Access an NSUserDefault from multiple views - ios

Question

I am trying to access an NSUserDefault called prefs from multiple views. I am allocating prefs in one view but I don't know how to access it without just reallocating a new NSUserDefault in the second view.
Also, my operating system is ios.
Here is my FlipSideViewController Function:
The function in my FlipSideViewController: 'NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
- (IBAction) changeRate:(id)sender {
if (rate.selectedSegmentIndex == 1){
[prefs setInteger:1 forKey:#"myRate"];//save
}
else if (rate.selectedSegmentIndex == 2){
[prefs setInteger:2 forKey:#"myRate"];//save
}
[[NSUserDefaults standardUserDefaults] synchronize];
};
And this is the MainViewController function:
NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
// [prefs setValue: #"0" forKey: #"myRate"];
if (!([prefs valueForKey: #"myRate"])){
[prefs setInteger:0 forKey: #"myRate"];
}
[prefs setInteger:2 forKey: #"myRate"];
int rateOption = [[prefs valueForKey: #"myRate"] intValue];
if (rateOption == 1)
{
dayOrHourly.text = #"% of Day:";
percentOrHours.hidden = YES;
hours.hidden = YES;
dayPercentage.hidden = NO;
}
else if (rateOption == 2)
{
dayOrHourly.text = #"# of Hours:";
percentOrHours.hidden = NO;
dayPercentage.hidden = YES;
}

Answer 1

Having more than one prefs for different views shouldn't be a problem. Just call
[prefObject synchronize];
when you modify one of the instances of NSUserDefaults in one view or try to access them from another view and you'll be fine.
But if you really want to keep a single object shared across all your view controllers, put it in your App Delegate. [I must say, I don't see the point...]

Answer 2

NSUserDefaults is a singleton class. You're not allocating instances of it, you're accessing it.
That said, have you tried using objectForKey instead of valueForKey? Values can't return values, (... valueForKey] intValue];) whereas objects do indeed return values.
Additionally, here's how I'd do it.
First, I'd define a constant in a global header, like so:
#define kSettings [NSUserDefaults standardUSerDefaults];
Then, you should be just fine accessing NSUserDefaults across views:
[kSettings setObject:#"This is a test." forKey:#"TestString"];
to read out the string, you would do this:
[kSettings objectForKey:#"TestString"];
I suggest defining some "global constants" for accessing objects stored in NSUserDefaults. For example:
#define kTestString [kSettings objectForKey:#"TestString"];