TPageControl and nboShowCloseButtons?

[Avishai]

In TPageControl under "Options" there is "nboShowCloseButtons" and there is "OnCloseTabClicked" Event .  I set "nboShowCloseButtons:= True" but I do not see a CloseButton.  I also can not trigger "OnCloseTabClicked" Event.  What am I missing?

[Blaazen]

Here - Lazarus 0.9.31 r31122M FPC 2.5.1 x86_64-linux-qt - works.
See screenshot. Maybe you have old version of Lazarus or your platform is not supported or other reason.
OnCloseTabClicked event is fired but tab is not closed. Probably it must be done by programmer. But I don't know how because event has only parameter Sender: TObject.

[fabienwang]

nboShowCloseButtons affects GTK2 and QT widgetsets.
It does nothing on Windows widgetset as windows cannot do it natively

[Avishai]

Thanks guys.  I think that is a first for me.  Usually I am told "that only works in Windows"   Now I find something that doesn't work in Windows.

[Dibo]

By the way: Some time ago I looked for CSV kompoent and I found this screenshot:
http://wiki.lazarus.freepascal.org/Image:Example.png
This is windows and page control have close buttons. Is it just fpGUI? Anyone know?

[fabienwang]

no Dibo, theses are linux screenshots with a vista theme. And the closes buttons are into gedit (nothing related to lazarus unfortunately)

[Avishai]

NotePad++ has close buttons on the Tabs in Windows.  I wonder how they did it.  I will see if I can find out.  If I find anything, I will post it.

[Sora-Kun]

Hi,
  Notepad++ is made in C++, as i can see from the source code.
However, you can have the [X] button on the tabsheets, when you build your application using the Qt LCLWidget, it's done by going to Project -> Project Options -> Build Mode, and change the Macro Value of LCLWidgetType to Qt.
However, there is a small bug, when you have 2 tabsheets, when you press the [X] button of the non-active page, the active one will close.
However, you must code the close action by your self. Lazarus wont do it for you.

Sincerely,
LinkOS.

[mcsquirrel]

Hi,

I just stumbled here, having the same problem on Windows when coding a cross-platform application. However, I've chosen to stay with the default LCLWidgetType and (as a workaround or additional feature) allow to close tabs on mouse middle-click.

Therefor, you just need to react to the OnMouseUp event of the TPageControl and find out which tab has been clicked:

Code: Pascal  [Select][+][-]

1. procedure TForm1.PageControl1MouseUp(Sender: TObject; Button: TMouseButton;
2.   Shift: TShiftState; X, Y: Integer);
3. var
4.   p: TPOINT;
5.   i: Integer;
6. begin
7.   // Close tab on middle click
8.   if Button = mbMiddle then begin
9.     p.x := X;
10.     p.y := Y;
11.     i := PageControl1.TabIndexAtClientPos(p);
12.     if i = -1 then exit;
13.     PageControl1.Pages[i].Free;
14.   end;
15. end;
16.  

Works like a charm!
Manuel

PS: Initially, I had tried sending a TCM_HITTEST message along with a TTCHitTestInfo structure containing the mouse coordinates to Windows (as suggested in some Delphi forums), but somehow always got -1 as a result in Lazarus. Thus I found the TabIndexAtClientPos function within Lazarus sources which does essentially the same, but seems to work on any platform - just tested on Windows and Mac