Property in Swift - Computed property | Property Observers (WillSet & DidSet)

   Computed property -  Computed properties are part of a property type in Swift.  Stored properties are the most common which save and return a stored value  Computed properties calculate (rather than store) a value. A computed property provides a getter and an optional setter to indirectly access other properties and values. Computed property in swift is an interesting topic as you can write code inside a property in swift. Computed properties are provided by classes, structures, and enumerations but stored properties are provided only by classes and structures. This computed property swift tutorial has some tips on how to use the computed property in the right way and avoid the common mistakes that swift programming beginners do while computed property. Example :- Computed property A Calculate Simple Intrest struct CalculateLoan {      var amount : Int      var rate : Int      var years : Int      var simpleInterest: Int {          get {              return ( amount * rate
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Move up textfield when keyboard appears on UIViewController in Swift



Move up textfield when keyboard appears on UIViewController in Swift

 import UIKit
import Foundation
import Alamofire

class ViewController: UIViewController, UIScrollViewDelegate, UITextFieldDelegate {
    
    @IBOutlet weak var scrollViewBottonConstraint: NSLayoutConstraint!
    @IBOutlet weak var emailTextField: UITextField!
    @IBOutlet weak var passwordTextfield: UITextField!
    
    @IBOutlet weak var scrollView: UIScrollView!
    
    
    override func viewDidLoad() {
        super.viewDidLoad()
        scrollView.contentSize = view.frame.size
        let tabGesture = UITapGestureRecognizer(target: self, action: #selector(didTapView(gesture:)))
        view.addGestureRecognizer(tabGesture)
    }
    
    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
        addObservers()
    }
    override func viewDidDisappear(_ animated: Bool) {
        super.viewDidDisappear(animated)
        removeObservers()
    }
    
    @objc func didTapView(gesture: UITapGestureRecognizer){
        
        view.endEditing(true)
    }
    
    func addObservers(){
        let notificationCenter = NotificationCenter.default
        notificationCenter.addObserver(self, selector: #selector(keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
        
        notificationCenter.addObserver(self, selector: #selector(keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
    }
    
    func removeObservers() {
        NotificationCenter.default.removeObserver(self)
    }
    
    @objc func keyboardWillShow(notification: Notification){

        guard let userInfo = notification.userInfo, let frame = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue else {
            return
        }
        let conntentInset = UIEdgeInsets(top: 0, left: 0, bottom: frame.height, right: 0)
        scrollView.contentInset = conntentInset
    }
    @objc func keyboardWillHide(notification: Notification){
        scrollView.contentInset = UIEdgeInsets.zero
    }
    
    func textFieldShouldReturn(_ textField: UITextField) -> Bool
    {
        textField.resignFirstResponder()
        return true
    }
    override func didReceiveMemoryWarning()
    {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
}

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