Trying to remove a sprite during intersection of the object and character in sprite kit

Question

Good afternoon, using Xcode / Spritekit / OSX 10.9.1

I am set up 3 methods to call upon hearts in a tutorial I was trying to expand upon. The hearts are displayed on the scene as follows:

-(SKSpriteNode*) healthContainer1 {

    SKSpriteNode *heart1 = [SKSpriteNode spriteNodeWithImageNamed:@"heartfull"];
    heart1.name = @"healthContainer1";
    heart1.position = CGPointMake(CGRectGetMinX(self.frame) + 25, CGRectGetMaxY(self.frame) - 30);

    return heart1;

    if (hitCount == 3) {

        [self removeFromParent];

    }

}

-(SKSpriteNode*) healthContainer2 {

    SKSpriteNode *heart2 = [SKSpriteNode spriteNodeWithImageNamed:@"heartfull"];
    heart2.name = @"healthContainer2";
    heart2.position = CGPointMake(CGRectGetMinX(self.frame) + 50, CGRectGetMaxY(self.frame) - 30);

    return heart2;

    if (hitCount == 2) {

        [self removeFromParent];
    }

}

-(SKSpriteNode*) healthContainer3 {

   SKSpriteNode *heart3 = [SKSpriteNode spriteNodeWithImageNamed:@"heartfull"];
   heart3.name = @"healthContainer3";
   heart3.position = CGPointMake(CGRectGetMinX(self.frame) + 75, CGRectGetMaxY(self.frame) - 30);

   return heart3;

   if (hitCount == 1) {

       [self removeFromParent];

   }

}

The heart containers are called in the initWithSize: method by

[self addChild:[self heartContainer1]];
[self addChild:[self heartContainer2]];
[self addChild:[self heartContainer3]];

My hitCount is an int set up in the header file and I use the following method along with the 2nd posted part of the update method to detect damage. I am trying to get the heartContainer to remove itself when damage is done based on the hitCount int.

-(void) doDamage:(SKSpriteNode*)character {

    isDamaged = YES;

    hitCount ++;

}

if ( [character intersectsNode:node] && isDamaged == NO) {

    [self doDamage:character];
    NSLog(@"Intersection occured");

}

Sorry if it is excess code displayed on the multiple heartContainer methods, I was just thinking I could check the int in the heartContainer method itself then remove it if the condition was met. I also tried putting the if statements in the initWithSize: method right after calling them and this did not work either.

Answer 1

A couple of things...

1) The following code will never be executed because it follows a return statement that is always executed:

if (hitCount == 1) {
    [self removeFromParent];
}

Same thing goes for the equivalent code in the other two methods... You may as well just remove this dead code.

2) You may want to consider using the hidden property of the nodes to show/hide them, rather than actually adding and removing them from the scene. Using this property has the advantage that you can set the hidden property to NO twice, and the node will just remain hidden. If you call removeFromParent twice on a node, your application will crash.

3) To answer your question, one approach is to modify the doDamage: method so that it shows/hides the right number of health containers. In order to do that, you'll need a way of referencing the health containers, either by keeping references to them or by using the name property. I'd normally do something along these lines:

- (void)doDamage:(SKSpriteNode*)character {
    isDamaged = YES;
    hitCount++;
    [self syncHealthContainers];
}

- (void)syncHealthContainers {
    for(int i = 0; i < [healthContainers count]; ++i)
        healthContainers[i].hidden >= (hitCount > ([healthContainers count] - i));
}