How to change device Volume on iOS - not music volume

Question

I want to change the device volume on iOS (iphone).

I know that i can change the volume of music library with this lines below:

//implement at firs         


        

Answer 1

You have to use applicationMusicPlayer instead of iPodMusicPlayer to set the system volume:

#import 
musicPlayer = [MPMusicPlayerController applicationMusicPlayer];
musicPlayer.volume = 1; // max volume
musicPlayer.volume = 0; // min volume (mute)
musicPlayer.volume = 0.0625; // 1 bar on the overlay volume display