Question

I have a Class for handling my data in my project, and now I need to store the data.
I’d like to use a Plist but I’m a bit unsure of how to start.
My class is pretty simple – 6 pieces of data, flat (no hierarchy).

I want my app to start with no data, so can I assume that I should create the PList programmatically once the User creates their first piece of data? (That is, don’t create a .plist file in ‘Supporting Files’ prior to distribution?)

Then, when the app starts the next time, read the data and create an NSMUtableArray array of Class instances?

Answer 1

To create a property list, all you need to do is use appropriate types (i.e. those that support the property list format: NSData, NSString, NSDictionary, NSNumber, NSDate, NSArray), store them in a single container, and tell the containing object to write itself to a file. To read the data, you can initialize that same type using a path. For example:

// writing some data to a property list
NSString *somePath = ... // replace ... with the path where you want to store the plist file
NSMutableDictionary myDict = [NSMutableDictionary dictionary];
[myDict setObject:@"Caleb" forKey:@"name"];
[myDict setObject:[NSNumber numberWithInt:240] forKey:@"cholesterolOrIQ"];
[myDict writeToFile:somePath atomically:YES];

// reading the file again
NSDictionary *readDict = [NSDictionary dictionaryWithContentsOfFile:somePath];