Ken, so far you could cmopletely delete the component-code you have written. Just replace the lines in wmLButtonDown/Up by inherited; and then do the special processing you may need. Just make sure to set ControlStyle appropriately.
Best wishes, Gunnar Gunnar Blumert Software-Entwicklung Waldstraße 117 D-25712 Burg Germany Tel. +49-(0)4825-2892 Fax +49-(0)4825-1217 Email [EMAIL PROTECTED] http://www.blumert.de ----- Original Message ----- From: "Ken Phipps" <[EMAIL PROTECTED]> To: "Borland's Delphi Discussion List" <[email protected]> Sent: Thursday, August 18, 2005 10:48 AM Subject: TGraphicControl Mouse Event Problem > I'm trying to create a simple component to draw rows/columns of > buttons. The first thing I'm trying to get done is the mouse event > handling. I was able to figure out how to catch the windows messages > and have them trigger published events from some examples I've found, > but I'm having a problem it. If you click very quickly in rapid > succession, the control seems to steal the mouse input for the entire > application. You can't even click on the form's close button as the > click gets taken. > > In a test project, I notice that in a listbox that displays the > events when they are fired, when it shows a MouseUp event firing > without a corresponding MouseDown, that's when the control will begin > to steal all mouse input from that point onward. You have to kill the > app at that point. I read a post through a Google search about > problems like this happening with TGraphicControl descendants, so I > tried changing it to a TCustomPanel, but the problem is still there. > > Can anyone tell me what is causing this and how I can fix it? > > Here's a stripped down version of the component code with only the > relevant parts: > > unit MyButtonPanel; > > interface > > uses > Types, Classes, Messages, Controls, Graphics, ExtCtrls; > > type > > TMouseDownEvent = procedure(Sender: TObject; Button: TMouseButton; > Shift: TShiftState; X, Y: Integer) of object; > TMouseUpEvent = procedure(Sender: TObject; Button: TMouseButton; > Shift: TShiftState; X, Y: Integer) of object; > TMouseClickEvent = procedure(Sender: TObject; Btn: Integer) of > object; > > TMyButtonPanel = class(TGraphicControl) > private > FOnMouseDown: TMouseDownEvent; > FOnMouseUp: TMouseUpEvent; > FOnMouseClick: TMouseClickEvent; > protected > procedure WM_LBUTTONDOWN(var Msg: TWMLButtonDown); Message > WM_LBUTTONDOWN; > procedure WM_LBUTTONUP(var Msg: TWMLButtonUp); message > WM_LBUTTONUP; > public > constructor Create(AOwner: TComponent); override; > destructor Destroy; override; > published > property OnMouseClick: TMouseClickEvent read FOnMouseClick write > FOnMouseClick; > property OnMouseDown: TMouseDownEvent read FOnMouseDown write > FOnMouseDown; > property OnMouseUp: TMouseUpEvent read FOnMouseUp write > FOnMouseUp; > end; > > procedure Register; > > implementation > > uses > Forms, Consts, SysUtils, CommCtrl, Themes, Dialogs; > > Constructor TMyButtonPanel.Create(AOwner: TComponent); > begin > inherited Create(AOwner); > end; > > Destructor TMyButtonPanel.Destroy; > begin > inherited destroy; > end; > > procedure TMyButtonPanel.WM_LBUTTONDOWN(Var Msg: TWMLButtonDown); > begin > if Assigned(FOnMouseDown) then FOnMouseDown(Self, mbLeft, > KeysToShiftState(Msg.Keys), Msg.XPos, Msg.YPos); > if Assigned(FOnMouseClick) then FOnMouseClick(Self, 0); > end; > > procedure TMyButtonPanel.WM_LBUTTONUP(Var Msg: TWMLButtonDown); > begin > if Assigned(FOnMouseUp) then FOnMouseUp(Self, mbLeft, > KeysToShiftState(Msg.Keys), Msg.XPos, Msg.YPos); > end; > > procedure Register; > begin > RegisterComponents('Samples', [TMyButtonPanel]); > end; > > end. > > -------------------------------------------- > Events in Test Project: > > procedure TMain.MyButtonPanel1MouseClick(Sender: TObject; Btn: > Integer); > begin > ListBox1.Items.Add( IntToStr(Btn) ); > end; > > procedure TMain.MyButtonPanel1MouseDown(Sender: TObject; > Button: TMouseButton; Shift: TShiftState; X, Y: Integer); > begin > ListBox1.Items.Add('MouseDown'); > end; > > procedure TMain.MyButtonPanel1MouseUp(Sender: TObject; > Button: TMouseButton; Shift: TShiftState; X, Y: Integer); > begin > ListBox1.Items.Add('MouseUp'); > end; > --------------------------------------------- > _______________________________________________ > Delphi mailing list -> [email protected] > http://www.elists.org/mailman/listinfo/delphi _______________________________________________ Delphi mailing list -> [email protected] http://www.elists.org/mailman/listinfo/delphi
