Find subviews within rectangle

问题:

I have a large UIView with many small subviews. I need to find all subviews within an area. I am currently iterating through subviews and using CGRectContainsPoint. This works, but 90% of the subviews are usually not within my rectangle of interest.

Is there a more efficient way to find all subviews within a rectangle?

Thanks

回答1:

CGRectContainsRect would be more appropriate. You'd still need to loop through all subviews that might be in your rect based on what you can assume about their positions, but CGRectContainsRect still makes more sense than CGRectContainsPoint.

CGRect area = CGRectMake(10,10,200,200);
NSMutableArray *viewsWithinArea = [[NSMutableArray alloc] init];
for (UIView *aView in [self.view subviews]) {
   if(CGRectContainsRect(area,aView.frame)) [views addObject:aView];
}

回答2:

@james_womack's answer in Swift:

func subviewsWithin(area: CGRect) -> [UIView] {
    return subviews.filter { area.contains($0.frame) }
}