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What is the difference between self.myVariable = obj; and myVariable = obj;, when I use @propery/@synthesize to create `myVariable?
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The self variable is used to represent the instance of the class which is often used in object-oriented programming. It works as a reference to the object. Python uses the self parameter to refer to instance attributes and methods of the class.
self is only a reference to the current instance within the method. You can't change your instance by setting self .
However, it's not required with a static method. Because, the static methods are self sufficient functions and they can't access any of the class variables or functions directly. Let's look at a complete example with self and cls variables and a static method without any arguments.
Self is the first argument to be passed in Constructor and Instance Method. Self must be provided as a First parameter to the Instance method and constructor. If you don't provide it, it will cause an error.
It's important to note that dot-syntax is converted to a simple objc_msgSend call by the compiler: that is to say that underneath it acts exactly like a message send to the accessor for that variable. As such, all three of the following are equivalent:
self.myVariable = obj;
[self setMyVariable:obj];
objc_msgSend(self, @selector(setMyVariable:), obj);
Of course, this means that using dot-syntax actually results in a full message send, meaning calling a new function and all the overhead that is associated with it. In contrast, using simple assignment (myVariable = obj;) incurs none of this overhead, but of course it can only be used within the instance methods of the class in question.
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