我有一个应用程序使用 MPMusicPlayerController 播放背景音乐,使用 AVAudioPlayer 播放前景声音。我想控制相对音量,使 MPMusicPlayerController 低得多,但设置音量会改变整个系统的音量,就像使用手机侧面的按钮一样。有没有办法在不降低系统音量的情况下降低 MPMusicPlayerController 的音量?
MPMusicPlayerController *musicPlayer = [MPMusicPlayerController applicationMusicPlayer];
musicPlayer.volume = 0.1; // at this point the overall system volune has been set to 0.1
[musicPlayer setQueueWithItemCollection:collection];
[musicPlayer play];
AVAudioPlayer *player = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&err];
[player prepareToPlay];
[player setVolume: 1.0]; // I want this to be twice as loud as MPMusicPlayerController
[player play];
最佳答案
您需要学习如何“闪避”MPMusicPLayer。尝试在播放 AVAudioPlayer 之前和之后调用下面的方法。
基本上,[self setAudioSessionWithDucking:YES] 之前和 [self setAudioSessionWithDucking:NO] 之后。
- (void)setAudioSessionWithDucking:(BOOL)isDucking
{
AudioSessionSetActive(NO);
UInt32 overrideCategoryDefaultToSpeaker = 1;
AudioSessionSetProperty (kAudioSessionProperty_OverrideCategoryDefaultToSpeaker, sizeof (overrideCategoryDefaultToSpeaker), &overrideCategoryDefaultToSpeaker);
UInt32 overrideCategoryMixWithOthers = 1;
AudioSessionSetProperty (kAudioSessionProperty_OverrideCategoryMixWithOthers, sizeof (overrideCategoryMixWithOthers), &overrideCategoryMixWithOthers);
UInt32 value = isDucking;
AudioSessionSetProperty(kAudioSessionProperty_OtherMixableAudioShouldDuck, sizeof(value), &value);
AudioSessionSetActive(YES);
}
关于ios - 设置 iOS MPMusicPlayerController 相对于 AVAudioPlayer 的音量,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/17055234/