Help on Objective C NSMutableArrays and For Loops?

[Kenenth]

I am 12 and trying to make an iphone app. In a part of the app, paratroopers must scroll down the screen, but I have to keep track of them. I have done so with an NSMutableArray. I create a random image at 1 y and a random value x and I store it in my array. I go through all of the items with a for loop and I am trying to lower the y value so that they come down the screen. this is my code for it:

-(void)lowerParatroopers {

for (int x=1; x<=[array count]; x++) {
((UIImageView *) [array objectAtIndex:x ]).center.y = ((UIImageView *)[array objectAtIndex:x ]).center.y-1;
}
}


Every time I change it to work another error pops up. Can you please share the code to be able to do this function? Or if i am close to getting it right, can you please tell me what I am doing wrong? Thanks!

[iisword]

1)Don't come in here and start announcing your age, that will tick me off
2)Start x at 0
3)

[[array objectAtIndex:x] setCenter:CGPointMake([[[array objectAtIndex:x] center] x], [[[array objectAtIndex:x] center] y]-1)];

[TUX2K]

Like iisword already said array start at 0.

also make sure that the x is always smaller the the count:

for (int x=0; x < [array count]; x++) {

Else you will get an index out of bounds error.

[smasher]

You got two right answers, but I'm going to put them together and make them easier to read.

for (int x=0; x < [array count]; x++) {
     UIImageView *myView = [array objectAtIndex:x];
     CGPoint newCenter = CGPointMake(myView.center.x, myView.center.y-1);
     myView.center = newCenter;
}

You could also go one easier as long as you don't intend to remove objects from the array:

for (UIImageView *myView in array) {
     CGPoint newCenter = CGPointMake(myView.center.x, myView.center.y-1);
     myView.center = newCenter;
}