could not explain with simple words, in what situations are Synthesize? I understand it, it makes it possible to referred via GET and SET-. It turns out that properi without synthesis does not differ from the class variable? And then does it even make sense to write proputations without Synthesize?

Answer 1, Authority 100%

Property (Property) appeared in Objective-C only in version 2.0 and they are reduced to conventional methods (or messages, if any). That is if you declare the property

@ property (nonatomic, retain) nsstring * property1;

In fact, you are declared such a getter and setter:

- (nsstring *) property1;
- (void) setProperty1: (nsstring *) value;

When you use the property

nsstring * p = v.property1;
v.Property1 = P;

In fact, the compiler “unfolds” is in such a code:

nsstring * p = [v property1];
[v setProperty1: p];

The @synthesize property1; operator is deployed in the code definition for the setter and the getter (in accordance with the parameters that you specified in the property declaration).
You can not write @synthesize , but in this case you will have to write the realization of the getter and setter yourself. If you do not make any other, the compiler will give a warning, and the code that uses the property will take out.

Since @Property Develops in Setter and Getter, it needs to be written in the class interface (usually in the header file – .h). Similarly, @synthesize “generates” Setter and Getter implementations, so used in the implementation file (.m, .mm).

Answer 2, Authority 24%

From the question “Objective-C is @synthesize Required or Optional? “:

No We Don’t Need To Do That As of Xcode 4.4, Which Added A Feature Called Default Synthesis Of Properties.

Simply Put, It Generates This Automatically:

@ synthesize name = _name;

In short, you can not steam: Starting with Xcode 4.4, IDE itself default sets @synthesize name = _name; Wherever it is required.