How to tell if a user is _currently_ mouse-selecting text in QPlainTextEdit?

[Drew W]

I can get the cursor and check hasSelection(), but this only tells me if there is text selected. Not whether the user is currently in the process of selecting something. I would like something that evaluates to currentlySelecting:

hasSelection = false
currentlySelecting = false
// user holds mouse button
hasSelection = false
currentlySelecting = false
// user drags mouse to select text
hasSelection = true
currentlySelecting = true
// user releases mouse
hasSelection = true
currentlySelecting = false

I tried hooking into mousePressEvent/mouseReleaseEvent for the QPlainTextEdit, but mouseReleaseEvent doesn't get fired when another app takes focus and then the mouse is released, leaving me in a bad state. Is there a more reliable way to check whether the user is currently mouse-selecting text in a QPlainTextEdit?

[jsulm]

@Drew-W Maybe https://doc.qt.io/qt-5/qwidget.html#leaveEvent could help in the case other app gets focus?