On Mar 25, 2013, at 12:47 PM, Chris Tracewell <ch...@thinkcl.com> wrote:
> I have a subclass of NSOutlineView that has custom delegate methods. In the
> implementation file I get an error for "No known instance method for
> selector..." when I call these declared methods using [self delegate] or
> delegate. However the compiler suggested using _delegate and that makes the
> error go away. I thought since my subclass inherits from NSOutlineView that
> delegate would be recognized and available.
"[self delegate]" is not the same as "delegate" - the former sends the
-delegate message, the latter references a variable named "delegate" (which the
compiler is telling you does not exist).
> -(void)keyDown:(NSEvent *)theEvent
> {
> if ([[theEvent characters] length] == 0)
> {
> // dead key
> return;
> }
> else if ([[theEvent characters] length] == 1 && [[theEvent characters]
> characterAtIndex:0] == NSEnterCharacter && [[self delegate]
> respondsToSelector:@selector(outlineView: enterKeyPressedForRow:)])
> {
> [delegate outlineView:self enterKeyPressedForRow:[self
> selectedRow]];
For example, here you correctly use "[self delegate]" in the if() condition but
improperly fall back to merely "delegate" for actually dispatching your
delegate message.
> Is _delegate the correct usage here or have I done something else wrong?
> Thank you.
The correct usage is [self delegate] in place of just "delegate." You could
also create a local variable assigned to [self delegate] if you wish.
-Conrad
_______________________________________________
Cocoa-dev mailing list (Cocoa-dev@lists.apple.com)
Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com
Help/Unsubscribe/Update your Subscription:
https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com
This email sent to arch...@mail-archive.com
