Implicit declaration of function is invalid in C99 iphone app

Question

There are many topics like this but haven't find any which could help me.

my .h file:

-(void) function;

my .m file:

-(void) function {
   /*some basic switch statement for showing images in imageview*/
}

- (IBAction)do_the_function_button:(id)sender {
    function();
}

Where is the mistake? I'm sure it's something very trivial.

It is. Please read a basic Objective-C tutorial. – Oct 09 '13 at 18:35 — , Oct 09 '13 at 18:35

score 5 · Accepted Answer · edited May 23 '17 at 11:46

5

You created a method, which should be called like this [self function];, NOT function();, which is how you call a function.

There is lots of info about the differences between methods and functions floating around, here is one random post I found for instance:

objective c difference between functions and methods

edited May 23 '17 at 11:46

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answered Oct 09 '13 at 18:04

Dima

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Implicit declaration of function is invalid in C99 iphone app

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