What is different QKeyEvent modifiers in Qt4 and Qt5

Question

When I enter the number pad side of the keyboard in qt4, I want to receive QEvent::KeyPress and process it. However, if I check the modifiers() of the event, KeypadModifier should come in, but NoModifier is entered in the first time. After that, get a proper KeypadModifier. In qt5, the keypadModifier is obtained from the beginning. Why is it like this?

Answer 1

I found the problem with qt4 itself.

https://bugreports.qt.io/browse/QTBUG-15833?gerritIssueStatus=Open

So, I use KeyRelase event.