self.view.window 只是当前view的window,可能是keywindow
@property(nonatomic, readonly) UIWindow *window
Description
The receiver’s window object, or nil if it has none. (read-only)
This property is nil if the view has not yet been added to a window.
[[UIApplication sharedApplication] keyWindow]
@property(nonatomic, readonly) UIWindow *keyWindow
This property holds the UIWindow object in the windows array that is most recently sent the makeKeyAndVisible message.
[[UIApplication sharedApplication] windows]
@property(nonatomic, readonly) NSArray *windows
This property returns an array of the application's visible and hidden windows. The windows are ordered back to front.
Saya rasa UIView.window mengembalikan tetingkap tempat paparan semasa berada, tidak semestinya tetingkap kunci
Jika paparan ialah kawasan tertentu pada papan kekunci, view.window ialah tetingkap papan kekunci.
Tidak semestinya.
Boleh dinilai melalui view.window.keyWindow.