Click-through window

[ultr]

If anyone needs the same effect on X11, here is the code:

#include <QX11Info>
#include <X11/Xlib.h>
#include <X11/extensions/shape.h>
 
MyWidget::MyWidget() : QWidget()
{
  QRegion region;
  XShapeCombineRegion( QX11Info::display(), winId(), ShapeInput, 0, 0, region.handle(), ShapeSet );
}

#include <QX11Info>
#include <X11/Xlib.h>
#include <X11/extensions/shape.h>

MyWidget::MyWidget() : QWidget()
{
  QRegion region;
  XShapeCombineRegion( QX11Info::display(), winId(), ShapeInput, 0, 0, region.handle(), ShapeSet );
}

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You need link X11 extensions library. You may add this to your .pro file:
LIBS += -lXext

Note that window's decoration will still be clickable, so you will probably have to get rid of it.

[mattie]

window masks are different from the OP's question, see http://doc.qt.io/qt-5/qwidget.html#setMask-1
when you click within the region, the event is not passed on to the underlying window