ios – CAKeyFrameAnimation在重复之前延迟

这是我的代码：

CGPathRef aPath;
aPath = CGPathCreateWithEllipseInRect(CGRectMake(0,SIZE,SIZE),NULL);

[CATransaction begin];

arcAnimation = [CAKeyframeAnimation animationWithKeyPath: @"position"];
[arcAnimation setBeginTime:CACurrentMediaTime()];
[arcAnimation setDuration: 1.5];
[arcAnimation setTimingFunction:[camediatimingFunction functionWithName:kcamediatimingFunctionLinear]];
[arcAnimation setAutoreverses: NO];
[arcAnimation setRepeatCount:HUGE_VALF];
arcAnimation.removedOnCompletion = NO;
arcAnimation.fillMode = kCAFillModeRemoved;
[arcAnimation setPath: aPath];
[ball.layer addAnimation: arcAnimation forKey: @"position"];
[CATransaction commit];
CFRelease(aPath);