iPhone App : How to get default value from root.plist?

Question

I am working on an iPhone app

I read a key from root.plist like this :

NSString *Key1Var = [[NSUserDefaults standardUserDefaults] stringForKey:@\"Key         


        

Answer 1

I've translated Mike Weller's solution into Swift 2.0/iOS 9 and made it work for my App:

func registerDefaultsFromSettingsBundle() {
    guard let settingsBundle = NSBundle.mainBundle().URLForResource("Settings", withExtension:"bundle") else {
        NSLog("Could not find Settings.bundle")
        return;
    }

    guard let settings = NSDictionary(contentsOfURL: settingsBundle.URLByAppendingPathComponent("Root.plist")) else {
        NSLog("Could not find Root.plist in settings bundle")
        return
    }

    guard let preferences = settings.objectForKey("PreferenceSpecifiers") as? [[String: AnyObject]] else {
        NSLog("Root.plist has invalid format")
        return
    }

    var defaultsToRegister = [String: AnyObject]()
    for var p in preferences {
        if let k = p["Key"] as? String, v = p["DefaultValue"] {
            NSLog("%@", "registering \(v) for key \(k)")
            defaultsToRegister[k] = v
        }
    }

    NSUserDefaults.standardUserDefaults().registerDefaults(defaultsToRegister)
}

Answer 2

See this question for a complete solution.

You essentially want to run this code before accessing the setting:

- (void)registerDefaultsFromSettingsBundle {
    NSString *settingsBundle = [[NSBundle mainBundle] pathForResource:@"Settings" ofType:@"bundle"];
    if(!settingsBundle) {
        NSLog(@"Could not find Settings.bundle");
        return;
    }

    NSDictionary *settings = [NSDictionary dictionaryWithContentsOfFile:[settingsBundle stringByAppendingPathComponent:@"Root.plist"]];
    NSArray *preferences = [settings objectForKey:@"PreferenceSpecifiers"];

    NSMutableDictionary *defaultsToRegister = [[NSMutableDictionary alloc] initWithCapacity:[preferences count]];
    for(NSDictionary *prefSpecification in preferences) {
        NSString *key = [prefSpecification objectForKey:@"Key"];
        if(key) {
            [defaultsToRegister setObject:[prefSpecification objectForKey:@"DefaultValue"] forKey:key];
        }
    }

    [[NSUserDefaults standardUserDefaults] registerDefaults:defaultsToRegister];
    [defaultsToRegister release];
}

This will load the default values into the standardUserDefaults object so you will no longer get back nil values, and you don't have to duplicate the default settings in your code.

Answer 3

I do this early after launch, before I try to get my settings:

    userDefaultsValuesPath=[[NSBundle mainBundle] pathForResource:@"UserDefaults"
                                                           ofType:@"plist"];
    userDefaultsValuesDict=[NSDictionary dictionaryWithContentsOfFile:userDefaultsValuesPath];

    // set them in the standard user defaults
    [[NSUserDefaults standardUserDefaults] registerDefaults:userDefaultsValuesDict];

    if (![[NSUserDefaults standardUserDefaults] synchronize])
        NSLog(@"not successful in writing the default prefs");

Answer 4

In my application delegate, I override the +initialize method and register new application default preferences.

For example:

+ (void) initialize {
    if ([self class] == [MyAppDelegate class]) {        
        // initialize user defaults dictionary
        BOOL isFirstTimeRun = YES;
        BOOL isKeychainTurnedOn = NO;
        BOOL isSSLTurnedOn = YES;
        NSString *testURLString = @"http://stackoverflow.com";
        NSMutableDictionary *resourceDict = [NSMutableDictionary dictionary];
        [resourceDict setObject:[NSNumber numberWithBool:isFirstTimeRun] forKey:kIsFirstTimeRunKey];
        [resourceDict setObject:[NSNumber numberWithBool:isKeychainTurnedOn] forKey:kIsKeychainTurnedOnKey];
        [resourceDict setObject:[NSNumber numberWithBool:isSSLTurnedOn] forKey:kIsSSLTurnedOnKey];
        [resourceDict setObject:testURLString forKey:kTestURLString];
        [[NSUserDefaults standardUserDefaults] registerDefaults:resourceDict];
    }
}

Answer 5

A Swift 3 version based on Mike Weller's original solution if anyone needs it:

static func registerDefaultsFromSettingsBundle() {

    guard let settingsBundle = Bundle.main.url(forResource: "Settings", withExtension: "bundle") else {
        print("Could not find Settings.bundle")
        return
    }
    guard let settings = NSDictionary(contentsOf: settingsBundle.appendingPathComponent("Root.plist")) else {
        print("Couldn't find Root.plist in settings bundle")
        return
    }

    guard let preferences = settings.object(forKey: "PreferenceSpecifiers") as? [[String: AnyObject]] else {
        print("Root.plist has an invalid format")
        return
    }

    var defaultsToRegister = [String: AnyObject]()
    for var p in preferences {
        if let k = p["Key"] as? String, let v = p["DefaultValue"] {
            print("Registering " + v.debugDescription + " for key " + k)
            defaultsToRegister[k] = v as AnyObject
        }
    }

    UserDefaults.standard.register(defaults: defaultsToRegister)
}

Answer 6

Here is the code I use in iOS 7, based heavily on Mike Weller's code above.

Put this method in your AppDelegate.m:

- (void)registerDefaultsFromSettingsBundleWithPlist:(NSString *)plist {
NSString *settingsBundle = [[NSBundle mainBundle] pathForResource:@"Settings" ofType:@"bundle"];
if(!settingsBundle) {
    NSLog(@"Could not find Settings.bundle");
    return;
}
NSString *bundle = [NSString stringWithFormat:@"%@.plist",plist];
NSDictionary *settings = [NSDictionary dictionaryWithContentsOfFile:[settingsBundle stringByAppendingPathComponent:bundle]];
NSArray *preferences = [settings objectForKey:@"PreferenceSpecifiers"];

NSMutableDictionary *defaultsToRegister = [[NSMutableDictionary alloc] initWithCapacity:[preferences count]];
for(NSDictionary *prefSpecification in preferences) {
    NSString *key = [prefSpecification objectForKey:@"Key"];
    if(key) {
        [defaultsToRegister setObject:[prefSpecification objectForKey:@"DefaultValue"] forKey:key];
    }
}

[[NSUserDefaults standardUserDefaults] registerDefaults:defaultsToRegister];
//[defaultsToRegister release];
}

And then call it for every settings file you're using (for nested settings), from some place early in your code like didFinishLaunchingWithOptions:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
//register default settings into NSUserDefaults
    @try {
        [self registerDefaultsFromSettingsBundleWithPlist:@"Root"];
        [self registerDefaultsFromSettingsBundleWithPlist:@"Chat"];
        [self registerDefaultsFromSettingsBundleWithPlist:@"IVR"];
        [self registerDefaultsFromSettingsBundleWithPlist:@"Video"];
    }
    @catch (NSException * e) {
        NSLog(@"Exception: %@", e);
        NSLog(@"Try adding the Default Value field to each preference item in the Settings.bundle plist files.");
    }
    @finally {

    }
    ...