What is protocol and delegate in Swift?

What is protocol and delegate in Swift?

Delegation can be used to respond to a particular action, or to retrieve data from an external source without needing to know the underlying type of that source. Apple notes that: A protocol defines a blueprint of methods, properties, and other requirements that suit a particular task or piece of functionality.

What is difference between protocol and delegate in Swift?

We can say Protocol as a set of rules. That rules can be optional or required like we have to use in protocol. Delegates is a message passing technique in objective C and swift. An object has to take care of that message.

How do I use delegates in Swift?

Key Steps to Delegation

1. Create a delegate protocol that defines the messages sent to the delegate.
2. Create a delegate property in the delegating class to keep track of the delegate.
3. Adopt and implement the delegate protocol in the delegate class.
4. Call the delegate from the delegating object.

What is delegate design pattern in Swift?

The delegate design pattern is a relatively easy way to communicate between two objects through a common interface, protocol in Swift.

Why do we use delegates in Swift?

Delegation is used for everything from handling table view events using UITableViewDelegate , to modifying cache behavior using NSCacheDelegate . The core purpose of the delegate pattern is to allow an object to communicate back to its owner in a decoupled way.

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.

Why Delegates are used in Swift?

WHAT IS protocols in Swift?

Protocols provide a blueprint for Methods, properties and other requirements functionality. It is just described as a methods or properties skeleton instead of implementation. Methods and properties implementation can further be done by defining classes, functions and enumerations.

Why we use delegates in Swift?

What is an OBJ C delegate?

An Objective-C delegate is an object that has been assigned to the delegate property another object. To create one, you define a class that implements the delegate methods you’re interested in, and mark that class as implementing the delegate protocol.

Which is the best way to delegate in Swift?

Using delegate protocols provide a familiar and solid pattern that is a good default for many use cases. Closures add more flexibility, but can also lead to more complicated code (not to mention accidental retain cycles if the delegating object ends up capturing its owner in one of its closures).

When to use Swift delegation in iOS development?

Written by Reinder de Vries on August 5 2020 in App Development, iOS, Swift Delegation, also known as the Delegate pattern, is frequently used in practical iOS development. It’s a must-have in your iOS developer’s toolbox, and today we’re going to figure out how delegation works.

How are events delegated in a delegate protocol?

When you look at these three delegate protocols, you quickly see one common pattern: Every one of the events that are delegated are initiated by a class outside your control, the user, the operating system or its hardware. GPS coordinates are provided by the GPS chip, and are delegated to your code whenever the chip has a fix on a GPS position

What does the uitableviewdelegate do in Swift?

The UITableView class uses the UITableViewDelegate and UITableViewDataSource protocols to manage table view interaction, displaying cells, and changing the table view layout The CLLocationManager uses the CLLocationManagerDelegate to report location-related data to your app, such as an iPhone’s GPS coordinates