Posted whenever a portion of a nonretained
NSWindow object is exposed, whether by being ordered in front of other windows or by other windows being removed from in front of it.
- macOS 10.0+
The notification object is the
NSWindow object that has been exposed. The
user dictionary contains the following information:
Key Value The rectangle that has been exposed (an
NSValue object containing an NSRect).
The rectangle that has been exposed (an