Please help! Creating new objects (from array?) after an object completes task - iphone

Question

I am writing an iPhone application and here is the overall synopsis:
An object is on the screen and moves based on accelerometer input - I have that working - it moves to the edge of the screen and doesn't go off = perfect. Now, what I want to happen is as soon as that object hits any of the four screen edges, it should stop and stay put on the screen, and a new object should 'appear' and start moving due to the accelerometer input, so now two objects would be on the screen, but only 1 moving. Eventually there could be 20 objects built up around the edge, but only 1 object will be moving at a time.
So I have now gotten the help I needed to check for edge hits etc, but I am now trying to switch the way I was getting boxes to show up on the screen. I originally was putting images on the screen through the view controller, but now what I want to do is start with one box in the center, when it hits an edge, it should stop and stay, and a new image will appear in the center and start moving due to accel input as described above. So do I just use an array to pull the images from? Do I not even put .png's on the view controller and should I just code it? Here is some of what I have trying to do this through an array:
//In my .h
UIImageView *blocks;
NSString *blockTypes[3];
//In my .m
blockTypes[0] = #"greenBox1.png";
blockTypes[1] = #"greenBox2.png";
blockTypes[2] = #"greenBox3.png";
Thanks in advance for any help! The help so far has been great!

Answer 1

You should't test if newX and newY are equal to 30 and 50. You should test if they are less than 30 and 50 respectively.
Edit:
I would do it like this:
loat newX = [mutableBoxArray lastObject].center.x + (accel.x * 12);
float newY = [mutableBoxArray lastObject].center.y + (accel.y * -12);
if(newX > 30 && newY > 50 && newX < 290 && newY < 430) {
[[mutableBoxArray lastObject] setCenter: CGPointMake(newX, newY)];
} else {
MyBox *myBox = [[MyBox alloc] init];
[mutableBoxArray addObject: myBox];
[myBox release];
}
Edit 2:
Add the following in your interface file
NSMutableArray *mutableBoxArray;
NSArray *imageNamesArray;
Then in your implementation file in the loadView add
mutableBoxArray = [[NSMutableArray alloc] init];
imageNamesArray = [[NSArray alloc] initWithObjects: #"orangeBox1.png",
#"blueBox1.png", #"greenBox1.png", #"pinkBox1.png", nil];
Then change the above method to
static NSInteger imageInt = 0;
loat newX = [mutableBoxArray lastObject].center.x + (accel.x * 12);
float newY = [mutableBoxArray lastObject].center.y + (accel.y * -12);
if(newX > 30 && newY > 50 && newX < 290 && newY < 430) {
[[mutableBoxArray lastObject] setCenter: CGPointMake(newX, newY)];
} else {
if (imageInt < [imageNamesArray count]) {
UIImage *image = [UIImage imageNamed: [imageNamesArray objectAtIndex: imageInt++]];
UIImageView *imageView = [[UIImageView alloc] initWithImage: image];
[imageView setCenter: CGPointMake(100.0f, 100.0f)];
[mutableBoxArray addObject: imageView];
[imageView release];
}
}