MKColorWell+Bindings.m

//
//  MKColorWell+Bindings.m
//  MKPopoverColorWell
//
//  via http://www.tomdalling.com/blog/cocoa/implementing-your-own-cocoa-bindings
//

#import "MKColorWell+Bindings.h"

@implementation MKColorWell (Bindings)
-(void)propagateValue:(id)value
           forBinding:(NSString*)binding;
{
	NSParameterAssert(binding != nil);
    
	// WARNING: bindingInfo contains NSNull, so it must be accounted for
	NSDictionary* bindingInfo = [self infoForBinding:binding];
	if (!bindingInfo)
		return; // there is no binding
    
	// apply the value transformer, if one has been set
	NSDictionary* bindingOptions = [bindingInfo objectForKey:NSOptionsKey];
	if (bindingOptions) {
		NSValueTransformer* transformer = [bindingOptions valueForKey:NSValueTransformerBindingOption];
		if (!transformer || (id)transformer == [NSNull null]) {
			NSString* transformerName = [bindingOptions valueForKey:NSValueTransformerNameBindingOption];
			if(transformerName && (id)transformerName != [NSNull null]){
				transformer = [NSValueTransformer valueTransformerForName:transformerName];
			}
		}
        
		if (transformer && (id)transformer != [NSNull null]) {
			if ([[transformer class] allowsReverseTransformation]) {
				value = [transformer reverseTransformedValue:value];
			} else {
				NSLog(@"WARNING: binding \"%@\" has value transformer, but it doesn't allow reverse transformations in %s", binding, __PRETTY_FUNCTION__);
			}
		}
	}
    
	id boundObject = [bindingInfo objectForKey:NSObservedObjectKey];
	if (!boundObject || boundObject == [NSNull null]) {
		NSLog(@"ERROR: NSObservedObjectKey was nil for binding \"%@\" in %s", binding, __PRETTY_FUNCTION__);
		return;
	}
    
	NSString* boundKeyPath = [bindingInfo objectForKey:NSObservedKeyPathKey];
	if (!boundKeyPath || (id)boundKeyPath == [NSNull null]) {
		NSLog(@"ERROR: NSObservedKeyPathKey was nil for binding \"%@\" in %s", binding, __PRETTY_FUNCTION__);
		return;
	}

    id boundValue = [boundObject valueForKeyPath:boundKeyPath];
    if ([boundValue isNotEqualTo:value] || (nil == boundValue && value))
        [boundObject setValue:value forKeyPath:boundKeyPath];
}
@end