iphone - 播放最大 speakerPhone 音量，然后使用 AVAudioPlayer 重置为之前的音量 --- IOS

Question

我已经能够将我的音频路由到免提电话，但它仍然无法以可能的最大音量播放。我试过 [audioAlert setVolume:1.0]，它仍然保持在用户当前设置的音量。如果有人知道我做错了什么，我将不胜感激。

这是我的代码:

AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:NULL];

    UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;
    AudioSessionSetProperty (kAudioSessionProperty_OverrideAudioRoute,sizeof (audioRouteOverride),&audioRouteOverride);

    NSURL* soundUrl = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"HsTR_soundEFX_2-1" ofType:@"mp3"]];
   audioAlert= [[AVAudioPlayer alloc] initWithContentsOfURL:soundUrl error:nil];
    audioAlert.delegate = self;
    [audioAlert setVolume:1.0];
    [audioAlert prepareToPlay];
    [audioAlert play];

感谢 PaulPerry!

现已解决:

我添加了一些额外的内容以使用以下代码将其设置回之前的卷:

 AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:NULL];

    UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;
    AudioSessionSetProperty (kAudioSessionProperty_OverrideAudioRoute,sizeof (audioRouteOverride),&audioRouteOverride);

    NSURL* soundUrl = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"HsTR_soundEFX_2-1" ofType:@"mp3"]];
   audioAlert= [[AVAudioPlayer alloc] initWithContentsOfURL:soundUrl error:nil];
    audioAlert.delegate = self;
    [audioAlert prepareToPlay];
    float maxVolume = 1.0;
    float currentVolume=[MPMusicPlayerController applicationMusicPlayer].volume;
    [[MPMusicPlayerController applicationMusicPlayer] setVolume:maxVolume];
    [audioAlert play];
   //set up timer to wait until audioAlert is finished playing,
   // and then call the line below to set the volume back to it's original setting
    [[MPMusicPlayerController applicationMusicPlayer]setVolume:currentVolume];

Answer 1

这会将整个系统的音量重置为最大。

float 量 = 1.0；[[MPMusicPlayerController applicationMusicPlayer] setVolume:volume];