How to set animated icon to QPushButton in Qt5?

QPushButton can have icon, but I need to set animated icon to it. How to do this? I created new class implemented from QPushButton but how to replace icon from QIcon to QMovie?

Solution

Since I had to solve this problem for a project of mine today, I just wanted to drop the solution I found for future people, because this question has lots of views and I considered the solution quite elegant. The solution was posted here. It sets the icon of the pushButton every time, the frame of the QMovie changes:

auto movie = new QMovie(this);
movie->setFileName(":/sample.gif");
connect(movie, &QMovie::frameChanged, [=]{
  pushButton->setIcon(movie->currentPixmap());
});
movie->start();

This also has the advantage, that the icon will not appear, until the QMovie was started. Here is also the python solution, I derived for my project:

#'hide' the icon on the pushButton
pushButton.setIcon(QIcon())
animated_spinner = QtGui.QMovie(":/icons/images/loader.gif")
animated_spinner.frameChanged.connect(updateSpinnerAniamation)           

def updateSpinnerAniamation(self):
  #'hide' the text of the button
  pushButton.setText("")
  pushButton.setIcon(QtGui.QIcon(animated_spinner.currentPixmap()))

Once you want to show the spinner, just start the QMovie:

animated_spinner.start()

If the spinner should disappear again, then stop the animation and 'hide' the spinner again. Once the animation is stopped, the frameChanged slot won't update the button anymore.

animated_spinner.stop()
pushButton.setIcon(QtGui.QIcon())