Re: Easier way to make NSView subclasses refresh on a property change?
Re: Easier way to make NSView subclasses refresh on a property change?
- Subject: Re: Easier way to make NSView subclasses refresh on a property change?
- From: Lee Ann Rucker <email@hidden>
- Date: Thu, 04 Feb 2016 00:33:22 +0000
- Thread-topic: Easier way to make NSView subclasses refresh on a property change?
[self addObserver:self forKeyPaths:[Foo keyPathsThatAffectDisplay] ...context:SomeUniquePtrValue];
(We have a class addition to NSObject to take an array of keyPaths and lopp through addObserver:forKeyPath: etc, because we use multiple key paths *everywhere*)
- (void)observeValueForKeyPath: ...
{
if (context == SomeUniquePtrValue && [ [Foo keyPathsThatAffectDisplay] containsObject:keyPath])
[self setNeedsDisplay:YES];
etc
}
> On Feb 2, 2016, at 10:05 PM, Graham Cox <email@hidden> wrote:
>
> Hi all,
>
> Whenever I make a custom view class, it often has a bunch of properties that affect the content it renders. So, for each setter that does this, I have to override the setter, do whatever it normally does plus call -setNeedsDisplay:YES.
>
> This gets tedious.
>
> Is there a good way to automate this for a given set of properties? I considered overriding -didChangeValueForKey: and checking the key against a set of exported property names, and that would work, except all my custom views would then need to subclass this one special kind of view instead of NSView. Can it be done with a standard NSView? (MacOS)
>
> A similar requirement applies to CALayer too.
>
> —Graham
>
>
>
> _______________________________________________
>
> 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
_______________________________________________
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