Ios 如何使UISlider平稳运行？

我使用AVPlayer和UISlider作为视频播放的擦洗器。 代码如下：

__weak __typeof__(self) weakSelf = self;
avPlayerTimeObserver_ = [_avPlayer addPeriodicTimeObserverForInterval:CMTimeMake(1, 10)
                                        queue:dispatch_get_main_queue()
                                   usingBlock:^(CMTime time) {
                                       if (weakSelf.avPlayer.status == AVPlayerStatusReadyToPlay && weakSelf.avPlayer.currentItem.status == AVPlayerItemStatusReadyToPlay) {
                                           NSTimeInterval currentTime = CMTimeGetSeconds(_avPlayer.currentItem.currentTime);
                                           NSLog("currentTime: %@");
                                           [self.playerView.scrubber setValue:currentTime];

                                       }
}];

通过检查登录控制台，slider的值在一秒钟内设置了多次：

但是滑块的拇指每1秒只会一步一步地移动，这是我设置的间隔CMTimeMake（1,10）或CMTimeMake（1,30）甚至CMTimeMake（1100）

---

如何使其更加平滑？

尝试

[self.playerView.scriber设置值：currentTime动画：是]
2014-07-28 10:41:07.044 TestAVPlayer[16733:90b] currentTime: 19.609156
2014-07-28 10:41:07.145 TestAVPlayer[16733:90b] currentTime: 19.709789
2014-07-28 10:41:07.245 TestAVPlayer[16733:90b] currentTime: 19.809995
2014-07-28 10:41:07.345 TestAVPlayer[16733:90b] currentTime: 19.909412
2014-07-28 10:41:07.445 TestAVPlayer[16733:90b] currentTime: 20.009458
2014-07-28 10:41:07.545 TestAVPlayer[16733:90b] currentTime: 20.109446
2014-07-28 10:41:07.644 TestAVPlayer[16733:90b] currentTime: 20.209153
2014-07-28 10:41:07.744 TestAVPlayer[16733:90b] currentTime: 20.309311
2014-07-28 10:41:07.844 TestAVPlayer[16733:90b] currentTime: 20.409178
2014-07-28 10:41:07.944 TestAVPlayer[16733:90b] currentTime: 20.509420
2014-07-28 10:41:08.045 TestAVPlayer[16733:90b] currentTime: 20.610105
2014-07-28 10:41:08.144 TestAVPlayer[16733:90b] currentTime: 20.709268
2014-07-28 10:41:08.245 TestAVPlayer[16733:90b] currentTime: 20.809690
2014-07-28 10:41:08.345 TestAVPlayer[16733:90b] currentTime: 20.909868