Question

Now with the release of the new Xcode it has been said that properties get synthesized automatically, and indeed they are accessible without synthesizing as long as you use the '_' prefix. But I recently found out that Xcode allows me to access those properties in another way – using a 'self.*' prefix (where the * is the name of the property).

Is this correct? Should I use it? Could it harm my code?

Thanks you.

Answer 1

With _yourProperty you access the instance variable, with self.yourProperty its getter/setter. As long you are sure you have no costumized getter/setter, both is the same (with a very small performance penalty for getter/setter). However, in general, you should use the getter/setter approach (except in getter/setter themself) in case you will change your code later.

EDIT:

@Vanthel: The underline is pure convention. Without @synthesize (or with @synthesize foo), the compiler generates for a property foo a variable _foo. However, by @synthesize foo = my_bar you assign the variable my_bar to be accessed by the accessors of foo.