In WPF, under what circumstances does Visual.PointFromScreen throw InvalidOperationException?

Question

Suppose I wanted to do this, so I can find the current position of the mouse relative to a Visual, without needing access to a specific mouse event:

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Answer 1

There's a static method PresentationSource.FromVisual which:

Returns the source in which a provided Visual is presented.

I know this doesn't solve the underlying problem, but you could check that the Visual is connected to a PresentationSource before calling PointFromScreen. It would prevent the exception, but you'd need to do some more investigation as to why it wasn't connected in the first place.