I am having a Q3ButtonGroup with some QPushButton.

I want to update the text of the button when it is being clicked.
Hence I used setText() to perform what I want.
However I found that the setText() doesn't update the ui.
I mean, when I use text() to cout the text of the button, I found that the new text is actually already be set, but in the user interface, I found that it doesn't update at all!!!!
I tried to call all those thing like update()/repaint() after calling the setText but it still doesn't work.

Can anyone tell me what's going on?
Thanks!