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Re: KVO and the observeValueForKeyPath bottleneck

Hi Matt,
Yeah I'm actually doing something similar though I wasn't aware of NSSelectorFromString.

For a custom view that responds to a few dozen attributes of the controller's current selection....

- (void)observeValueForKeyPath:(NSString *)keyPath
ofObject:(id)object
change:(NSDictionary *)change
context:(void *)context
{
NSString *keyPathName;
if ([keyPath isEqualToString:@"selection.bgImage.color"] == YES){
// handle special case of this attribute of a relationship
keyPathName = @"bgImageColor";
} else {
// convert "selection.attribute" keypath to appropriate accessor name -- by abusing pathExtension method :)
keyPathName = [keyPath pathExtension];
}
[self setValue:[object valueForKeyPath:keyPath] forKey:keyPathName];
}

So observing "selection.attribute" will call my setAttribute accessor with the new value via KVC.

Possibly not the most proper setup, but it seems to work well enough for this view's situation.

George

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 >KVO and the observeValueForKeyPath bottleneck (From: Matt Neuburg <email@hidden>)



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