View Issue Details

IDProjectCategoryView StatusLast Update
0037151LazarusLCLpublic2020-05-30 00:11
Reporterbald zhang Assigned To 
Status newResolutionopen 
PlatformWindows, Linux 
Product Version2.0.8 
Summary0037151: label is shown even under a panel or groupbox
Descriptionrecently upgrade my development environment to 2.0.x, when design some testing app, found this issue.

a label on form, under a panel or a groupbox, it SHOULD hidden but it shown, both design time and run time.
if put a memo, the label was covered.

1.8.4 win32: good
2.0.8 win32: has issue
2.0.8 gtk2-linux: good.
trunk qt5-linux: has issue

haven't check every components.
Steps To Reproduceput a label on form
put a panel(or a groupbox), move the panel over the label, the label is still shown.
TagsNo tags attached.
Fixed in Revision
WidgetsetWin32/Win64, QT5
Attached Files


bald zhang

2020-05-29 00:02


2.0.8-win32-design.png (12,805 bytes)   
2.0.8-win32-design.png (12,805 bytes)   
2.0.8-win32-running.png (12,991 bytes)   
2.0.8-win32-running.png (12,991 bytes)   

Zeljan Rikalo

2020-05-29 10:11

developer   ~0123122

That's because TPanel is transparent by default under qt,qt5 and win32


2020-05-29 10:48

developer   ~0123125

Last edited: 2020-05-29 10:50

View 2 revisions

These are my observations for Win, did not check Linux:

  Turn off ParentBackground of the panel. This is the same behavior as in Delphi.

  By default, The Groupbox is transparent in Delphi like in Lazarus. But in Delphi there is a ParentBackground property again which can be used to make the GroupBox opaque - this is missing in Lazarus. In Lazarus you can achieve opaquness by setting the Groupbox's Color to a value different from clDefault.

bald zhang

2020-05-30 00:08

reporter   ~0123134

Last edited: 2020-05-30 00:11

View 2 revisions

I just looking for something like "Transparent" but didn't notice the ParentBackground property,
and there is nothing about this in wiki..

Make a more detail sample and found Panel.ParentBackground is not working on qt5.
and there is different between design and run time.

on gtk2: label was covered in anyway.
win32-design.png (18,375 bytes)   
win32-design.png (18,375 bytes)   
win32-running.png (16,519 bytes)   
win32-running.png (16,519 bytes)   
qt5-design.png (14,440 bytes)   
qt5-design.png (14,440 bytes)   
qt5-running.png (12,091 bytes)   
qt5-running.png (12,091 bytes)   

Issue History

Date Modified Username Field Change
2020-05-29 00:02 bald zhang New Issue
2020-05-29 00:02 bald zhang File Added: 2.0.8-win32-design.png
2020-05-29 00:02 bald zhang File Added: 2.0.8-win32-running.png
2020-05-29 10:11 Zeljan Rikalo Note Added: 0123122
2020-05-29 10:48 wp Note Added: 0123125
2020-05-29 10:50 wp Note Edited: 0123125 View Revisions
2020-05-30 00:08 bald zhang Note Added: 0123134
2020-05-30 00:08 bald zhang File Added: win32-design.png
2020-05-30 00:08 bald zhang File Added: win32-running.png
2020-05-30 00:08 bald zhang File Added: qt5-design.png
2020-05-30 00:08 bald zhang File Added: qt5-running.png
2020-05-30 00:11 bald zhang Note Edited: 0123134 View Revisions