增加按鍵音

在frameworks/base/policy/src/com/android/internal/policy/impl/PhoneWindowManager.java中的
interceptKeyBeforeDispatching函數中增加以下:

if(!down)
{
                AudioManager am = (AudioManager)mContext.getSystemService(Context.AUDIO_SERVICE);
                am.playSoundEffect(SoundEffectConstants.CLICK);

}