I should subclass NSMutableArray because I had a project which used NSMutableArray (calls) before, but was not thread safe. Anyway, I can't really understand why it would be _really_ better to implement just accessors, but maybe you could explain it a bit more?
On Mar 8, 2012, at 9:02 PM, Charles Srstka wrote: > On Mar 8, 2012, at 8:22 AM, CoGe - Tamas Nagy wrote: > >> Maybe this will helps you, here is my thread-safe subclass of >> NSMutableArray:http://code.google.com/p/cogeopensource/source/browse/trunk/CoGeOpenSource/CoGeThreadSafeMutableArray.m >> >> Works well for my project. > > IMO, if anything is overkill for something like this, it’s subclassing a > mutable array. What you should be doing is implementing accessors to get to > the data stored in the array. If you don’t need an NSMutableArray interface, > you can just implement methods like -objectAtIndex: and > -insertObject:atIndex:, etc. to get at the data, like all of the collection > classes do. If you do need an NSArray interface (for bindings, for example), > then you should implement the KVO indexed accessors, for a few reasons: > > - Using accessors ensures proper encapsulation of your data; you can later > change the implementation under the hood from an NSMutableArray to something > completely different if you desire, without breaking the interface. > > - If you later decide you need to be informed when something changes the > contents of your array, it’s much easier to do with KVO than with vending an > NSMutableArray. > > - It’s generally not a good idea to expose the internal state of your object, > in any case. > > - If you’re planning to use bindings to access this property, you’re going to > want to implement the KVO indexed accessors like objectIn<key>AtIndex:, > insertObject:in<key>AtIndex:, etc. anyway for performance reasons — if you > don’t, the bindings mechanism will basically replace the whole array every > time something changes, by calling the setter for the array. > > - If you really need an NSMutableArray interface to the object’s data, it’s > only one line of code to create an NSMutableArray proxy once the KVO indexed > accessor methods are already implemented, as opposed to adding a whole new > NSMutableArray subclass. > > Charles > _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
