How to Keep Sound Turned Off - ios

Question

I have a two buttons. One that shows when the sound is playing and one when the sound isn't playing. However, when I switch it off and switch view controllers. And i come back to the main menu view controller the sound is back on. I want to keep the sound on or off based on the user setting.
(IBAction)pauseSound
{
BOOL shouldPlaySound = YES;
[[NSUserDefaults standardUserDefaults] setBool:shouldPlaySound forKey:#"shouldPlaySound"];
if (![sound isPlaying]) {
[sound play];
[soundButton setBackgroundImage:[UIImage imageNamed:#"SoundOn.png"] forState:UIControlStateNormal];
}else {
[sound pause];
[soundButton setBackgroundImage:[UIImage imageNamed:#"SoundOff.png"] forState:UIControlStateNormal];
}
[[NSUserDefaults standardUserDefaults] synchronize];
}

Answer 1

A good way to do this is saving wether or not to play the Sound in the NSUserDefaults, so the setting is remembered by your app. Set it i.e. via
BOOL shouldMuteSound = ...//set it corresponding to your button presses/visibility
[[NSUserDefaults standardUserDefaults] setBool:shouldMuteSound forKey:#"shouldMuteSound"];
//call this to immediatly update the userDefaults
[[NSUserDefaults standardUserDefaults] synchronize];
And load it via
BOOL shouldMuteSound = [[NSUserDefaults standardUserDefaults] boolForKey:#"shouldMuteSound"];
I didn't get it at first that the buttons are inside the same viewController that plays the sound. That code should help you:
-(void)viewDidAppear:(BOOL)animated{
[super viewDidAppear:animated];
BOOL shouldMuteSound = [[NSUserDefaults standardUserDefaults] boolForKey:#"shouldMuteSound"];
if(!shouldMuteSound){
[self playSound];
}else{
[self stopSound];
}
}
- (void)playSound{
if(!sound){
NSString *path = [[NSBundle mainBundle] pathForResource:#"Main Menu" ofType:#"mp3"];
sound = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] error:NULL];
sound.numberOfLoops = -1;
}
if (![sound isPlaying]){
[sound play];
}
[soundButton setBackgroundImage:[UIImage imageNamed:#"SoundOn.png"] forState:UIControlStateNormal];
}
- (void)stopSound{
[sound pause];
[soundButton setBackgroundImage:[UIImage imageNamed:#"SoundOff.png"] forState:UIControlStateNormal];
}
- (IBAction)soundButtonTapped{
BOOL shouldMuteSound = [[NSUserDefaults standardUserDefaults] boolForKey:#"shouldMuteSound"];
shouldMuteSound = !shouldMuteSound;
[[NSUserDefaults standardUserDefaults] setBool:shouldMuteSound forKey:#"shouldMuteSound"];
[[NSUserDefaults standardUserDefaults] synchronize];
if(shouldMuteSound){
[self stopSound];
}else{
[self playSound];
}
}