What is protocol and delegate in Objective-C?

What is protocol and delegate in Objective-C?

Protocols and Delegates are two related but different concept: A Protocol is a interface a class can conforms to, meaning that class implements the listed methods. A Delegate is typically an anonymous object that conforms to a protocol. The application of Delegate called Delegation is a design pattern.

How do you write a protocol in Objective-C?

In Objective-C, protocols are declared with the “@protocol” keyword. Below is an example of declaring a protocol containing one required method. In Swift, the syntax is a little different but the idea is the same. In Objective-C, you add the protocol name in angle brackets beside the class interface declaration.

What is the difference between delegate and DataSource?

A data source is almost identical to a delegate. The difference is in the relationship with the delegating object. Instead of being delegated control of the user interface, a data source is delegated control of data.

What is Delegation in Xcode?

Delegation provides a way for your custom object to communicate application-specific behavior to the off-the-shelf object. The programming mechanism of delegation gives objects a chance to coordinate their appearance and state with changes occurring elsewhere in a program, changes usually brought about by user actions.

What is Delegation in C?

Advertisements. C# delegates are similar to pointers to functions, in C or C++. A delegate is a reference type variable that holds the reference to a method. The reference can be changed at runtime. Delegates are especially used for implementing events and the call-back methods.

What is delegate in iOS Objective-C?

A delegate is an object that acts on behalf of, or in coordination with, another object when that object encounters an event in a program. The delegating object is often a responder object—that is, an object inheriting from NSResponder in AppKit or UIResponder in UIKit—that is responding to a user event.

What is the difference between delegate and protocol?

Protocol is a set of methods (either optional or required) that would be implemented by the class which conforms to that protocol. While, delegate is the reference to that class which conforms to that protocol and will adhere to implement methods defined in protocol.

What are the methods of delegation?

9 Delegation Tips for Managers

  • Know What to Delegate. Not every task can be delegated.
  • Play to Your Employees’ Strengths and Goals.
  • Define the Desired Outcome.
  • Provide the Right Resources and Level of Authority.
  • Establish a Clear Communication Channel.
  • Allow for Failure.
  • Be Patient.
  • Deliver (and Ask For) Feedback.

What is delegate in Swift with example?

The Delegate Pattern in Swift In Swift, a delegate is a controller object with a defined interface that can be used to control or modify the behavior of another object. One example is the UIApplicaitonDelegate in an iOS app.

What is delegation with example?

When a group of steel workers are assigned to represent all steel workers in union talks, this group is an example of a delegation. When a boss assigns tasks to his employees, this is an example of delegation.