Saving NSRect to NSUserDefaults

Question

Currently I'm trying to save an NSRect to my user defaults. Right now I'm using a NSValue to wrap it as an object then save it into the user defaults as an object with the following code

[userDefaults setObject:[NSValue valueWithRect:rect forKey:@"Key"]];

However, when I run it, I get an error that says [NSUserDefaults setObject:forKey:]: Attempt to insert non-property value 'NSRect: {{0, 0}, {50, 50}}' of class 'NSConcreteValue'.

Does anyone know how I can fix this? Thanks.

Answer 1

Here is a much simpler solution, using NSString:

// store:
[[NSUserDefaults standardUserDefaults] 
   setValue:NSStringFromCGRect(frame) forKey:@"frame"];

// retrieve:
CGRect frame = CGRectFromString(
   [[NSUserDefaults standardUserDefaults] stringForKey:@"frame"]);

Swift 4

// store
UserDefaults.standard.set(NSStringFromCGRect(rect), forKey: "frame")

// retrieve
if let s = UserDefaults.standard.string(forKey: "frame") {
   let frame = CGRectFromString(s)
}

Answer 2

NSValue is not supported by the user defaults.

The value parameter can be only property list objects: NSData, NSString, NSNumber, NSDate, NSArray, or NSDictionary. For NSArray and NSDictionary objects, their contents must be property list objects.

You need to archive the value into data then unarchive it when you access it.

NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
NSRect rect = { 0, 0, 10, 20 };
NSValue *value = [NSValue valueWithRect:rect];

NSData *data = [NSKeyedArchiver archivedDataWithRootObject:value];
[userDefaults setObject:data forKey:@"key"];
[userDefaults synchronize];

data = [userDefaults objectForKey:@"key"];
NSValue *unarchived = [NSKeyedUnarchiver unarchiveObjectWithData:data];
NSLog(@"%@", unarchived);