Question

I’m using Qt 4.3.1 (I’m not able to uptade at the moment) for a program, anyway in Windows dead keys (^, ´, `, …) don’t arrive at the keyPressedEvent(), i always have to press them twice.

So why don’t those dead keys arrive? How can I fix it?

In MacOS everything works fine though.

Thx, eL.

Answer 1

After looking at the Qt documentation I’m not sure if keyPressEvent is supposed to deliver dead keys or not. I’m actually kind of surprised that you see them on a Mac.

I’m guessing that Qt is choosing to wait for WM_CHAR events, or something, before sending the keyPressEvent for your widget. As you can see from this page: http://msdn.microsoft.com/en-us/library/ms646267(VS.85).aspx#_win32_Dead_Character_Messages the order of key events when a user pressed a dead-key followed by a real-key is:

WM_KEYDOWN
WM_DEADCHAR
WM_KEYUP
WM_KEYDOWN
WM_CHAR
WM_KEYUP

If you really want to capture the deadchar key-presses, look at subclassing QApplication and overriding the winEventFilter (http://doc.qt.io/qt-4.8/qcoreapplication.html#winEventFilter) method. This will let you capture the WM_DEADCHAR events as they come in. You can then create a KeyEvent and dispatch it to the widget that currently has focus.