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Alex Atwater
2,624 Points"Instance Method"
In Objective-C the teacher keeps saying "Instance Method". For example:
-(type)instanceMethodWithParam1:(param1Type)param1Name
That's like the "skeleton" he gave us of the syntax of an "Instance Method" in objective-c. So what is an instance method exactly?! What else could it be, meaning what if that "-" wasn't there?
2 Answers
John W
21,558 PointsWhen you declare a variable with a class, let's say NSString * aString = @"hello world!"; you are declaring an instance of the class. An instance method is thus a method that is called with that particular instance, or copy, of the class you created. You can imagine a class declaration being the blueprint and the instance being the actual car that is built from it. When you push the gas pedal, you are causing that particular copy of the car to move. Thus the action of pushing the gas pedal is an instance method, since it interacts only with that single copy and not the blueprint itself.
As Justin stated, there is also class method, which is declared by preceding the declaration with + instead of -. A class method is used with the class itself instead of the declared variable/copy/instance of the class.
Justin Johnson
Courses Plus Student 24,793 Pointsa + sign before the return type can indicate that it is a class method.