Hiding the window caption
lazarus / 32-Linux

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MarkMLl · 2023-02-23 18:25

This code suffices to toggle the display of the application caption

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i     'z':
begin           case BorderStyle of             bsSizeable:
BorderStyle := bsNone           otherwise             BorderStyle :=
bsSizeable           end;           testCard(true)         end; 
but only works reliably for Qt/Qt5 (i.e. not GTK2/GTK3).

Does anybody have anything better?

MarkMLl

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Blaazen · 2023-02-23 20:08

It seems I found GTk2 hack: set Constraints.MinHeight and
Constraints.MinWidth to something (in OI or in code).

GTk2 probably sets Width and Height to zero somewhere during the
switching the BorderStyle.

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MarkMLl · 2023-02-24 08:08

Is that using the contsraint of the form, or getting at the caption in
some way?

Trying that using code below (Laz 2.2.4, FPC 3.2.2) using GTK2 on KDE
hides/unhides the entire window.

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i     'z':
begin           with Constraints do begin             MinWidth := 0; 
          MinHeight := 0           end;           case BorderStyle of 
           bsSizeable: BorderStyle := bsNone           otherwise     
      BorderStyle := bsSizeable           end;         
 testCard(true)         end; 
Added detail: what I'm doing isn't entirely cosmetic, since it makes
sure that space on the physical display being calibrated isn't
occupied by the caption. I can work around the problem by using Qt5 as
the widget set, although that does mean that I can't run it on the old
laptop I was hoping to use... I've got a slightly rickety optical
bench setup and there's a big advantage to being able to keep the
video generation well separated from the computer I'm sitting at.

MarkMLl

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zeljko · 2023-02-24 11:18

From Qt world: When changing windowFlags (that's border etc) you
should hide(), set new windowflags, show(). Try that with gtk2, x11
philosophy should be same.

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MarkMLl · 2023-02-24 12:07

With GTK2, the entire form/window appears to be being hidden (I didn't
remember that behaviour, but I've upgraded the distro since writing
this and there was a point-level libgtk upgrade).

It's the same irrespective of the presence or hide/show (I've stuck
the form name in there to be absolutely unambiguous), of the
constraint change, or of the APM I added for good measure.

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i     'z':
beginForm1.Hide;{           with Constraints do begin           
 MinWidth := 0;             MinHeight := 0           end; }         
 case BorderStyle of             bsSizeable: BorderStyle := bsNone   
      otherwise             BorderStyle := bsSizeable         
 end;Form1.Show;Application.ProcessMessages;           testCard(true) 
       end; 
Everything else works fine: testcard() basically paints a bullseye
with rings at adjustable positions.

I wonder whether there's any overlap here with people who've used
circular output which presumably didn't have a caption?

In any event, Qt5 works and I suspect I might have to live with that.

MarkMLl

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Blaazen · 2023-02-24 15:14

Why you tried zeros?
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i   with
Constraints do begin             MinWidth := 0;             MinHeight
:= 0           end;I meant non-zero. But I tested it by setting
constraints in OI.

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MarkMLl · 2023-02-24 17:07

The reason I put it in code was that I've also been testing this on
GTK1 (for the Hell of it, and because the laptop I'm using to derive
the device still has a usable copy of a suitably-old Lazarus/FPC) and
it saves putting anything which might be unsupported in the .lfm.

Anyway, the result with the minimum values set to 1 was definitely
interesting: either with or without the hide/show and APM the first z
caused the caption to disappear and the second brought it back (yay!).
However the third z hid the entire form, the fourth brought it back
and so on.

MarkMLl

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MarkMLl · 2023-02-24 18:08

I'm tacking a "published" version of the project on as a zipfile, in
case anybody wants to play with it. However I'd emphasise that this is
for the sake of interest only, and that I am definitely not stuck
because of this.

I've set it to talk to stdin/out rather than Telnet and believe it's
complete, but there might be minor directory issues.

MarkMLl