How to change cursor to Qt.ForbiddenCursor while drag hover over a qlistwidget?

Leon Zhang

How to change the cursor icon to ForbiddenCursor while user drag item and hover mouse over a qlistwidget?
I have tried:

def dragEnterEvent(self, event):
        if event.mimeData().hasFormat('text/plain'):
            self.setCursor(qt.Qt.ForbiddenCursor)
            event.ignore()
        else:
            event.accept()
            qt.QListWidget.dragEnterEvent(self, event)

but above code won't work while holding mouse left button down, setCursor works only after I release mouse left button.

Thanks in advance.

SGaist

Hi,

You have to implement the drag enter and move events method and there not accept the proposed action.

Leon Zhang

@SGaist Thanks, could you give a code example here?
I have tried following:

def mouseMoveEvent(self, event):
        if event.mimeData().hasFormat('text/plain'):
             event.ignore()

But the event in mouseMoveEvent does not have mimeData member method.

JonB

@Leon-Zhang
QDragMoveEvent, not QMouseMoveEvent.

SGaist

Not the mouse event handlers, the drag related event handlers.

QWidget::dragEnterEvent
QWidget::dragMoveEvent

Leon Zhang

@SGaist @JonB
Thanks.
I have another issue: I have an override of mouseMoveEvent function, and seems
dragMoveEvent won't be called if mouseMoveEvent override presents.

Any idea how to fix this? Thanks.

JonB

@Leon-Zhang
That does not sound right, you having an override should not be relevant. Unless, at a guess, your override fails to call the base implementation, and that prevents the drag move event ever getting raised...?

Leon Zhang

@JonB I have tried to remove dragEnterEvent override, and dragMoveEvent and mouseMoveEvent both been triggered now. Wired.

JonB

@Leon-Zhang
I don't know what you're up to, but so far as I recall and as @SGaist said you will need to override both dragEnterEvent and dragMoveEvent to alter the cursor during a drag successfully.

Leon Zhang

@JonB It seems async lock process affected the implementation of dragMoveEvent override, remove this lock solved the problem.