问题很简单:下面的两种方法哪个运行更快?原因?
CGFloat sum = 0;
for (UIView *v in self.subviews)
sum += v.frame.size.height;
第二种:
CGFloat sum = [[self.subviews valueForKeyPath:@"@sum.frame.size.height"] floatValue];
问题很简单:下面的两种方法哪个运行更快?原因?
CGFloat sum = 0;
for (UIView *v in self.subviews)
sum += v.frame.size.height;
第二种:
CGFloat sum = [[self.subviews valueForKeyPath:@"@sum.frame.size.height"] floatValue];