receiver type *** for instance message is a forward declaration

Question

In my iOS5 app, I have NSObject States class, and trying to init it:

states = [states init];

here is init

Answer 1

I was trying to use @class "Myclass.h".

When I changed it to #import "Myclass.h", it worked fine.

Answer 2

You are using

States states;

where as you should use

States *states;

Your init method should be like this

-(id)init {
  if( (self = [super init]) ) {
      pickedGlasses = 0;
  }
  return self;
}

Now finally when you are going to create an object for States class you should do it like this.

State *states = [[States alloc] init];

I am not saying this is the best way of doing this. But it may help you understand the very basic use of initializing objects.

Answer 3

Check if you imported the header files of classes that are throwing this error.