如何通過呼叫接收器揚聲器播放AVSpeechSynthesizer？

Question

我喜歡通過呼叫接收器揚聲器播放音頻，目前我正在使用它來播放某些文本作爲音頻。

AVSpeechUtterance *utterance = [AVSpeechUtterance speechUtteranceWithString:_strTextCheck]; 
    AVSpeechSynthesizer *syn = [[AVSpeechSynthesizer alloc] init]; 
    [syn speakUtterance:utterance]; 

我得到了，但是這不是AVSpeechSynthesizer：

[AVAudioSession overrideOutputAudioPort:AVAudioSessionPortOverrideSpeaker error:&error]; 

正確的在一個普通的揚聲器工作，但我想打通過電話受話器揚聲器播放，是有可能做到這一點？

Answer 1

默認行爲是通過呼叫接收器播放。所以，如果你取消設置覆蓋 - 或不設置它擺在首位 - 你應該得到你之後的行爲：

[[AVAudioSession sharedInstance] 
    overrideOutputAudioPort:AVAudioSessionPortOverrideNone 
         error:nil]; 

下面是一個完整的例子。您還需要設置audioSession類別。

- (void)playVoice { 
    [[AVAudioSession sharedInstance] 
      setCategory:AVAudioSessionCategoryPlayAndRecord 
        error:nil]; 

    //try one or the other but not both... 

    //[self playVoiceOnSpeaker:@"test test test"]; 

    [self playVoiceOnReceiver:@"test test test"]; 

} 

-(void)playVoiceOnSpeaker:(NSString*)str 
{ 
    [[AVAudioSession sharedInstance] 
     overrideOutputAudioPort:AVAudioSessionPortOverrideSpeaker 
          error:nil]; 
    [self playVoiceByComputer:str]; 
} 

-(void)playVoiceOnReceiver:(NSString*)str 
{ 
    [[AVAudioSession sharedInstance] 
     overrideOutputAudioPort:AVAudioSessionPortOverrideNone 
          error:nil]; 
    [self playVoiceByComputer:str]; 
} 

-(void)playVoiceByComputer:(NSString*)str 
{ 
    AVSpeechUtterance *utterance = 
      [AVSpeechUtterance speechUtteranceWithString:str]; 
    AVSpeechSynthesizer *syn = [[AVSpeechSynthesizer alloc] init]; 
    [syn speakUtterance:utterance]; 
} 

Answer 2

這爲我工作：

try audioSession.setCategory(AVAudioSessionCategoryPlayAndRecord, with: [.defaultToSpeaker])