android - 在android中悬挂音频焦点

Question

我正在开发一个使用音频焦点功能来播放 TextToSpeech 的应用程序。

正常场景 - 播放音乐 -> 开始 TTS -> TTS 获得瞬时焦点 -> 完成 -> 音乐播放获得焦点。

错误场景 - 播放音乐 -> 启动 TTS -> TTS 获得瞬时焦点 -> 已接电话 -> TTS 焦点被放弃 -> 通话结束 -> 媒体播放器和 TTS 都获得焦点以高音量播放。

有没有其他方法来处理这种情况

下面是焦点监听器代码

 am.requestAudioFocus(afChangeListener,
                            // Use the music stream.
                            AudioManager.STREAM_MUSIC,
                            // Request permanent focus.
                            AudioManager.AUDIOFOCUS_GAIN_TRANSIENT);

和

回调方法

  if (focusChange == AudioManager.AUDIOFOCUS_LOSS_TRANSIENT) {
            Log.d("READOUT", "Focus AUDIOFOCUS_LOSS_TRANSIENT " + getTTS().isSpeaking() + "SDK version = " + Build.VERSION.SDK_INT);
            if (getTTS().isSpeaking()) {
                startReadout = true;
                stopReading();
            }
        } else if (focusChange == AudioManager.AUDIOFOCUS_GAIN || focusChange == AudioManager.AUDIOFOCUS_GAIN_TRANSIENT || focusChange == AudioManager.AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK) {
            Log.d("READOUT", "Focus Gain "+ focusChange);
            listnerTTSCallbacks.resumeTTS();
        } else if (focusChange == AudioManager.AUDIOFOCUS_LOSS) {
            Log.e("READOUT", "Focus AUDIOFOCUS_LOSS");
            stopReading();
        }