Main Scene and Game State - Learn SpriteBuilder for iOS Game Development - page 242

Persisting the Volume Slider Values
With the GameState class in place, you can now connect the sliders with the two
volume properties in the GameState singleton to persist their values.
Add the lines highlighted in Listing 7-14 to SettingsLayer.m .
Listing 7-14 . Connecting the slider values with GameState properties
#import "SettingsLayer.h"
#import "MainMenuButtons.h"
#import "GameState.h"
@implementation SettingsLayer
{
__weak CCSlider* _musicSlider;
__weak CCSlider* _effectsSlider;
}
-(void) didLoadFromCCB
{
GameState* gameState = [GameState sharedGameState];
_musicSlider.sliderValue = gameState.musicVolume;
_effectsSlider.sliderValue = gameState.effectsVolume;
}
-(void) volumeDidChange:(CCSlider*)sender
{
if (sender == _musicSlider)
{
[GameState sharedGameState].musicVolume
= _musicSlider.sliderValue;
}
else if (sender == _effectsSlider)
{
[GameState sharedGameState].effectsVolume
= _effectsSlider.sliderValue;
}
}
-(void) shouldClose
{
[[NSUserDefaults standardUserDefaults] synchronize];