Fill view with buttons at random positions - ios

Question

i want to fill area (UIView) with buttons(UIButton) so that they do not intersect with each others.
My idea:
create initial button at random position in view;
fill view with other buttons from initial button (count < 20) that they do not intersect ~10 pixels from each other.
What have i done so far:
I created method:
-(void)generateButtonsForView:(UIView *)view buttonCount:(int)count
{
//get size of main view
float viewWidth = view.frame.size.width;
float viewHeight = view.frame.size.height;
//set button at random position
UIButton *initialButton = [[UIButton alloc] initWithFrame:CGRectMake(arc4random() % (int)viewWidth,
arc4random() % (int)viewHeight,
buttonWidth, buttonHeight)];
[initialButton setBackgroundImage:[UIImage imageNamed:#"button"] forState:UIControlStateNormal];
[view addSubview:initialButton];
// set count to 20 - max number of buttons on screen
if (count > 20)
count = 20;
//fill view with buttons from initial button +- 10 pixels
for (int i=0;i<=count;i++)
{
//button
UIButton *otherButtons = [[UIButton alloc] init];
[otherButtons setBackgroundImage:[UIImage imageNamed:#"button"] forState:UIControlStateNormal];
...//have no idea what to do here
}
}
So i'm confused on the place where i want to generate the position of the other buttons, depending on the initial button. I do not know how to generate theirs position that they were at a distance of 5-10 pixels from each other... Any ideas how to realise this? Thanks!

Answer 1

Here's an example with views rather than buttons, but the concept is the same. I use CGRectInset to give the new potential view a buffer of 10 points around it, then look for whether the new view intersects any of the other views. If there's no intersection, add the subview, if there is, try again with a new random location.
-(void)generateButtonsForView {
float viewWidth = self.view.frame.size.width;
float viewHeight = self.view.frame.size.height;
UIView *initialView = [[UIView alloc] initWithFrame:CGRectMake(arc4random() % (int)viewWidth, arc4random() % (int)viewHeight, 50, 30)];
initialView.backgroundColor = [UIColor redColor];
[self.view addSubview:initialView];
int numViews = 0;
while (numViews < 19) {
BOOL goodView = YES;
UIView *candidateView = [[UIView alloc] initWithFrame:CGRectMake(arc4random() % (int)viewWidth, arc4random() % (int)viewHeight, 50, 30)];
candidateView.backgroundColor = [UIColor redColor];
for (UIView *placedView in self.view.subviews) {
if (CGRectIntersectsRect(CGRectInset(candidateView.frame, -10, -10), placedView.frame)) {
goodView = NO;
break;
}
}
if (goodView) {
[self.view addSubview:candidateView];
numViews += 1;
}
}
}