Android: 系统默认音量

frameworks\base\media\java\android\media\AudioManager.java /** @hide Default volume index values for audio streams */ public static final int[] DEFAULT_STREAM_VOLUME = new int[] { 4, // STREAM_VOICE_CALL 7, // STREAM_SYSTEM 5, // STREAM_RING 11, // STREAM_MUSIC 6, // STREAM_ALARM 5, // STREAM_NOTIFICATION 7, // STREAM_BLUETOOTH_SCO 7, // STREAM_SYSTEM_ENFORCED 11, // STREAM_DTMF 11 // STREAM_TTS };