[Qt-interest] How can I change a button's background?

[Oliver Demetz]

Hi!
You are trying to reimplemtent a feature which is already available out 
of the box from the lib.
Have a look into StyleSheets, eg
button.setStyleSheet("background-image:url(./img.png);");
Regards,
Oliver


Kermit Mei schrieb:
> Hello community!
> 
> How can I change a button's background? 
> 
> I know I can use styleSheet, but, my problem is that there're so many
> buttons, and every button's background may be change by the users at
> running time, and their background may not be the same. Also, I must
> remember the last background changed by user, and reload them at the
> next running time.
> 
> How Can I do it? I what to use paintEvent() to do it, but when I repaint
> the background, I can't see any different effect when I press the
> buttons. My code is like this: 
> 
> //The Header file:
> #ifndef _REMOTEBUTTON_H
> #define _REMOTEBUTTON_H
> 
> #include <QPushButton>
> #include <QString>
> 
> class QPixmap;
> 
> class RemoteButton : public QPushButton
> {
>   Q_OBJECT
> public:
>   RemoteButton(QWidget *parent = 0);
>   ~RemoteButton();
> 
>   void setBackGround(const QString picFile);
> 
> protected:
>   void paintEvent(QPaintEvent *event);
>   QPixmap *pixmap;
> };
> 
> #endif //_REMOTEBUTTON_H
> 
> 
> //The source file:
> #include <QPen>
> #include <QPainter>
> #include <QLabel>
> #include <QPixmap>
> 
> #include "RemoteButton.h"
> 
> RemoteButton::RemoteButton(QWidget *parent)
>   :QPushButton(parent),pixmap(0)
> {
>   //Do Nothing Here!
> }
> 
> RemoteButton::~RemoteButton() {
>   if(pixmap != 0)
>     delete pixmap;
> }
> 
> void RemoteButton::setBackGround(const QString picFile) {
>   if( pixmap != 0)
>     delete pixmap;
>   pixmap = new QPixmap(picFile);
> }
> 
> void RemoteButton::paintEvent(QPaintEvent *event) {
>   if(pixmap != 0) {
>     QPainter painter(this);
>     painter.drawPixmap(0,0,width(),height(),*pixmap);
>   }else
>     QPushButton::paintEvent(event);
> }
> 
> 
> //The test main.cpp file
> #include <QApplication>
> #include "RemoteButton.h"
> 
> int main(int argc,char *argv[])
> {
>   QApplication app(argc,argv);
>   RemoteButton rBtn;
>   rBtn.setBackGround("./bk.png");
>   rBtn.show();
>   return app.exec();
> }
> 
> 
> It can works, but I can't see and different effects when I press it.
> 
> Hope your help.
> Thanks:)
> 
> Kermit