android - Android : setVolume and setAudioStreamType(AudioManager.STREAM_VOICE_CALL);

Question

I am playing an audio file with an internal speaker using this code

audioManager = (AudioManager)Context.getSystemService(Context.AUDIO_SERVICE);
audioManager.setSpeakerphoneOn(false);
mediaPlayer.setAudioStreamType(AudioManager.STREAM_VOICE_CALL);

How can I set the volume?

Answer 1

adjustStreamVolume()上使用AudioManager。

不过，最好让用户通过音量控制按钮以正常方式设置音量。您可以通过 指示在您的活动中要控制的流setVolumeControlStream()。

Answer 2

am2 是 AudioManager 系统服务的一个实例。am2 = (AudioManager) getSystemService(Context.AUDIO_SERVICE);

// makes the media volume adjustment
public static int setVolume(int inputVol, Context sender) {
    int outVol;
    if (inputVol < 0)
        inputVol = 0;
    if (inputVol > am2.getStreamMaxVolume(AudioManager.STREAM_MUSIC))
        inputVol = am2.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
    am2.setStreamVolume(AudioManager.STREAM_MUSIC, inputVol,
            AudioManager.FLAG_SHOW_UI);
    outVol = am2.getStreamVolume(AudioManager.STREAM_MUSIC);
    return outVol;
}