@AnkurSharma
But, I also expect that when I am resetting the attribute of WA_InputMethodEvent my widget should no more get the input method events anymore, and thats how it works on Qt on OSX.
I don't know how it works on OSX, I can say for sure though that QObject::eventFilter is executed before the QObject::event method (this is documented) and since you're not giving Qt leeway to process the event as it ordinarily would in the overriden QWidget::event method (you stop the event propagation when you return true from the event filter) you shouldn't expect it to respect the widget attribute. That's what I'm claiming. You should move your code from the eventFilter method to a QWidget::inputMethodEvent override.
