+(UIView*)addCoverView{ UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width, [UIScreen mainScreen].bounds.size.height)]; view.backgroundColor = [UIColor blackColor]; view.alpha = 0.5; [[UIAp
+(UIView*)addCoverView{
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width, [UIScreen mainScreen].bounds.size.height)];
view.backgroundColor = [UIColor blackColor];
view.alpha = 0.5;
[[UIApplication sharedApplication].keyWindow addSubview:view];
return view;
}
+(void)removeCoverView:(UIView*)view{
[view removeFromSuperview];
}