用CALayer下边框向下滑动UIView

Question

我试图在单击栏按钮时滑下UIView。到目前为止，这么好，但我遇到了一个问题。为了美观，我在视图中添加了底部边框，并且我想用UIView滑动动画为底部边框设置动画。问题是CABasicAnimation是有限的，不允许CurveEaseIn。所以，下边框比UIView更快。

我该如何补救？

[UIView animateWithDuration:.5 delay:0.0 options:UIViewAnimationOptionCurveEaseIn animations:^{ 
      _navView.frame = CGRectMake(0, 0, 320, 350); 
      _navView.frame = CGRectMake(0, 0, 320, 350); 

      CALayer *oldLayer = [[_navView.layer sublayers] lastObject]; 
      CGRect oldFrame = oldLayer.frame; 
      CGRect newFrame = oldFrame; 
      newFrame.origin = CGPointMake(0, 350); 

      // Prepare the animation from the old size to the new size 
      CABasicAnimation *theAnimation = [CABasicAnimation animationWithKeyPath:@"frame"]; 
      theAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn]; 
      theAnimation.duration = .5; 
      // Make this view controller the delegate so it knows when the animation starts and ends 
      theAnimation.delegate=self; 
      // Use fromValue and toValue 
      theAnimation.fromValue = [NSValue valueWithCGRect:oldFrame]; 
      theAnimation.toValue = [NSValue valueWithCGRect:newFrame]; 


      // Update the frame of the layer 
      oldLayer.frame = newFrame; 

      // Add the animation to the layer 
      [oldLayer addAnimation:theAnimation forKey:@"frame"]; 
    } completion:^(BOOL finished) { 
    }]; 

Answer 1

最简单的方案几乎可以肯定是使用视图，而不是一个层，你的下边框，然后使用，而不是核心动画UIKit的动画边框视图。