Accessing multiple instances of one Object in Objective C

Question

I think what you are asking for is something like this:

//
//  C4WorkSpace.m
//  Week_4_Assignment
//
//  Created by Parth Soni on 2013-10-06.
//

#import "C4Workspace.h"

@implementation C4WorkSpace
{
    C4Shape *circ; // the shapes I am building
    CGRect mycirc, obstacle_circ;
    CGPoint p, o; // the coordinates of those shapes
    C4Sample *sample;
    int glcounter[3];
    BOOL collisionHasHappened ;
    C4Timer *timer;
    NSMutableArray * myobstacles;
}

//Setting up the game!

-(void)setup {
    collisionHasHappened = FALSE; //Checks if objects have collided
    [self createShape]; //Creates the Userball

    sample = [C4Sample sampleNamed:@"Jump.wav"]; // Audio files
    [sample prepareToPlay]; // Load the audio


    myobstacles = [NSMutableArray array];
    for ( int i = 0; i < 3; i++)
    {
        C4Shape * s = [C4Shape ellipse: mycirc];
        o.x += 200;
        o.y += 300;
        s.center =  o; // The Center of the Circle is P
        [myobstacles addObject:s];
        [self.canvas addShape:myobstacles[i]]; // Add THY CIRCLE
        glcounter[i]=0;
    }
}

// Creating Userball

-(void) createShape {

    mycirc = CGRectMake(0,0, 100,100); // The Size of the Original Circle
    p = self.canvas.center; // CG Point
    circ = [C4Shape ellipse: mycirc]; // It's a Circle!
    circ.center =  p; // The Center of the Circle is P
    [self.canvas addShape:circ]; // Add THY CIRCLE
    circ.userInteractionEnabled = NO; // Thy circle has no sense of any interaction thing

}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *place = [[event allTouches] anyObject]; // Get touches
    CGPoint location = [place locationInView:place.view]; // Gets the location of the current mouse point
    p.x = location.x-10;
    p.y =location.y-10;
    circ.animationDuration = 0.1f;
    circ.center =  p; // The Center of the Circle is P
    if (!collisionHasHappened){
        [self checkForCollision];
    }
}

-(void) checkForCollision {

    for ( int i = 0 ; i < 3; i++)
    {
        C4Shape * s = myobstacles[i];
        if(CGRectIntersectsRect(circ.frame, s.frame ))
        {
            CGFloat time = 1.0f; // just make a random time frame!!!
            s.animationDuration = time; // make that the duration now!
            NSInteger r = [C4Math randomIntBetweenA:75 andB:100]; // How farm from the radius does this need to be?
            CGFloat theta = DegreesToRadians([C4Math randomInt:360]); // randomizing on which degree will the circle appear.

            s.center = CGPointMake(r*[C4Math cos:theta] + (300/2),
                                            r*[C4Math sin:theta] + (700/2));
            [sample play];
            glcounter[i]++;
            [self checkGameCompletion];

            collisionHasHappened = TRUE;

            timer = [C4Timer automaticTimerWithInterval:2.0f target:self method:@"collisionActivate" repeats:NO];
        }

    }
}

-(void) collisionActivate {
    collisionHasHappened = FALSE;

}

-(void) checkGameCompletion {

    if (glcounter[0] == 3 && glcounter[1] ==1 && glcounter[2] ==2 ){
        C4Log(@"GAME COMPLETE");
    }
}

@end

What I have done is made a NSMutableArray to hold the instances of the C4Shape for your obstacles. I have also added an int array to hold glcounter. Now what happens is that a for loop creates a new C4Shape and then adds it to the array. In your checkForCollision function you will now find another for loop that iterates over the array and checks each object to see if it collides.

When you have a number of objects that you want to interact with it is best to think about putting them into an array. You can then create a new pointer to the object you want to talk to at the time you want to talk to it. This is one of the real strengths of Objective-C.