如何访问iPhone系统首选项

有关静音开关,请参见此处。 http://www.restoroot.com/Blog/2008/12/25/audiosessioninitialize-workarounds/

基本上你只是需要这个。

// "Ambient" makes it respect the mute switch
    // Must call this once to init session
    if (!gAudioSessionInited)
    {
        AudioSessionInterruptionListener    inInterruptionListener = NULL;
        OSStatus    error;
        if ((error = AudioSessionInitialize (NULL, NULL, inInterruptionListener, NULL)))
        {
            NSLog(@"*** Error *** GBMusicTrack - initWithPath: error in AudioSessionInitialize: %d.", error);
        }
        else
        {
            gAudioSessionInited = YES;
        }
    }

    SInt32  ambient = kAudioSessionCategory_AmbientSound;
    if (AudioSessionSetProperty (kAudioSessionProperty_AudioCategory, sizeof (ambient), &ambient))
    {
        NSLog(@"*** Error *** GBMusicTrack - initWithPath: could not set Session property to ambient.");
    }

至于读取系统的首选项,至少不能不通过公共API!