMessage); message WM_KillFocus;
procedure WMLButtonDblClk(var Message: TWMLButtonDblClk); message wm_LButtonDblClk;
procedure WMPaint(var Message: TWMPaint); message wm_Paint;
procedure WMSetCursor(var Message: TWMSetCursor); message WM_SetCursor;
protected
procedure BoundsChanged; override;
procedure CloseUp(Accept: Boolean);
procedure DoDropDownKeys(var Key: Word; Shift: TShiftState);
procedure DropDown;
procedure KeyDown(var Key: Word; Shift: TShiftState); override;
procedure MouseDown(Button: TMouseButton; Shift: TShiftState;
X, Y: Integer); override;
procedure MouseMove(Shift: TShiftState; X, Y: Integer); override;
procedure MouseUp(Button: TMouseButton; Shift: TShiftState;
X, Y: Integer); override;
procedure PaintWindow(DC: HDC); override;
procedure UpdateContents; override;
procedure WndProc(var Message: TMessage); override;
property EditStyle: TEditStyle read FEditStyle write SetEditStyle;
property ActiveList: TWinControl read FActiveList write FActiveList;
property DataList: TDBLookupListBox read FDataList;
property PickList: TPopupListbox read FPickList;
public
constructor Create(Owner: TComponent); override;
end;
{ TPopupListbox }
TPopupListbox = class(TCustomListbox)
private
FSearchText: String;
FSearchTickCount: Longint;
protected
procedure CreateParams(var Params: TCreateParams); override;
procedure CreateWnd; override;
procedure KeyPress(var Key: Char); override;
procedure MouseUp(Button: TMouseButton; Shift: TShiftState; X, Y: Integer); override;
end;
procedure TPopupListBox.CreateParams(var Params: TCreateParams);
begin
inherited CreateParams(Params);
with Params do
begin
Style := Style or WS_BORDER;
ExStyle := WS_EX_TOOLWINDOW or WS_EX_TOPMOST;
WindowClass.Style := CS_SAVEBITS;
end;
end;
procedure TPopupListbox.CreateWnd;
begin
inherited CreateWnd;
Windows.SetParent(Handle, 0);
CallWindowProc(DefWndProc, Handle, wm_SetFocus, 0, 0);
end;
procedure TPopupListbox.Keypress(var Key: Char);
var
TickCount: Integer;
begin
case Key of
#8, #27: FSearchText := '''''''';
#32..#255:
begin
TickCount := GetTickCount;
if TickCount - FSearchTickCount > 2000 then FSearchText := '''''''';
FSearchTickCount := TickCount;
if Length(FSearchText) < 32 then FSearchText := FSearchText Key;
SendMessage(Handle, LB_SelectString, WORD(-1), Longint(PChar(FSearchText)));
Key := #0;
end;
end;
inherited Keypress(Key);
end;
procedure TPopupListbox.MouseUp(Button: TMouseButton; Shift: TShiftState;
X, Y: Integer);
begin
inherited MouseUp(Button, Shift, X, Y);
TVDBGridInPlaceEdit(Owner).CloseUp((X >= 0) and (Y >= 0) and
(X < Width) and (Y < Height));
end;
constructor TVDBGridInplaceEdit.Create(Owner: TComponent);
begin
inherited Create(Owner);
FLookupSource := TDataSource.Create(Self);
FButtonWidth := GetSystemMetrics(SM_CXVSCROLL);
FEditStyle := esSimple;
end;
procedure TVDBGridInplaceEdit.BoundsChanged;
var
R: TRect;
begin
SetRect(R, 2, 2, Width - 2, Height);
if FEditStyle <> esSimple then Dec(R.Right, FButtonWidth);
SendMessage(Handle, EM_SETRECTNP, 0, LongInt(@R));
SendMessage(Handle, EM_SCROLLCARET, 0, 0);
if SysLocale.Fareast then
SetImeCompositionWindow(Font, R.Left, R.Top);
end;
procedure TVDBGridInplaceEdit.CloseUp(Accept: Boolean);
var
MasterField: TField;
ListValue: Variant;
begin
if FListVisible then
begin
if GetCapture <> 0 then SendMessage(GetCapture, WM_CANCELMODE, 0, 0);
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