Creating and using an Array of objects in Objective-C

April 4, 2009

First we need an array to hold the objects (in this case bullets)

NSMutableArray *myBullets = [[NSMutableArray alloc] init];  Create and then add the objects

for (int i=0; i<5; i++){ 
	//create Bullet 
	*newBullet = [[Bullet alloc] init]; 
  //add to the array
  [myBullets addObject: newBullet]; 
  //release the object here as its retained in the array 
  [newBullet release]; 

`myBullets` now has 5 bullets in it.  Then to modify the object:

// Retrive an item
theBullet = [myBullets objectAtIndex:i]; 
//do stuff or modify theBullet 
theBullet.position.x += 1;  

To remove an object from the array use:

//removes the 3rd item //remember an array starts at 0! 
[myBullets removeObjectAtIndex:2]; 

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