Virtual keyboard example

Hi, I want to create very simple virtual keyboard but I don't know how I can do it...

Please give me some example...

I have QWidget with few QPushButtons, when I will push the button I want to send text from this button to
QlineEdit in other widget.

Thank You for any suggestions and examples
Cheers

QKeyEvent, QApplication::postEvent(), QApplication::focusWidget().

Cheers,
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