IOS/Swift暂停和恢复图层动画

   //mySuperLayer父图层    CFTimeInterval pausedTime = [self.mySuperLayer timeOffset];    if (pausedTime > 0)//在暂停后才能使用    {        self.mySuperLayer.speed = 1.0;        self.mySuperLayer.timeOffset = 0.0;        self.mySuperLayer.beginTime = 0.0;        CFTimeInterval timeSincePause = [self.mySuperLayer convertTime:CACurrentMediaTime() fromLayer:nil] - pausedTime;        self.mySuperLayer.beginTime = timeSincePause;    }

    CFTimeInterval pausedTime = [self.mySuperLayer convertTime:CACurrentMediaTime() fromLayer:nil];    self.mySuperLayer.speed = 0.0;    self.mySuperLayer.timeOffset = pausedTime;