ios,cocoa,reactive-cocoa , Reactive Cocoa: subscribe only to new values
Reactive Cocoa: subscribe only to new values
Question:
Tag: ios,cocoa,reactive-cocoa
I'm new to Reactive Cocoa. What I'm trying to achieve is get notified every time property value changes. However, I don't want to get notified when property is set to the same value. Here's some code:
self.testProperty = 0;
[[RACObserve(self, self.testProperty) skip:1] subscribeNext:^(id x) {
NSLog(@"Did Change: %@", x);
}];
self.testProperty = 1;
self.testProperty = 1;
self.testProperty = 1;
self.testProperty = 1;
self.testProperty = 1;
And this is what I get on console's output
> Did Change: 1
> Did Change: 1
> Did Change: 1
> Did Change: 1
> Did Change: 1
I expected that "Did change" would be printed only once, not five. Is there any way to subscribe only to new values?
Answer:
There is a method for that, distinctUntilChanged:
[[[RACObserve(self, self.testProperty)
skip:1]
distinctUntilChanged]
subscribeNext:^(id x) {
NSLog(@"Did Change: %@", x);
}];
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