Store ON/OFF switch in NSUserDefaults? - ios

Question

I have an app where I use NSUserDefaults to determine if it is the first time someone opens the app. If it is the first time, the app displays a tutorial page.
Now, I would like to change this so that if the user moves an ON/OFF switch to "ON", they will not see the tutorial when they start up the app. How do I store the user's selection of an ON/OFF switch in NSUserDefaults?

Answer 1

I did something like this with the following code:
Store it:
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
[userDefaults setBool:YES forKey:#"the_key"];
[[NSUserDefaults standardUserDefaults] synchronize]; //Thanks Henri Normak
Retrieve it:
[[NSUserDefaults standardUserDefaults] objectForKey:#"the_key"]

Answer 2

Wrap it in an NSNumber numberWithBool:.
[defaults setValue:[NSNumber numberWithBool:mySwitch.on] forKey:#"mySwitchValue"];
// and get it out
BOOL savedSwitch = [[defaults valueForKey:#"mySwitchValue"] boolValue];

Answer 3

You need two bool keys to be saved in NSUserDefaults to get the what you want. e.g. firstTime is used check first time app launch, showTutorial is used to check/save the switch change
You can set your boolean by using:
[[NSUserDefaults standardUserDefaults] setBool:YES forKey:#"firstTime"];
and read it by using this code:
if([[NSUserDefaults standardUserDefaults] boolForKey:#"showTutorial"] || [[NSUserDefaults standardUserDefaults] boolForKey:#"firstTime"]) {
[self displayTutorial];
[[NSUserDefaults standardUserDefaults] setBool:NO forKey:#"firstTime"];
}
else {
[self displayMainScreen];
}
Link the UISwitch on View from InterfaceBuilder to this action on valuechanged
-(IBAction)userSetOnOff:(id)sender
{
UISwitch *switchValue = sender;
if (switchValue.on){
[[NSUserDefaults standardUserDefaults] setBool:YES forKey:#"showTutorial"];
}
else{
[[NSUserDefaults standardUserDefaults] setBool:NO forKey:#"showTutorial"];
}
}

Answer 4

In one of my apps I check to see if NSUserDefaults has been used and if not set the one standard User Default variable.
-(id) init
{
standardUserDefaults = [NSUserDefaults standardUserDefaults];
NSString *testInitState = [standardUserDefaults stringForKey:kInstallInit];
if (testInitState == nil)
{
#if(kStateModelDebug)
NSLog(#" State Model: First time initialized");
#endif
[self.standardUserDefaults setObject:#"true" forKey:kInstallInit];
[self.standardUserDefaults synchronize];
// Start the tutorials, init DB, etc
}
else
{
#if(kStateModelDebug)
NSLog(#" State Model has ALREADY been initialized");
#endif
// Read other state variables and/or init the startup processes
}
return self;
}
So far , up to ios 5.0 and the new 6.0, this has been a solution. Looking for comments on this solution.

Answer 5

One way is to simply persist a string with the switch status. If the user prefers the on position you'd store the string #"on". Else store the string #"off".
- (void) toggleUserPreference:(BOOL) preferOn {
NSString *newPreference = preferOn ? #"on" : #"off";
[[NSUserDefaults standardUserDefaults] setValue:newPreference
forKey:ONOFF_PREFERENCE_KEY];
[[NSUserDefaults standardUserDefaults] synchronize];
}