Qt 4.7.4 QPropertyAnimation not working - c++

Question

I'm trying to have animation on a button click event. But somehow the animation is not working. I have referred the Qt reference docs, but could not find the root cause which is causing the issue
Below is sample code :
void MainWindow::AnimationClick()
{
// define toolbar y movement positions for animation
TOOLBAR_Y_SHOWN = 0;
TOOLBAR_Y_HIDDEN = -m_AnimatedWidget->height();
m_AnimatedWidget = new AnimatedWidget(this);
QPropertyAnimation *m_ani = new QPropertyAnimation(m_AnimatedWidget, "pos", this);
m_ani->setDuration(500);
m_ani->setEndValue(QPoint(m_AnimatedWidget->pos().x(), TOOLBAR_Y_HIDDEN));
m_ani->setEasingCurve(QEasingCurve::InBack);
m_ani->start();
}
With the above implementation nothing is happening on the click event.
Any suggestions , Thanks.

Answer 1

This looks wrong:
TOOLBAR_Y_HIDDEN = -m_AnimatedWidget->height();
m_AnimatedWidget = new AnimatedWidget(this);
First you access m_AnimatedWidget then you allocate it?
When you get a crash, such as segmentation fault, always run your program in a debugger. It would have helped you find this error quite easy as it would have stopped on the line of the error.

Answer 2

m_ani->setDuration(500);
setDuration() argument is expressed in milliseconds. You should probably put more than half a second when you are testing.

Answer 3

I got it. I was not allowing the m_AnimatedWidget to show upon the screen.
Below is the edited snippet.
void MainWindow::AnimationClick()
{
// define toolbar y movement positions for animation
TOOLBAR_Y_SHOWN = 0;
m_AnimatedWidget = new AnimatedWidget(this);
TOOLBAR_Y_HIDDEN = -m_AnimatedWidget->height();
QPropertyAnimation *m_ani = new QPropertyAnimation(m_AnimatedWidget, "pos", this);
m_ani->setDuration(5000);
m_ani->setEndValue(QPoint(m_AnimatedWidget->pos().x(), TOOLBAR_Y_HIDDEN));
m_ani->setEasingCurve(QEasingCurve::InBack);
m_ani->start();
m_AnimatedWidget->show();
}