I have a program somewhat similar to Microsoft Paint, and I'm working on implementing canvas resizing. I need to detect if the mouse cursor has moved into resizing range, and if the left mouse button is held down while the mouse is being moved. I have a QGraphicsRectItem set up as my canvas, and I want to detect mouse movement and mouse button state in my QGraphicsRectItem, without it being selected.
I've been using QGraphicsItem.hoverMoveEvent for detecting if the cursor is within resizing range or not, but when the left mouse button is held down, hoverMoveEvent is no longer triggered.
There's mouseMoveEvent, but as the docs say:
If you do receive this event, you can be certain that this item also received a mouse press event, and that this item is the current mouse grabber.
In my program, it's impractical for my canvas to be the current mouse grabber when resizing. I may have other objects that need to retain their selection states while the canvas is being resized.
I realize I could do this in the QGraphicsScene containing my QGraphicsRectitem, but to avoid interdependence between them, I'd like to be able to do this all in my QGraphicsRectItem.
So my question is: How, if possible, do I detect mouse movement and mouse button states on a QGraphicsRectitem without the it being selected?