Confusion with header and Implementation files in Objective-C

First off, please forgive the stupidness of this question but Im not from a C/C++ background. I'm a little unclear about what the difference in roles between the .h and .m files when it comes to properties.

I understand the concept of interfaces, and I see that in part the .h file is an interface for the implementation, but what I am not clear on is this:

Why are properties/methods defined outside of the {} braces?
What am i defining in the braces when I write something like this:

IBOutlet UITextField *numberField;

Is this a field definition in an interface?
When I am adding the @Property lines to the .h files are these actual implementations of a n auto property or just an interface blueprint? If so is the @syntesis the actual implementation?

I guess my biggest confusion seems to be that if I want a property I'm defining what I need in three different places (1) in the interfaces braces, (2) as @property outside the braces and (3) with @synthesis in the .m file. This seems long winded, but its fine if I can work out what these three parts do.

Cheers, Chris.

iphone objective-c properties

Edit Report

Well that is just Objective C syntax, methods and @property outside {} and variables inside {}.
@property is the way of telling that you are going to write getter and setters (kind of enforcing it), but you can write getter/setter without setting them @property. @property is in .h file because its declaration. And why it is outside {}, well as i said before its just the syntax, what we can do?
@synthesis will in actual implement getter and setters, if you dont synthesis but you have set them @property, you have to implement those getter and setters by your hand. And @synthesis is in .m file because its implementation.

Something more for you to read on this subject can be find here.

http://theocacao.com/document.page/510

answered 2009-09-19T23:16:23.480

Confusion with header and Implementation files in Objective-C

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