how to remove subviews from scrollview?

Question

how do i remove all subviews from my scrollview...

i have a uiview and a button above it in the scrollview something like this....

here is my code to add sub

Answer 1

The best and easiest is to use

for(UIView *subview in [scrollView subviews])
{
  [subview removeFromSuperview];
}

This indeed causes crash as the basic rule is array shouldn't modified while being enumerated, to prevent that we can use

[[scrollView subviews] 
           makeObjectsPerformSelector:@selector(removeFromSuperview)];

But sometimes crash is still appearing because makeObjectsPerformSelector: will enumerate and performs selector, Also in iOS 7 ui operations are optimized to perform more faster than in iOS 6, Hence the best way to iterate array reversely and remove

NSArray *vs=[scrollView subviews];
for(int i=vs.count-1;i>=0;i--)
{
    [((UIView*)[vs objectAtIndex:i]) removeFromSuperview];
}

Note : enumerating harms modification but not iterating...