What is tableView delegate?
func tableView(UITableView, willDisplay: UITableViewCell, forRowAt: IndexPath) Tells the delegate the table view is about to draw a cell for a particular row. func tableView(UITableView, indentationLevelForRowAt: IndexPath) -> Int. Asks the delegate to return the level of indentation for a row in a given section.
What class does UITableView inherit from?
TableView can be defined as the view which can arrange the data using rows in a single column. It is used in almost every iOS application, for example, contacts, facebook, Instagram, etc. The tableview is the instance of the UITableView class, which inherits the UIScrollView class.
What is UITableView in Swift?
A view that presents data using rows in a single column. iOS 2.0+ iPadOS 2.0+ Mac Catalyst 13.1+ tvOS 9.0+
What are delegate and datasource methods of UITableView?
Datasource methods are used to generate tableView cells,header and footer before they are displaying.. Delegate methods provide information about these cells, header and footer along with other user action handlers like cell selection and edit..
What is difference between delegate and datasource in iOS?
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.
How do you work with Uitableview?
- Step 1: Create a ViewController with a TableView.
- Step 2: Create a Custom Cell.
- Step 3: Embed in Navigation Controller.
- Step 4: Create the Detail View Controller.
- Step 5: Setup the Detail View Controller Outlets and Variables.
- Step 6: Create a Segue from the Cell to the Detail ViewController.
- Step 7: Pass the Data.
What is the difference between UITableView and UICollectionView?
Tableiw is a simple list, which displays single-dimensional rows of data. It’s smooth because of cell reuse and other magic. 2. UICollectionView is the model for displaying multidimensional data .
What is a UITableView?
UITableView is a subclass of UIScrollView that allows users to scroll the table vertically (the closely-related UICollectionView class allows for horizontal scrolling and complex two-dimensional layouts). The table consists of UITableViewCell objects that are used to render the rows of the table.
How do you work with UITableView?
Is UITableViewDataSource a delegate?
UITableViewDelegate and UITableViewDataSource are two delegate protocols that let us tell the table view how to behave. Delegates allow an object to delegate responsibility and decision-making to other parts of your app.
Why we use delegates 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.
What is the difference between delegate and protocol in Swift?
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 is swift UICollectionView?
An object that manages an ordered collection of data items and presents them using customizable layouts.
What is a delegate in Swift?
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.
Why delegates are weak in Swift?
Why delegate should be weak var? Before you begin I highly recommend you to check ARC story. We will design protocol and classes in order to show retain cycle on delegates. With using lazy keyword we are not initializing delegate which means there is no memory leak right now.
What is the difference between delegate and callback?
The calling class has a preferred function that it wants run called a callback. The calling class sets the delegate to it’s callback. The difference between a delegate and a callback is the perspective: The service class calls the delegate that is set to the calling classes callback.
Can delegation be implemented without a protocol?
You don’t have to use protocols…but you should if you want to keep things flexible. Delegation is in essence asking someone else to do something for you. If you enforce a contract, then its more likely they will do it for you.
What is the purpose of delegate in Swift?
What is the difference between Uitableview and UICollectionView?
What is Uicollectionviewlayout?
An abstract base class for generating layout information for a collection view.
Why We Use delegate in iOS?
The delegating object keeps a reference to the other object and at the suitable time sends a message to it. The delegate may respond to the message by updating the appearance or state of itself or other objects in the application and in some cases it can return a value that affects how an imminent event is handled.
Why delegate is never retained?
The rule is to not retain it because it’s already retained elsewhere and more important you’ll avoid retain cycles.
Are delegates callbacks?
Delegates are the idiomatic way of implementing callbacks in . NET – but you don’t have to. You could use an interface, for example. (In particular you could then have one callback with one method to call on error, and one on success.
Is callback a delegate?
What is the difference between delegate and notifications?
use delegates when you want the receiving object to influence an action that will happen to the sending object. use notifications when you need to inform multiple objects of an event.