NSUserDefaults for self created classes - objective-c

Question

I'm having a problem in a usually very simple quest, I want to create a custom class containing an integer, a NSString and a NSDate. However, in my example I only use a NSString to show my problem when storing objects.
This is my class header:
#import
#interface MyClass : NSObject <NSCoding> {
NSString * myString;
}
#property (retain) NSString * myString;
#end
and my body:
#import "MyClass.h"
#implementation MyClass
#synthesize myString;
- (id)initWithCoder:(NSCoder *)coder {
self = [super init];
if (self) {
myString = [coder decodeObjectForKey:#"myString"];
}
return self;
}
- (id)init {
self = [super init];
if (self) {
myString = #"Hi";
}
return self;
}
- (void)encodeWithCoder:(NSCoder *)aCoder{
[aCoder encodeObject: myString forKey:#"myString"];
}
- (void)dealloc {
myString = nil;
[super dealloc];
}
#end
My ViewController contains two buttons called Create and Read, as well as a UILabel called label.
#import <UIKit/UIKit.h>
#interface UserDefaultsTestViewController : UIViewController {
IBOutlet UILabel *label;
}
- (IBAction)pushCreate;
- (IBAction)pushLoad;
#end
I will only show the functions I've edited here:
#import "UserDefaultsTestViewController.h"
#import "MyClass.h"
- (IBAction)pushCreate {
MyClass * myClass = [[MyClass alloc] init];
NSData * data = [NSKeyedArchiver archivedDataWithRootObject:myClass];
NSUserDefaults * defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:data forKey:#"Test"];
[myClass release];
}
- (IBAction)pushLoad {
NSUserDefaults * defaults = [NSUserDefaults standardUserDefaults];
NSData * atchive = [defaults objectForKey:#"Test"];
MyClass * myClass = [NSKeyedUnarchiver unarchiveObjectWithData:atchive];
label.text = myClass.myString;
}
However, if I run my code, I get either a EXC_BAD_ACCESS error or it displays it correctly the first time and crashes when doing it a second time, again with the same error.
What am I doing wrong?

Answer 1

You want to do:
self.myString = #"Hi";
Or:
myString = #"Hi";
[myString retain];
Likewise, your dealloc should have:
self.myString = nil;
or
[myString release];