Why is my camera (that follows the player) not working (SpriteKit)? - ios

Question

So, in this game I'm making the player can move left and right using the accelerometer and jump by tapping the screen. Now the player must evade enemies frome the sky and climb up by jumping on de fallen enemies. The player should be able to go up infinitely until he dies, therefore a camera is needed to follow the player on his journey up. I have read some other Stack Overflow posts and consulted Apple's programming guide, but I'm not able to figure it out. This is what I added:
-(void) createSceneContents
{
self.world = [SKNode node];
self.playerSize = self.frame.size.width/7;
self.player = [self.playerData newPlayer:self.playerSize];
self.player.name = #"player";
self.player.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:CGSizeMake(self.playerSize-5,self.playerSize-5)];
self.player.physicsBody.allowsRotation = NO;
self.player.physicsBody.categoryBitMask = self.playerCategory;
self.player.physicsBody.contactTestBitMask = self.enemyCategory | self.edgeCategory;
self.isTouchingGround = NO;
self.player.position = CGPointMake(CGRectGetMidX(self.frame), 100);
[self.playerData movementSetup];
[self addChild:self.world];
[self.world addChild:self.player];
}
There are more things in this method, but those aren't important for this question.
-(void) didSimulatePhysics
{
self.world.position = CGPointMake(-(self.player.position.x-(self.size.width/2)), -(self.player.position.y-(self.size.height/2)));
}
Then there are a lot of other methods adding other things to the game including enemies, collision handeling etc.
Ok, so when I did this the player movement suddenly stopped working, the players spawn position was changed and the rest of the sprites, that weren't child nodes of world, just kept on going.
Why isn't this working, how can I fix it, and how does it work?

Answer 1

In order to make a camera follow your player add these simple lines of code:
int cameraEdge = 100;
if (self.player.position.y > cameraEdge) {
worldPosition.y = cameraEdge - self.player.position.y;
}
self.world.position = worldPosition;
What this does: Whenever your player's y-position is higher than 100 (or whatever you set it to) the world's position starts following the player. I've tested it and it works perfectly