Question

I made a class in objective-c and I made an instance in another class my code looks like this…

    #pragma mark - HelloWorldLayer

    @interface HelloWorldLayer()
    -(void) initPhysics;
    @end

    @implementation HelloWorldLayer

    -(id) init
    {
        if( (self=[super init])) {

            // init physics
            [self initPhysics];

            //THE CLASS I'M HAVING TROUBLE WITH
            id player;

            player = [Blob new];

            //SAYS SET NODES CAN'T BE FOUND
            [player setNodes];

            [self scheduleUpdate];
        }
        return self;
    }

    -(void) initPhysics
    {
        //BLAHBLAHBLAH
    }

    -(void) draw
    {
        //BLAHBLAHBLAH
    }

    -(void) update: (ccTime) dt
    {
        //BLAHBLAHBLAH
    }

    - (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
    {
        //BLAHBLAHBLAH

    }

    @end

    #pragma mark - HelloWorldLayer

    @interface Blob()
    -(void) setNodes;
    @end

    @implementation Blob

   -(void) setNodes;
    {
        b2BodyDef bodyDef;
        b2Body *body;

        bodyDef.type = b2_dynamicBody;

        bodyDef.position.Set(100/PTM_RATIO,100/PTM_RATIO);

        body = world->CreateBody(&bodyDef);

        // Define another box shape for our dynamic body.
        b2CircleShape circle;
        circle.m_radius = 32/PTM_RATIO;

        // Define the dynamic body fixture.
        b2FixtureDef fixtureDef;
        fixtureDef.shape = &circle; 
        fixtureDef.density = 0.5f;
        fixtureDef.friction = 0.5f;
        fixtureDef.restitution = 0.0f;
        body->CreateFixture(&fixtureDef);

    }

    @end

I am coding a game with cocos2d and box2d for the iphone and I took out most of the bulk code. But I am having a problem with the blob class. I create an instance named player and try to call the function “setNodes” And my problem is every time I compile it gives me a warning that setNodes cant be found… I feel like I did something wrong because I know it’s there… Objective-c is skrewwy I’m a C++ man, thankyou 🙂

Answer 1

setNodes should be declared before the line:

[player setNodes];

You probably should declare your classes in an .h file and import it, like you do in C++.

Or at least, put the declaration of Blob before the implementation of HelloWorldLayer

@interface Blob()
    -(void) setNodes;
@end

@implementation HelloWorldLayer
// ...