How can I write cocoa bindings as code instead of in the Interface Builder?

Question

In my modell got an NSMutableArray that keeps track of a changing number of elements. In my view I got a NSTextField that shows the number of elements. The view gots unarchived from the nib file and alloc/inits the modell. Therefore it knowns about the modell and the contained array.

I established the connection as follows. In the Interface Builder at the textfield I added a Cocoa Binding "path" like this: myModell.myArray.@count. By this I can access the count property (which is a must since the array itself does not change). The binding is based on key-value compliance which I established at the modell so the array can be accessed. But key-value compliance is not part of the questions.

My question: How can I put the binding into the sourcecode and not writing it into the Interface Builder?

Answer 1

With the NSKeyValueBindingCreation protocol. You send something like [someObject bind:@"value" toObject:myModel withKeyPath:@"myArray.@count" options:nil].