问题描述

AVPlayer控制音量播放

开发一个自定义播放，用到AVPlayer类，现在想加入UISlider控制音量。

实现代码：

NSMutableArray *allAudioParams = [NSMutableArray array];AVMutableAudioMixInputParameters *audioInputParams =[AVMutableAudioMixInputParameters audioMixInputParameters];[audioInputParams setVolume:volumeSlider.value atTime:kCMTimeZero];[allAudioParams addObject:audioInputParams];AVMutableAudioMix *audioZeroMix = [AVMutableAudioMix audioMix];[audioZeroMix setInputParameters:allAudioParams];[self.playerItem setAudioMix:audioZeroMix];

步骤地为什么不好使。请大家帮忙，谢谢。

解决方案

NSArray *audioTracks = [asset tracksWithMediaType:AVMediaTypeAudio];NSMutableArray *allAudioParams = [NSMutableArray array];for (AVAssetTrack *track in audioTracks) {  AVMutableAudioMixInputParameters *audioInputParams =     [AVMutableAudioMixInputParameters audioMixInputParameters];  [audioInputParams setVolume:volume atTime:kCMTimeZero];  [audioInputParams setTrackID:[track trackID]];  [allAudioParams addObject:audioInputParams];}AVMutableAudioMix *audioMix = [AVMutableAudioMix audioMix];[audioMix setInputParameters:allAudioParams];[playerItem setAudioMix:audioMix];

用这段代码控制音量

解决方案二：

-(void)doVolumeFade{      if (self.player.volume > 0.1) {        self.player.volume = self.player.volume - 0.1;        [self performSelector:@selector(doVolumeFade) withObject:nil afterDelay:0.1];            } else {        // Stop and get the sound ready for playing again        [self.player stop];        self.player.currentTime = 0;        [self.player prepareToPlay];        self.player.volume = 1.0;    }}