cannot change the QWidget background image.

qtpi

Hey fellas, I've tried to change the background image of a QWidget, so I simply subclass-ed QWidget, and call this->setStyleSheet("QWidget {background-image: url(c:/mybackground.png) }"); in the initializaiton function. it seems nothing has happened.

But then I found out accidentally that if I deleted the declaration of Macro Q_OBJECT in the declaration of the class, the background will be actually replaced by the desired image. But I need this Macro in a normal QApplication.

how could it happen? is there any possibility to change the background image via the "this pointer"?

thnx in advance!

mrjj

hi
You dont need to subclass QWidget to set stylesheet
ui->somewidget->setStyleSheet will do 100% the same
as
this->setStyleSheet inside a subclass.

What is wrong is most likely the path "c:/"
You are pointing to c:. not sure it will load it.
Normally you would add a qresource file
using
New->Qt->Qt resource file
To that new file via right click and Add existing file you add your bg image.
then syntax is then
background-image: url(:/bg.png);
( with rest as is.) notice the ":/"

please see this sample
https://www.dropbox.com/s/d06k4tpmwgapajc/bg.zip?dl=0

right click the widget to see the stylesheet. There is menu when in
Designer.

qtpi

@mrjj hey, thnx for the reply. not familiar with qt designer though, i'll have a look.

mrjj

@qtpi
Well I hope your version have the StyleSheet editor. very handy for
crafting stylesheets and see the effect at once.

qtpi

@mrjj said:

hi I tried to add qt source file. oddly enough the same thing happened, once I deleted the Q_OBJECT Macro, the background will be set correctly, if this Macro is declared the background will not be changed.

I'll try the qt designer afterwards. I'll give a feed back afterwards.

mrjj

@qtpi said:

Q_OBJECT

You will most likely want this so i hope the qrc works for you.