[SOLVED] TButton.OnMouseUp does not trigger

[ling]

I bind an event to OnMouseUp for TButton, but when the button be clicked, only OnMouseDown and OnClick be triggered, is it a bug?

Lazarus version: 2.0.6
FPC: 3.0.4
macOS Catalina 10.15.7

[lucamar]

If you have properly set up events then yes, it looks like a bug, though it might be OS-specific behaviour; I don't know enough about Macos to even guess.

The "normal" chain of events is:

• MouseDown,
• MouseUp,
• Click

[Handoko]

It works on my Ubuntu Mate 20.10 Lazarus 2.0.10 GTK2.

I wrote a very simple demo to test it. Download and run my code, if it does not work on your computer, please report it to the bugtracker: https://bugs.freepascal.org/view_all_bug_page.php?project_id=1

Code: Pascal  [Select][+][-]

1. unit Unit1;
2.  
3. {$mode objfpc}{$H+}
4.  
5. interface
6.  
7. uses
8.   Classes, SysUtils, Forms, Controls, Graphics, Dialogs, StdCtrls;
9.  
10. type
11.  
12.   { TForm1 }
13.  
14.   TForm1 = class(TForm)
15.     Button1: TButton;
16.     procedure Button1MouseDown(Sender: TObject; Button: TMouseButton;
17.       Shift: TShiftState; X, Y: Integer);
18.     procedure Button1MouseUp(Sender: TObject; Button: TMouseButton;
19.       Shift: TShiftState; X, Y: Integer);
20.   end;
21.  
22. var
23.   Form1: TForm1;
24.  
25. implementation
26.  
27. {$R *.lfm}
28.  
29. { TForm1 }
30.  
31. procedure TForm1.Button1MouseDown(Sender: TObject; Button: TMouseButton;
32.   Shift: TShiftState; X, Y: Integer);
33. begin
34.   Button1.Caption := 'MouseDown event triggered';
35. end;
36.  
37. procedure TForm1.Button1MouseUp(Sender: TObject; Button: TMouseButton;
38.   Shift: TShiftState; X, Y: Integer);
39. begin
40.   Button1.Caption := 'MouseUp event triggered';
41. end;
42.  
43. end.

[ling]

@Handoko Thanks for your demo code. I've tried it, mouse up doesn't trigger.

[trev]

It works in macOS 10.14 with Lazarus trunk and FPC 3.0.4 or 3.2.0 or trunk.

Looks like it was fixed in Lazarus 2.0.8 - the OP needs to upgrade! See Bug #38099.

I just confirmed that it works in Lazarus 2.0.10 with FPC 3.2.0.

[ling]

@trev Thanks,

I updated lazarus and fpc to the latest version, it works fine now.