title: CAKeyframeAnimation beginTime
body: <p>I'm writing a simple project to learn CAKeyframeAnimation's. I have a small UIView rectangle, item1, that I am moving across the screen.</p>
  
  <pre><code>@interface ViewController ()
  @property (nonatomic, strong) UIView *item1;
  @end
  @implementation ViewController
  
  - (IBAction)StartButton:(id)sender
  {
  CAKeyframeAnimation *animateItem1 = [CAKeyframeAnimation animation];
  animateItem1.keyPath = @"position.x";
  animateItem1.values = @[@0, @15, @113, @123, @135];
  animateItem1.keyTimes = @[@0, @.50, @.80, @.90, @1.0];
  animateItem1.duration = 4.;
  // animateItem1.beginTime = 2.0;
  animateItem1.additive = YES;
  animateItem1.fillMode = kCAFillModeForwards;
  animateItem1.removedOnCompletion = NO;
  [self.item1.layer addAnimation:animateItem1 forKey:@"move rect1"];
  }
  
  -(void)viewWillAppear:(BOOL)animated
  {
  self.item1 = [[UIView alloc]initWithFrame:CGRectMake(100, 100, 10, 10)];
  self.item1.backgroundColor = [UIColor redColor];
  [self.view addSubview:self.item1];
  }
  </code></pre>
  
  <p>This runs as I expect it. But, if I un-comment the beginTime property. The animation just jumps to the end without executing each frame. After reading this explanation page, <a href="http://ronnqvi.st/controlling-animation-timing/" rel="nofollow">http://ronnqvi.st/controlling-animation-timing/</a>, I'm simply expecting the animation to start and begin 2.0 seconds after I begin the animation. Can you tell me what I'm doing wrong? Thank you.</p>