using c# on Unity 3D
// Set up when program start
if (PlayerPrefs.GetFloat("BackGroundVolume") == -20f)
{
backgroudGroup.SetFloat("Master", -80f);
}
else
{
backgroudGroup.SetFloat("Master", PlayerPrefs.GetFloat("BackGroundVolume"));
}
// volume save & change System Volume
public void Save()
{
PlayerPrefs.SetFloat("BackGroundVolume", backGroundVolume.value);
PlayerPrefs.SetFloat("EffectVolume", effectVolume.value);
PlayerPrefs.SetFloat("NatureVolume", natureVolume.value);
AudioManager.instance.SetSoundVolume();
PlayerPrefs.Save();
}