Question

The Question is this :

I have a view controller Controller 1 which is a delegate of 2 other controllers Controller 2 and Controller 3.

Controller 2 has a delegate method called “FOO”, Controller 3 has the same method.

Can I implement one “FOO” method inside Controller 1 if both “FOO” methods tells the delegate to do the same exact thing ?

Thanks

Shani

Answer 1

Good delegate design means methods shouldn’t have the same name. For example, if I have two classes called FooA and FooB, that both perform the delegating action foobar:(BOOL)force, then the delegate method names should be as follows:

- (void)fooA:(FooA*)foo foobar:(BOOL)force;
- (void)fooB:(FooB*)foo foobar:(BOOL)force;

This way, your ‘Controller 1’ will be able to differentiate between the two delegate methods. You will notice this in other delegates, for example UITableView:

- (BOOL)tableView:(UITableView *)tableView shouldHighlightRowAtIndexPath:(NSIndexPath *)indexPath

You’re able to differentiate if shouldHighlightRowAtIndexPath originated from a UITableView or a different class.

Saying this, it is entirely possible to have a single method name shared between two delegates, it’s just the delegate won’t be sure of the source of the delegation.