AudioManger和AudioSystem的关系

来源:互联网 发布:常见的数据库管理系统 编辑:程序博客网 时间:2024/05/16 18:03
    // This section re-defines new output device constants from AudioSystem, because the AudioSystem    // class is not used by other parts of the framework, which instead use definitions and methods    // from AudioManager. AudioSystem is an internal class used by AudioManager and AudioService.    /** @hide     * The audio device code for representing "no device." */    public static final int DEVICE_NONE = AudioSystem.DEVICE_NONE;    /** @hide     *  The audio output device code for the small speaker at the front of the device used     *  when placing calls.  Does not refer to an in-ear headphone without attached microphone,     *  such as earbuds, earphones, or in-ear monitors (IEM). Those would be handled as a     *  {@link #DEVICE_OUT_WIRED_HEADPHONE}.     */    public static final int DEVICE_OUT_EARPIECE = AudioSystem.DEVICE_OUT_EARPIECE;    /** @hide     *  The audio output device code for the built-in speaker */    public static final int DEVICE_OUT_SPEAKER = AudioSystem.DEVICE_OUT_SPEAKER;    /** @hide     * The audio output device code for a wired headset with attached microphone */    public static final int DEVICE_OUT_WIRED_HEADSET = AudioSystem.DEVICE_OUT_WIRED_HEADSET;    /** @hide     * The audio output device code for a wired headphone without attached microphone */    public static final int DEVICE_OUT_WIRED_HEADPHONE = AudioSystem.DEVICE_OUT_WIRED_HEADPHONE;    /** @hide     * The audio output device code for generic Bluetooth SCO, for voice */    public static final int DEVICE_OUT_BLUETOOTH_SCO = AudioSystem.DEVICE_OUT_BLUETOOTH_SCO;    /** @hide     * The audio output device code for Bluetooth SCO Headset Profile (HSP) and     * Hands-Free Profile (HFP), for voice     */    public static final int DEVICE_OUT_BLUETOOTH_SCO_HEADSET =            AudioSystem.DEVICE_OUT_BLUETOOTH_SCO_HEADSET;    /** @hide     * The audio output device code for Bluetooth SCO car audio, for voice */    public static final int DEVICE_OUT_BLUETOOTH_SCO_CARKIT =            AudioSystem.DEVICE_OUT_BLUETOOTH_SCO_CARKIT;


之前对二者的关系不是特别的清楚. 现在搞清楚.


通过这段注释 我们可以很清晰的知道


 // This section re-defines new output device constants from AudioSystem, because the AudioSystem
    // class is not used by other parts of the framework, which instead use definitions and methods
    // from AudioManager. AudioSystem is an internal class used by AudioManager and AudioService.

AudioSystem 是 AudioManager and AudioService. 的  internal class 内部类, 不对别的模块提供支持. 



0 0