How to create a button exit for app

[m4u_hoahoctro]

How to create a button with function: When press it, program will close ( button for form)
thanks

[Blaazen]

If it is a main form then simply put there a button and its OnClick method:

Code: [Select]

procedure TForm1.Button1Click(Sender: TObject);
begin
  Close;
end;
should be enough.

[marcov]

Won't that only close that form?

Application.terminate;

seems to be safer

[howardpc]

Closing the main form terminates the Application (as Blaazen stated). Of course closing any secondary form merely closes that window without affecting the rest of the process.

[Redenegue]

I have found that neither of these will work on a form that is minimized and borderless. Once minimized, you need to restore the program with the Windows icon. Then using a main menu exit either close or terminate the program. The program minimizes, it does not close. I have just started looking for a solution. This was my first stop.

[lucamar]

I've just tested and it works here (Laz 1.8.4/Linux 32 bit).
The only times a Form.Close doesn't also close the application are

• when it's not the Application.MainForm;
• when one sets a handler for the form's OnClose event and changes CloseAction; or
• when one sets a handler for the form's OnCloseQuery event and sets CanClose to False.

These last two, of course, don't close the form either ...

[J-G]

I have found that neither of these will work on a form that is minimized and borderless. Once minimized, you need to restore the program with the Windows icon. Then using a main menu exit either close or terminate the program. The program minimizes, it does not close. I have just started looking for a solution. This was my first stop.

????   Surely, if the program is minimised there are no buttons visible !

[Zoran]

I have found that neither of these will work on a form that is minimized and borderless.

I understand you are able to click that button on the minimized form when you claim it does not work.
Well, not that I can test it, but I would expect it to work. Of course, you still have to click on that button.

[Thaddy]

If it is a main form then simply put there a button and its OnClick method:

Code: [Select]

procedure TForm1.Button1Click(Sender: TObject);
begin
  Close;
end;
should be enough.

No. Closes the form.
Application terminate. As Marco pointed out.

[munair]

If it's the main form, Close() terminates the application (my experience).

[Zoran]

If it's the main form, Close() terminates the application (my experience).

Everyone's experience, since always. And documented.

Thaddy, why don't you try it before posting?

Closing the main form terminates the application.
So Close should be enough after all. Unless, as Lucamar pointed out, OnClose or OnCloseQuery do not intercept it and change this behaviour.

[Raj Gupta]

If it is a main form then simply put there a button and its OnClick method:

Code: [Select]

procedure TForm1.Button1Click(Sender: TObject);
begin
  Close;
end;
should be enough.

Its work for me to.
This is the correct method.
I have used it.

[trev]

Yes, I know, this is an ancient thread but, while researching a similar issue, I discovered Redenegue was correct despite some poking fun at him. He mentioned Windows and my example is macOS when the one and only Form window is not the active one (eg it is occluded by another or it is minimised).

Code: Pascal  [Select][+][-]

1. unit Unit1;
2. {$mode objfpc}{$H+}
3.  
4. interface
5.  
6. uses
7.   Forms, StdCtrls, CocoaAll;
8.  
9. type
10.   TForm1 = class(TForm)
11.     Button1: TButton;
12.     procedure Button1Click(Sender: TObject);
13.     procedure FormClose(Sender: TObject; var CloseAction: TCloseAction);
14.   end;
15.  
16. var
17.   Form1: TForm1;
18.  
19. implementation
20.  
21. {$R *.lfm}
22.  
23. procedure TForm1.Button1Click(Sender: TObject);
24. begin
25.   NSLog(NSStr('closing'));
26.   //System.Exit;            // works
27.   Application.Terminate;    // works
28.   //Form1.Close; // results in abnormal program termination eventually after bouncing
29.                  // back and forth between FormClose and Button1Click many times
30. end;
31.  
32. procedure TForm1.FormClose(Sender: TObject; var CloseAction: TCloseAction);
33. begin
34.   NSLog(NSStr('leaving...'));
35.   Application.BringToFront; // needed
36.   Button1.Click;
37. end;
38.  
39. end.

And to explain how to exit while minimised or occluded, one right clicks on the macOS dock application icon and chooses the Quit option, similar to Windows where one would right click on the item in the task bar and choose Close.

[lucamar]

The button click should just call Close (for the form) which, if it's the main form, will close the application. That will in turn fire the OnClose event: if you re-Click the button there you are caught in an infinite loop, so don't do that.

When the application is closed externally (e.g. by the methods you cite), the OnClose event will be fired, just as if you had called Close, so there is no need (or shouldn't be) to call the button's OnClick handler.

[trev]

When the application is closed externally (e.g. by the methods you cite), the OnClose event will be fired, just as if you had called Close, so there is no need (or shouldn't be) to call the button's OnClick handler.

In fact it does terminate if I wait long enough (long enough being about 10 seconds). Not really the user experience one would want though and I'd missed it because I had not been waiting that long.