Creating 20 UIViews on different positions without overlapping - ios

Question

sorry, my english is not so good.
I try to create 20 UIViews with a fix height and width but different positions on the screen.
for( int i = 0; i < 20; i++ ) {
UIView *view = [[UIView alloc]init];
view.backgroundColor = [UIColor redColor];
view.tag = i;
randomX = fmod(arc4random(),((int)self.view.frame.size.width - view.frame.size.width));
randomY = fmod(arc4random(),((int)self.view.frame.size.height - view.frame.size.height));
view.frame = CGRectMake(randomX, randomY, 100, 100);
This is only a part of my program.
If i do it like this, the uiviews are created on the screen, but they overlap.
I know there is a function like CGRectIntersectRect but i don´t know how it works correctly in this context.
Can someone help me with this problem?

Answer 1

Here's a small snippet of code, not really tested, but I think it'll work (I suppose in theory it could run forever, but in reality it takes a split second :-) ) -
NSMutableArray *views = [NSMutableArray array];
for( int i = 0; i < 20; i++ )
{
UIView *view = [[UIView alloc]init];
view.backgroundColor = [UIColor redColor];
view.tag = i;
__block BOOL ok = YES;
do
{
CGFloat randomX = fmod(arc4random(),((int)self.view.frame.size.width - view.frame.size.width));
CGFloat randomY = fmod(arc4random(),((int)self.view.frame.size.height - view.frame.size.height));
view.frame = CGRectMake(randomX, randomY, 100, 100);
[views enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop)
{
CGRect rect1 = ((UIView *)obj).frame;
CGRect rect2 = view.frame;
if (CGRectIntersectsRect(rect1, rect2))
{
ok = NO;
*stop = YES;
}
else
ok = YES;
}];
}
while (!ok);
[self.view addSubview:view];
[views addObject:view];
}