Iphone – Why does iPod’s audio not fade back in after the app caused it to fade out

cocoa-touchiphone

My app needs to play some audio files and I want to fade-out the iPod sound, play my file, and then as soon as my audio stops playing fade-in iPod again (just like iPhone handles iPod music when an incoming call comes in)

I'm setting up my app's Audio Session to be kAudioSessionCategory_MediaPlayback and then just before I play my file I call AudioSessionSetActive (true)
then when my file ends playing I call AudioSessionSetActive (false)

What happens is that the iPod audio fades-out with the AudioSessionSetActive (true) call, but it never fades-in again after I call AudioSessionSetActive (false)

I'm using AVFoundation class to play my audio, I audioPlayerDidFinishPlaying in my delegate method and that's where I call AudioSessionSetActive (false).

What am I missing here? Why doesn't the iPod fade-in when I deactive my audio session? Do I have the wrong Audio Session Category for this?

Best Solution

Ok, this is lovely. In iPhone OS3, see AddMusic example.

In essence, you do this:

#import <MediaPlayer/MediaPlayer.h>
...
[[MPMusicPlayerController iPodMusicPlayer] pause]
...(play your audio, with AmbientSound category)
[[MPMusicPlayerController iPodMusicPlayer] play]

This is basic. You can also add fadeout by looping volume change etc.

Related Solutions

IPhone – AVAudioPlayer, kAudioSessionCategory_AmbientSound and iPod music

Okay just thought I'd keep everyone posted in case it helps someone else... what I did was probably kind of hackish, but seems to do the trick!


    UInt32 isPlaying;
    UInt32 propertySize = sizeof(isPlaying);
    OSStatus status;

    // check to see if their iPod music is playing
    status = AudioSessionGetProperty(kAudioSessionProperty_OtherAudioIsPlaying, &propertySize, &isPlaying);

    // set the session category accordingly
    if(!isPlaying) {
      NSLog(@"...SoloAmbientSound");
      UInt32 sessionCategory = kAudioSessionCategory_SoloAmbientSound;
      AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(sessionCategory), &sessionCategory);
    }else{
      NSLog(@"...AmbientSound");
      UInt32 sessionCategory = kAudioSessionCategory_AmbientSound;
      AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(sessionCategory), &sessionCategory);
    }

Iphone – AVAudioPlayer fade volume out

Here's how I'm doing it:

-(void)doVolumeFade
{  
    if (self.player.volume > 0.1) {
        self.player.volume = self.player.volume - 0.1;
        [self performSelector:@selector(doVolumeFade) withObject:nil afterDelay:0.1];       
     } else {
        // Stop and get the sound ready for playing again
        [self.player stop];
        self.player.currentTime = 0;
        [self.player prepareToPlay];
        self.player.volume = 1.0;
    }
}

11 years later: do note that setVolume#fadeDuration now exists!

Best Solution

Related Solutions

IPhone – AVAudioPlayer, kAudioSessionCategory_AmbientSound and iPod music

Iphone – AVAudioPlayer fade volume out

Related Question