key-value-observing

I have a ViewController creating an instance of a UIView, and then I register an observer with the instance, such that logoAnimation = [[MainLogoAnimation alloc] init]; [logoAnimation addObserver:self forKeyPath:@"patrocinioDidLoad" options:(NSKeyValueObservingOptionNew|NSKeyValueObservingOptionOld) context:nil]; then, in the same file, I have: - (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context { NSLog(@"%@ \n %@ \n %@ \n ",keyPath,object,change); } But, although I have checked and double-checked that logoAnimation

Im trying to find a good way to handle memcache keys for storing, retrieving and updating data to/from the cache layer in a more civilized way. Found this pattern, which looks great, but how do I turn it into a functional part of a PHP application? The Identity Map pattern: http://martinfowler.com/eaaCatalog/identityMap.html Thanks! Update: I have been told about the modified memcache (memcache-tag) that apparently does do a lot of this, but I can't install linux software on my windows development box... Well, memcache use IS an identity map pattern. You check your cache, then you hit your

I am using Core Data to model an entity which has both attributes and relationships. I would like to make one of the attributes dependent on two other relationships. The Core Data FAQ and several other examples use +(NSSet *)keyPathsForValuesAffectingValueForKey:(NSString *)key for this purpose. However, this only seems to be called for all of my relationship properties, but not for any of the attributes. In addition keyPathsForValuesAffecting<key> never gets called for any of my attributes. Is this the normal behaviour or am I missing something? How can I calculate one attribute based on

Do I need to subscribe/unsubscribe to individual elements of an array? I want to update each table view cell individually to reflect changes in the backing array. By changes I mean not append/remove operations but update of the properties of the objects of the array. I hope I was able to explain what I want to achieve. Thanks To use KVO, declare the model object with dynamic properties: class Foo: NSObject { @objc dynamic var bar: String // in Swift 3, `@objc` is not necessary; in Swift 4 we must make this explicit init(bar: String) { self.bar = bar super.init() } } Then, let the cell process

Regarding "Ensuring KVO Compliance", there are some official definition which seem like hard to understand In order to be considered KVO-compliant for a specific property, a class must ensure the following; The class must be key-value coding compliant for the property as specified in Ensuring KVC Compliance. The class must allow automatic observer notifications for the property, or implement manual key-value observing for the property. Who can give more specific examples to make this more clear ? Thanks Benedict Cohen Take a look at Ensuring KVO Compliance the Automatic Versus Manual Support