Round view on "move by background" window

FROM : glenn andreas
DATE : Fri Mar 21 21:52:49 2008

I've got a window that can be moved by clicking on the background 
(it's irregularly shape, so it doesn't have a title bar).  In that 
window is a view which is basically circular (not opaque, only draws 
and responds to a circular area in the middle of the view).  The 
problem is that this results in "dead spots" in the corners of that 
view where I'd expect to be able to drag the window (like I can 
everywhere else in the background).

The view returns NO for -isOpaque, and NO for -mouseDownCanMoveWindow 
(since it needs to be able to track and respond to clicks in the 
content).  In order to handle the fact that the view is non-square, 
I've implemented -hitTest: to see if the mouse is in the circular 
"live" area, and return the view, and return nil for things outside 
that (which results in the super-views hitTest routine to return the 
superview).

I've even overridden the window's content view to determine that it's 
hitTest: properly returns the content view when the user clicks on the 
corner of the round view.

Nothing I've tried, however, allows the user to actually drag the 
window while clicking in the corners of the round view.  It's almost 
as if the "can move window by background" logic goes by bounding boxes 
only and doesn't actually call hitTest to determine what is clicked on 
(to see whose -mouseDownCanMoveWindow it should pay attention to). 
Everywhere else in the window, dragging works exactly as expected (so 
the window's isMovableByWindowBackgound works correctly), but just not 
those four corners.

Short of having the window's content view return NO for its 
mouseDownCanMoveWindow and then add window moving to the mouseDown/
mouseDragged routines (which seems ugly at best), is there something 
I'm missing?


Glenn Andreas                      <email_removed>
  <http://www.gandreas.com/> wicked fun!
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