IOS PROGRAMMING

// frequently ask in Interview var variableOne = 10 var variableTwo = 15 func swapValues(vOne : Int , vTwo : int) -> vOne , vTwo {     vOne ^= vTwo     vTwo ^= vOne     vOne ^= vTwo     return vOne, vTwo }

import UIKit import MessageUI class ViewController: UIViewController, MFMailComposeViewControllerDelegate {    override func viewDidLoad()    {         super.viewDidLoad()         sendEmail()            }    override func didReceiveMemoryWarning()    {         super.didReceiveMemoryWarning()    }    func sendEmail()    {       let mailVC = MFMailComposeViewController()       mailVC.mailComposeDelegate = self       mailVC.setToRecipients([])       mailVC.setSubject("Subject for email")       mailVC.setMessageBody("Email message string", isHTML: false)       presentViewController(mailVC, animated: true, completion: nil)     }     // MARK: - Email Delegate     func mailComposeController(controller: MFMailComposeViewController, didFinishWithResult result: MFMailComposeResult, error: NSError?) {         controller.dismissViewControllerAnimated(true, completion: nil)     } }

import UIKit class ViewController: UIViewController {     var counter = 0     var timer = Timer()     @IBOutlet weak var label: UILabel!     // start timer     @IBAction func startTimerButtonTapped(sender: UIButton) {         timer.invalidate() // just in case this button is tapped multiple times         // start the timer         timer = Timer.scheduledTimer(timeInterval: 0.5, target: self, selector: #selector(timerAction), userInfo: nil, repeats: true)     }     // stop timer     @IBAction func cancelTimerButtonTapped(sender: UIButton) {         timer.invalidate()     }     // called every time interval from the timer     func timerAction() {         counter += 1         label.text = "\(counter)"     }

@IBOutlet var myTextFiled : UITextFiled! override func viewDidLoad()     {         let tapGesture = UITapGestureRecognizer(target: self, action: #selector(self.dismissKeyboard (_:)))         tapGesture.cancelsTouchesInView =                                                                               false              self.view.addGestureRecognizer                                                                 (tapGesture) }     @objc func dismissKeyboard (_ sender: UITapGestureRecognizer) {         myTextFiled.resignFirstResponder()     }

let datepicker = UIDatePicker() func CreateDatePicker()     {         datepicker.datePickerMode = .date         UserDOB.inputView = datepicker         let toolbar = UIToolbar()         toolbar.sizeToFit()         let doneButton = UIBarButtonItem(barButtonSystemItem:.done,target:nil,action:#selector(doneProcess))         doneButton.setTitleTextAttributes([NSAttributedStringKey.foregroundColor : UIColor(rgb: 0xC5949E)], for: .normal)         toolbar.setItems([doneButton], animated: false)                  UserDOB.inputAccessoryView = toolbar     }          // date pickr done button     @objc func doneProcess()     {         let dateformatter = DateFormatter()         dateformatter.dateStyle = .medium         dateformatter.timeStyle = .none         dateformatter.dateFormat = "dd-MM-yyyy"                  UserDOB.text = dateformatter.string(from: datepicker.date)         self.view.endEditing(true)     }

Set info.plist :-  <key>NSPhoto</key> <string> give parmition to access Photo library</string> Delegate :-  UINavigationControllerDelegate, UIImagePickerControllerDelegate @IBOutlet var myImageView: UIImageView! let image = UIImagePickerController() Override func viewDidLoad() {  super.viewDidLoad()   openPhotoLibrary() } // Function for open photo library for your simulator func openPhotoLibrary() {   image.delegate = self  image.navigationController?.navigationBar.isTranslucent = true         image.sourceType = UIImagePickerControllerSourceType.photoLibrary         image.allowsEditing = false         image.mediaTypes = UIImagePickerController.availableMediaTypes(for: .photoLibrary)!                  // Image picker controller cancel button         let myview = UIView()         myview.frame = CGRect(x: 0, y: 0, width: UIScreen.main.bounds.size.width, height: 44)         myview.backgroundColor = UIColor(red: 204.0/255.0, green

Ceate one new class give that name is like this and copy that code in side that file import UIKit class APIConnection: NSObject,URLSessionDelegate {     class var sharedInstance: APIConnection {         struct Static {             static var onceToken: Int = 0             static var instance = APIConnection()         }         return Static.instance     }       func PostResponseFrom(strUrl:String ,Parameter:NSMutableDictionary, completionHandler:@escaping (_ result:Any, _ status:Bool, _ statusCode:CLong)->Void ) -> ()     {         let configuration = URLSessionConfiguration.default         let session = URLSession(configuration: configuration, delegate: self, delegateQueue: OperationQueue.main)               let postUrl = URL(string: strUrl)               let Request = NSMutableURLRequest(url: postUrl!, cachePolicy: .useProtocolCachePolicy, timeoutInterval: 60)         Request.addValue("application/json", forHTTPHeaderField: "Content-Type&q