NSUserDefaults. setValue works, Not setBool

I trying to store some settings in NSUserDefaults, but It seems that the app won't store the setBool values.

This works:

[[NSUserDefaults standardUserDefaults] setValue: @"hello" forKey: @"test"]; [[NSUserDefaults standardUserDefaults] synchronize];

When I terminate the app and restart it, the value have been saved. However, when I do this:

[[NSUserDefaults standardUserDefaults] setBool: YES forKey: @"test"]; [[NSUserDefaults standardUserDefaults] synchronize]; It won't save after I close the app and restart it.

Should I file a bug report, or is there something I'm missing here?

Thanks

Edit:

I figure what I did wrong. In AppDelegate, I wanted to check if the boolForKey was set, and it it wasn't I did this:

if (![defaults boolForKey: @"test123"])
[defaults setBool: YES forKey: @"test123"];

... however, when it comes to boolWithKey, the "!" just check if the bool is YES or NO, not if its nil.

How can you be sure its not working? I tried your code and it works for me. Are you sure you are reading the Boolean in the correct way AFTER you write it?

This code SHOULD work:

NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setBool:NO forKey:@"test"];

[defaults synchronize];

BOOL myBool = [defaults boolForKey:@"test"];

I had the same problem by having the following code in my AppDelegate to keep track of whether the user had seen a particular viewController to display a walkthrough, and then setting this Bool to NO after the user had seen it.

if (![standardUserDefaults boolForKey:@"firstViewOfVC"]) {
        [standardUserDefaults setBool:YES forKey:@"firstViewOfVC"];
}

But then when you set it to NO later on and check if it "exists", you are actually seeing the NO boolean value and setting it back to yes. The quick fix is just to store the boolean value in an NSNumber object so that you can check for it's existence, independent of its value being YES or NO. See below:

if (![standardUserDefaults objectForKey:@"firstViewOfVC"]){
        [standardUserDefaults setValue:[NSNumber numberWithBool:YES] forKey:@"firstViewOfVC"];
    }

I had the exact same problem. Everything EXCEPT BOOLs were persisting correctly; but i was using some old coding styles from ios 3. recoded this way, everything works.

If anybody else is using old books.... here is an example

Bad stuff:

//////////// set / get bL2R
if (![[NSUserDefaults standardUserDefaults]
      boolForKey:kL2RomanizationChoice]) {
    [[NSUserDefaults standardUserDefaults]
     setBool:YES
     forKey:kL2RomanizationChoice];
    bL2R = YES;
    NSLog(@"L2Rom not found, set to YES.");
}
else {
    bL2R   = [[NSUserDefaults standardUserDefaults]
              boolForKey:kL2RomanizationChoice];
    NSLog(@"L2Rom found.");
    if (bL2R) {
        NSLog(@"L2Rom found to be YES.");
    }

}

Good stuff:

if (![defaults boolForKey:kL2RomanizationChoice])
    [defaults setBool:YES forKey:kL1RomanizationChoice];

L2String_Setting = [defaults objectForKey:kSecondLangChoice];
bL2R = [defaults boolForKey:kL2RomanizationChoice];

Update: sadly this only seemed to work briefly, and now is failing again... using Xcode 4.5.2. may just swap out bools for integers...

XCode 4.6 seems to have the same problem highlighted by hangzhouharry. A useful call is [[NSUserDefaults standardUserDefaults] dictionaryRepresentation] to see if your key values are looking the way they should.

For example -> autoLogout = 0;

which was set as a Bool, [settings boolForKey:@"autoLogout"] returns nothing

[settings integerForKey:@"autoLogout"] returns 0 (as, sort of, expected)

来源：https://stackoverflow.com/questions/9580922/nsuserdefaults-setvalue-works-not-setbool

标签

objective-c

nsuserdefaults