Re: yearly NSDraggingInfo -draggedImage question (BEWARE!)

FROM : Nathan Vander Wilt
DATE : Thu Mar 20 23:15:35 2008

[sending to the list this time, I might maybe someday eventually get 
used to the reply-to policy here.]
On Mar 20, 2008, at 3:00 PM, Sherm Pendley wrote:
>
> On Thu, Mar 20, 2008 at 5:19 PM, Nathan Vander Wilt <<email_removed>
> > wrote:
> I implemented a dragging destination, and only get nil from [sender
> draggedImage]. Why?
>
> My car wouldn't start this morning. Why not?


Probably the aliens! :-)

If a more detailed explanation would help:


I subclassed an NSImageView to turn it into a dropbox to help me 
prototype a file-opening feature.

I implemented the following method in my DropBox class:

- (NSDragOperation)draggingEntered:(id<NSDraggingInfo>)sender {
   printf("Dragged Image: %x\n", (NSUInteger)[sender draggedImage]);
   return NSDragOperationLink;
}

When I hover any file/folder from the Finder over this drop box, I get:
Dragged Image: 0
in the debugging console. Likewise if I check it in my prepare/
performDragOperation, this value is always nil.

The documentation says nothing about this method ever returning nil, 
so it's even more suprising to me that it would *always* return nil. I 
would expect it to give back a reference to the file/folder icon image 
that I'm dragging around underneath the cursor. Is that not what this 
method is documented to do?

thanks,
-natevw