GTK3: BitBtn+glyph patch

[d4eva]

Hi,
Here's the patch for GTK3 BitBtn, which makes attached Glyph to behave the same as on GTK2/QT5.
I have zero experience with GTK2/GTK3 so I asked copilot to fix the code and it did
Tested on Ubuntu 25.10 (wayland) and BitBtn with a glyph and spacing property looks exactly as I expected it to look.

Code: Pascal  [Select][+][-]

1. diff --git a/lcl/interfaces/gtk3/gtk3widgets.pas b/lcl/interfaces/gtk3/gtk3widgets.pas
2. index bec6a95b4f..6bda7e7aad 100644
3. --- a/lcl/interfaces/gtk3/gtk3widgets.pas
4. +++ b/lcl/interfaces/gtk3/gtk3widgets.pas
5. @@ -10847,26 +10847,50 @@ end;
6.  
7.  procedure TGtk3Button.SetSpacing(AValue: Integer);
8.  var
9. -  ATGValue: TGValue;
10. -  AImage: PGtkWidget;
11. +  Img: PGtkWidget;
12. +  Pos: TGtkPositionType;
13. +  MarginTop, MarginBottom, MarginLeft, MarginRight: Integer;
14.  begin
15. -  // if FSpacing=AValue then Exit;
16. -  FSpacing:=AValue;
17. +  // Normalize spacing
18.    if AValue < 0 then
19. -    FSpacing := 2;
20. -  ATGValue.g_type := G_TYPE_INT;
21. -  ATGValue.set_int(AValue);
22. +    AValue := 0;
23.  
24. -  // no way under gtk3 ... we cannot set style property image-spacing
25. -  // so we are using cheat
26. -  AImage := PGtkButton(FWidget)^.get_image;
27. -  if AImage <> nil then
28. -  begin
29. -    if AValue < 0 then
30. -      AVAlue := 0;
31. -    //TODO: margin depends on layout ! This is ok for left (default) layout
32. -    PGtkImage(AImage)^.set_margin_right(AValue);
33. +  FSpacing := AValue;
34. +
35. +  // Get the image widget
36. +  Img := PGtkButton(FWidget)^.get_image;
37. +  if Img = nil then
38. +    Exit;
39. +
40. +  // Get current image position
41. +  Pos := PGtkButton(FWidget)^.get_image_position;
42. +
43. +  // Reset all margins first
44. +  MarginTop := 0;
45. +  MarginBottom := 0;
46. +  MarginLeft := 0;
47. +  MarginRight := 0;
48. +
49. +  // Apply spacing depending on position
50. +  case Pos of
51. +    GTK_POS_LEFT:
52. +      MarginRight := AValue;
53. +
54. +    GTK_POS_RIGHT:
55. +      MarginLeft := AValue;
56. +
57. +    GTK_POS_TOP:
58. +      MarginBottom := AValue;
59. +
60. +    GTK_POS_BOTTOM:
61. +      MarginTop := AValue;
62.    end;
63. +
64. +  // Apply margins
65. +  PGtkWidget(Img)^.set_margin_top(MarginTop);
66. +  PGtkWidget(Img)^.set_margin_bottom(MarginBottom);
67. +  PGtkWidget(Img)^.set_margin_left(MarginLeft);
68. +  PGtkWidget(Img)^.set_margin_right(MarginRight);
69.  end;
70.  
71.  procedure TGtk3Button.SetImage(AImage: TBitmap);
72.