Using convert(_:to:) method in swift

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• How can I automate a project developed in Swift?

  How can I automate project developed in Swift?
• Parsing JSON data from an embedded navigation controller table view to a new view controller Swift IOS

  I'm having a navigation controller with a table view and i pulling json data it displays it but i want to parse the data to a new view controller when a table cell is selected it displays a black screen This is the first screen and I want to parse data to a new view when a cell is selected here is part of the code

  func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
      self.selectedEvents = self.events[indexPath.row]
      self.performSegue(withIdentifier: "goToEvent", sender: self)
  }
  
  override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
      if segue.identifier == "goToEvent"  {
          if let navController = segue.destination as? UINavigationController {
              if let chidVC = navController.topViewController as? EventDetailViewController {
                  chidVC.selectedEvents = self.selectedEvents
              }
          }
      }
  }
  

  This is the second view controller and Its what i want to use to parse the json data to. and this is how i'm parsing the data
  

  var selectedEvents: Event?
  override func viewDidAppear(_ animated: Bool) {
      print("Loading")
      if let eve = self.selectedEvents {
  
          self.eventLabel.text = eve.name
          self.locationLabel.text = eve.loca
          self.desclabel.text = eve.desc
          self.dateLabel.text = eve.dat
          self.timeLabel.text = eve.tim
          self.idLabel.text = eve.idd
  
          let width = self.view.frame.size.width
          let height = width/320 * 180
          self.imageLayoutConstraint.constant = height
  
          Alamofire.request((selectedEvents?.banner!)!).responseImage { response in
              debugPrint(response)
              print(response)
              if let image = response.result.value {
                  //cell.eventImage.image = image
                  self.eventImageView.image = image
              }
          }
          Alamofire.request((selectedEvents?.log!)!).responseImage { response in
              if let image = response.result.value {
                  self.eventImageView.image = image
              }
  
          }
  
      }
  }
  
• Error casting variable opening plist file from bundle Cast from 'Data?' to unrelated type '[[String : Any]]' always fails

  I'm opening plist file and trying to cast the variable into an Array [[String: Any]] but I'm getting this error

  "Cast from 'Data?' to unrelated type '[[String : Any]]' always fails"

  Here is my code:

  let myVariable = (try fileManager.contents(atPath: documents) as! [[String: Any]])
  

  My question to you guys is how can I can convert or cast the contents of the plist as an Array?

  I'll really appreciate your help.
• Swizzling Font Descriptors for Storyboards and Nibs

  Is it possible to swizzle the font descriptors that are used in Storyboards and Nibs like you could with code instantiated fonts?

  class func overrideInitialize() {
      guard self == UIFont.self else { return }
  
      if let preferredFontMethod = class_getClassMethod(self, #selector(preferredFont(forTextStyle:))), 
          let myPreferredFontMethod = class_getClassMethod(self, #selector(myPreferredFont(forTextStyle:))) {
          method_exchangeImplementations(preferredFontMethod, myPreferredFontMethod)
      }
  
  }
  
  @objc class func myPreferredFont(forTextStyle style: UIFontTextStyle) -> UIFont {
  
      switch style {
      case UIFontTextStyle.body:
          return UIFont(name: "SomeFontName", size: 17)!
  
      ...
  
      default:
          return UIFont(name: "SomeFontName", size: 17)!
      }
  }
  

  Right now I can successfully swizzle fonts they are used in code but none of my storyboard texts are swizzled.
• Transfer gestures on a UIView to a UITableView in Swift - iOS

  I have a layout with a UIView at the top of the page and, right below it, I have a UITableView.

  What I am wanting to do is to transfer the gesture interactions on the UIView to the UITableView, so when the user makes a drag up/down on the UIView, the UITableView scrolls vertically.

  I tried the following code

  tableView.gestureRecognizers?.forEach { uiView.addGestureRecognizer($0) }
  

  but it removed the gestureRecognizers from the UITableView somehow :/

  ---

  Obs.: the UIView cannot be a Header of the UIScrollView
• Adding an overlay under a UIView in Swift

  I've wanted to add an overlay under UIView. What I want to do is to switch the visibility of a overlay under the UIView and to switch the height of the red view when the red view is tapped. Like this;

  

  

  My code is:

  private static let MIN_HEIGHT: CGFloat = 80
  
  private static let MAX_HEIGHT: CGFloat = 280
  
  @IBOutlet weak private var containerView: UIView!
  @IBOutlet weak private var containerViewHeightConstraint: NSLayoutConstraint!
  
  override func viewDidLoad() {
      super.viewDidLoad()
  
      let controller = SecondViewController()
      controller.view.translatesAutoresizingMaskIntoConstraints = false
      addChildViewController(controller)
  
      containerView.addSubview(controller.view)
      containerView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(containerViewTapped)))
  
      NSLayoutConstraint.activate([
          controller.view.leadingAnchor.constraint(equalTo: containerView.leadingAnchor),
          controller.view.trailingAnchor.constraint(equalTo: containerView.trailingAnchor),
          controller.view.topAnchor.constraint(equalTo: containerView.topAnchor),
          controller.view.bottomAnchor.constraint(equalTo: containerView.bottomAnchor)
      ])
  
      controller.didMove(toParentViewController: self)
  }
  
  @objc private func containerViewTapped(_ gesture: UITapGestureRecognizer) {
      guard let constraint = containerViewHeightConstraint else { return }
      if gesture.state == .ended {
          if constraint.constant == FirstViewController.MIN_HEIGHT {
              UIView.animate(withDuration: 0.7, animations: {
                  constraint.constant = FirstViewController.MAX_HEIGHT
                  self.view.layoutIfNeeded()
              })
          } else {
              UIView.animate(withDuration: 0.7, animations: {
                  constraint.constant = FirstViewController.MIN_HEIGHT
                  self.view.layoutIfNeeded()
              })
          }
      }
  }
  

  How can I do that? Thanks for help.
• Swift - How to resize a UIView based on its UILabel size (that is inside)

  I'm a bit new in Swift, and I need some help with this:

  I have a UILabel inside a UIView, and this label can receive any ammount of text. So I want to resize the UILabel based on the text it receives, and also resizes its container, the UIView. The UILabel must have a max width but not max height. It is very similar to what happens in Whatsapp with a message text (his green container grows accordly the text inside).

  I believe it is about auto layout, but I really can't understand most of it.

  EDIT: Create dynamically.

  Can anyone help me?
• CollectionViewLayout Height

  I want to custom a lot of layout size for each row of my collectionView by using UICollectionViewDelegateFlowLayout like below:

  func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
          let width = view.frame.width
          if indexPath.row == 0 {
              return CGSize(width: width, height: 300)
          }else if indexPath.row == 1 {
              return dynamicSize // i want this size wrap its content
          }
          return CGSize(width: width, height:100)
  }
  

  I want dynamicSize that can wrap its content for some row. Anyone know how to do this?

  Here is image of cell that i want dynamic size to wrap it.

  
• [__NSCFNumber length]: unrecognized selector sent to instance 0xb000000000000113'

  I am trying to display images in collectionView. Getting data from server with 17 images. I took an Array called Imageofarray. I am appending 17 images to array. when I am going to display in collectionView, its showing below exception:

  unrecognized selector sent to an instance

  -(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView
                   cellForItemAtIndexPath:(NSIndexPath *)indexPath
  {
      ProudpartnersViewCell *myCell = [collectionView
                                       dequeueReusableCellWithReuseIdentifier:@"cell"
                                       forIndexPath:indexPath];
      myCell.layer.masksToBounds = NO;
      myCell.layer.shadowRadius = 5;
      myCell.layer.shadowOffset = CGSizeMake(0.0, 3.0);
      myCell.layer.shadowOpacity = 0.2
      NSString *strImg_Path = [[NSString alloc]init];
  
      NSString *arrayResult = [imageOfArray objectAtIndex:indexPath.row];  // error is here
      strImg_Path = [NSString stringWithFormat:@"%@",[NSURL URLWithString:arrayResult]];
      [myCell.proudOfImages sd_setImageWithURL:[NSURL URLWithString:strImg_Path]
                    placeholderImage:[UIImage imageNamed:@"placeholer_image"]];    
      return myCell;
  }
  

  thank you
• TableView cell height not according to collectionview height on first reload

  I know this is already asked in many threads but none of the solutions are working for me. Problem scenario is: I have a collectionview in tableview cell. The constraints on collection view are as: Collectionview top, leading, trailing and bottom constraint to superview and heightconstraint (with priority 999). Changing the height of collection view as:

  func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
      if let cell = collectionView.dequeueReusableCell(withReuseIdentifier: GalleryCollectionViewCell.identifier, for: indexPath) as? GalleryCollectionViewCell {
          collectionViewHeightConstraint.constant = collectionView.contentSize.height
          self.layoutIfNeeded()
          return cell
      }
      return UICollectionViewCell()
  }
  

  On a button click the tableview is reload and when collectionview height constraint value is printed, it comes true but the tableview cell is not getting exact content size. But when i scroll then the tableview cell gets the exact size.

  PS: Also tried using :

  collectionViewHeightConstraint.constant = collectionView.collectionViewLayout.collectionViewContentSize.height
  
• Swift first selected in collection view

  I am trying to get the first selected cell in the collection view. It is showing nil but in the app there is cells showing up. The clientCollectionView is coming up nil too. Here is the function that i am trying to use

  func currentClient() -> Client? {
      let idx = self.clientsCollectionView?.indexPathsForSelectedItems?.first
      guard let firstSelected = idx?.row else {
          return nil
      }
      return clients()[firstSelected]
  }
  
  func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
      return clients().count
  }
  
  func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
      let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "clientCollectionViewCell", for: indexPath)
      if let cell = cell as? ClientCollectionViewCell {
          cell.client = clients()[indexPath.row]
      }
      return cell
  }
  
  func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
      populateExerciseFields()
  }
  
• UICollectionViewCell: expand text with "See More" button - AutoSizing

  I'm using UICollectionView AutoSizing cells with multiple UILabels placed into the UIStackView.

  I need to expand the label and the cell when the user taps on the "See more" button.

  So far, I'm able to update the label, but the update doesn't trigger the UICollectionView to update the cell's size.

  Before the update:

  

  After the update:

  

  Code I tried to update the cell:

    var collapsed = true {
      didSet {
        subtitle.numberOfLines = collapsed ? 2 : 0
        subtitle.invalidateIntrinsicContentSize()
        subtitle.setNeedsLayout()
        subtitle.setNeedsDisplay()
        subtitle.layoutIfNeeded()
      }
    }
  

  layoutSubviews() gets called, but preferredLayoutAttributesFitting(_ layoutAttributes: UICollectionViewLayoutAttributes) -> UICollectionViewLayoutAttributes not.

  I need to trigger the call to the preferredLayoutAttributesFitting(_ layoutAttributes: UICollectionViewLayoutAttributes) -> UICollectionViewLayoutAttributes method.

  Update:

  This "hack" works great:

    func invalidate() {
      guard let collection = superview as? UICollectionView else {return}
      collection.collectionViewLayout.invalidateLayout()
    }
  

  How can I mark only specific cell to be resized?

  Video of the effect I'm trying to achieve
• My UICollectionViewCell item is nil?

  My CollectionViewCell imageView is nil

  My Cell File is here

  class MyTicketsCollectionViewCell: UICollectionViewCell {
  
       @IBOutlet weak var imgTicket: UIImageView!
  }
  

  My Controller File Code is here

  class MyTicketsCollectionViewController: UICollectionViewController {
  
       var photos: [String] = ["ticket1","ticket2","ticket3","ticket4"]
  
       override func viewDidLoad() {
       super.viewDidLoad()
  
           self.collectionView?.register(MyTicketsCollectionViewCell.self, forCellWithReuseIdentifier: "MyTicketsCollectionViewCell")
  
       }
  
       override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
  
           return photos.count
       }
  
       override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
  
  
           let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "MyTicketsCollectionViewCell", for: indexPath) as! MyTicketsCollectionViewCell
  
           cell.imgTicket.image = UIImage(named: photos[indexPath.row])
  
          return cell
      }
  
  }
  

  Error is "Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value"

  When I debug it then

   cell.imgTicket is nil
  

  How solve this issue?