Question

I am having a problem figuring out how to simply return an integer from a method.

Here is what I have:

simple.h

@interface simple : NSObject {
}
- (int)simpleMethod;
@end

simple.m

#import "simple.h"
@implementation simple
- (int)simpleMethod {
    return 0;
}
@end

simpleViewController.m

- (IBAction)simpleButtonPressed:(id)sender {
    int test = [simple simpleMethod];
}

I am getting a warning on the line “int test…” that says, “simple may not respond to ‘+simpleMethod'”. And another warning that says, “Initialization makes integer from pointer without cast”.

My program is crashing on this line, so although this is just a warning it seems to be a problem.

I want to be able to use “simpleMethod” without creating an instance of the class “simple”. Is this possible?

Problem fixed: changed the – to a + as per Peter’s suggestion.

Answer 1

Currently you have simpleMethod defined as an instance method. But to do what you want to do, you need to define the method as a class method:

@interface simple : NSObject {
}
+ (int)simpleMethod;
@end

#import "simple.h"
@implementation simple
+ (int)simpleMethod {
    return 0;
}
@end

- (IBAction)simpleButtonPressed:(id)sender {
    int test = [simple simpleMethod];
}

Note the “+” on the method definition

Also the typo(?) where you had the class definition of queryDatabase, but the class implementation of simple