Panning a QImage using translate
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I wanted a basic image viewer with zoom and pan. Initially i tried with frame and by using scroll area and flabel resize,
But my requirements have changed so i wanted to keep my frame size same with no scroll area.simply and fixed size frame and zoom and pan in itMy label properties are set as
label->setscaledcontents(false);
label->resize(800,800);
lbel->setsizepolicy(ignored;ignored);I was able to zoom using image->scaled();
now i was trying to pan by using mouse move event,so i am writing my mouse move event
void mouseMoveEvent(QMouseEvent *event)
{
if(pan){
QTransform trans;
trans=trans.translate(10.2,10.2);
*image=image->transformed(trans);
displayimage();m_panStartX = event->x();
m_panStartY = event->y();
event->accept();
return;
}m_panStartX = event->x();
m_panStartY = event->y();
event->ignore();
}
But the image is not getting panned.Any solutions? -
Hi,
Please use code tags '@@' while posting your code.
Have you subclassed the label ? and there reimplemented mouseMoveEvent ? Normally QTransform is used in paintEvent.
When you do transform operations like scale,translate etc.. you need to do "setTransform":http://qt-project.org/doc/qt-5/qpainter.html#setTransform in paintEvent so that transformations take effect. Can you provide more details ?
