Passing array to another class - Objective C

I manage to pass the following array from MessagesTableViewController.m to arraySelectedCategory in another clas开发者_如何学运维s called MessageDetailViewController.m:

self.messageDetailViewController.arraySelectedCategory =
        [[NSMutableArray alloc] initWithObjects:@"Value 1",@"Value 2", @"Value 3", nil];

but how do I hand over an array stored in: NSMutableArray *categories;

self.messageDetailViewController.arraySelectedCategory = ?????

Thanks!

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I take it that you want a copy of the categories array?

self.messageDetailViewController.arraySelectedCategory = [categories copy];

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You can use NSUserDefaults. The value can be used in whole program.