Falling back to 2.2.6

[Slyde]

I've been working on a personal project that was started with 2.2.4.  When I switched to 2.2.6, nothing broke.  All my code worked as expected.  However, when I installed 3.0.0, I lost a really important aspect of my program. 

It's just a trivia application, where the user selects an answer and then verifies it.  On a wrong answer, the user-selected answer gets a red background and the correct answer lights up green.  That doesn't happen with 3.0.0.  The procedure itself runs flawlessly through all of its code.  But it fails to change the label color.  So I switched back to 2.2.6 and all is well, again.

Lazarus 2.2.6 was a really nice release anyway.  So I'll just stick with it until the bugs are gone from 3.0.0.

[wp]

What is your operating system?

[Slyde]

OS: Linux Mint 21.2

[wp]

I can confirm this on Manjaro. Seems to be a bug for me since the Label is custom-drawn.

But regarding colors there is always an uncertainty depending on the widgetset. Although there is a Color property, its value is often neglected by the widgetset.

Therefore, if colors are important in your application, you simply should draw the text by yourself rather than relying on a component. For example, you could use a TPaintbox instead of a TLabel, and in its OnPaint event you draw the text:

Code: Pascal  [Select][+][-]

1. unit Unit1;
2.  
3. {$mode objfpc}{$H+}
4.  
5. interface
6.  
7. uses
8.   Classes, SysUtils, Forms, Controls, Graphics, Dialogs, ExtCtrls, StdCtrls;
9.  
10. type
11.   TResult = (UndefinedResult, CorrectResult, WrongResult);
12.  
13.   { TForm1 }
14.  
15.   TForm1 = class(TForm)
16.     Button1: TButton;
17.     Button2: TButton;
18.     PaintBox1: TPaintBox;
19.     procedure Button1Click(Sender: TObject);
20.     procedure Button2Click(Sender: TObject);
21.     procedure PaintBox1Paint(Sender: TObject);
22.   private
23.     SavedResult: TResult;
24.     procedure ShowResult(AResult: TResult);
25.  
26.   public
27.  
28.   end;
29.  
30. var
31.   Form1: TForm1;
32.  
33. implementation
34.  
35. {$R *.lfm}
36.  
37. { TForm1 }
38.  
39. procedure TForm1.ShowResult(AResult: TResult);
40. begin
41.   SavedResult := AResult;
42.   Paintbox1.Invalidate;
43. end;
44.  
45. procedure TForm1.PaintBox1Paint(Sender: TObject);
46. const
47.   COLORS: array[TResult] of TColor = (clNone, clGreen, clRed);
48.   MSG: array[TResult] of string = ('', 'Correct', 'Wrong');
49. begin
50.   Paintbox1.Canvas.Font.Color := COLORS[SavedResult];
51.   Paintbox1.Canvas.TextOut(0, 0, MSG[SavedResult]);
52. end;
53.  
54. procedure TForm1.Button1Click(Sender: TObject);
55. begin
56.   ShowResult(CorrectResult);
57. end;
58.  
59. procedure TForm1.Button2Click(Sender: TObject);
60. begin
61.   ShowResult(WrongResult);
62. end;
63.  
64. end.

 

[Slyde]

I appreciate that, wp.  I've never used TPaintBox for anything, but clearly see its upside.  Thanks for the heads-up.

[wp]

Or if you refrain from custom-painting, you could also use ("abuse") a TPanel: it has a Caption, which nicely can be recolored, you can even left/right/top/bottom-align the caption, or center it. Just simply switch the borders off (BevelInner and BevelOuter) and make sure that the panel's ParentColor is true.

I can confirm this on Manjaro.

Very strange: repeating this in Mint, and now in Manjaro again, the label color does change!

[PawelO]

I suppose you have already solved this, but...

https://wiki.lazarus.freepascal.org/Lazarus_3.0_release_notes#TLabel.Transparent.2C_.Color_and_.ParentColor_changes

Set TLabel.Transparent to False and it will be colored.