Re: NSArrayController subclass computed property not being updated
Re: NSArrayController subclass computed property not being updated
- Subject: Re: NSArrayController subclass computed property not being updated
- From: Mike Abdullah <email@hidden>
- Date: Wed, 29 Jul 2009 18:55:55 +0100
On 29 Jul 2009, at 06:09, Alexander Heinz wrote:
Hello all,
I've got an NSArrayController subclass with a computed property:
@property (readonly) BOOL canRemoveSelection;
(This basically adds some application-specific checks to the
canRemove: property, so that I can bind a "remove" button in
Interface Builder.)
I want the property to be recomputed every time the "selectionIndex"
or "selectionIndexes" of the array controller change, so, in my ".m"
file, I have:
+ (NSSet*)keyPathsForValuesAffectingCanRemoveSelection
{
return [NSSet setWithObjects:@"selectionIndex",
@"selectionIndexes", nil];
}
(I realize this is probably redundant, but bear with me.)
However, the accessor for the property (i.e., "- (BOOL)
canRemoveSelection") is never called, beyond the initial call when
the object is created. As a result, the button bound to the property
never changes state.
I've checked to make sure that -setSelectionIndexes: is being
called, and it is, but the property is not re-computed.
Does anyone see anything immediately wrong here?
Further to the other suggestions, have you checked in the debugger
that your -keyPathsForValuesAffectingCanRemoveSelection is being
called? It might be that NSArrayController overrides -
keyPathsForValuesAffectingKey: to not call custom methods like yours.
Mike.
_______________________________________________
Cocoa-dev mailing list (email@hidden)
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:
This email sent to email@hidden