微信二维码扫描时的动画效果 线

UIView *line = [[UIView alloc] initWithFrame:CGRectMake((viewWidth - width)/2, origin_y, width, 1)];

    [self.view addSubview:line];

    line.backgroundColor = [UIColor redColor];

    

    [UIView beginAnimations:@"animationID" context:NULL];

    [UIView setAnimationDuration:4];

    

    [UIView setAnimationCurve:UIViewAnimationCurveLinear];

    [UIView setAnimationTransition:UIViewAnimationTransitionCurlDown forView:line cache:YES];  //这句话估计得注释掉才行，有一次就因为这句话出现个小问题

    [UIView setAnimationRepeatCount:100];

    

    [line setFrame:CGRectMake((viewWidth - width)/2, origin_y+width, width, 1)];

    [UIView commitAnimations];

    

    [line release];