Using convert(_:to:) method in swift

See also questions close to this topic

• Open image enlarge in an Imageview in IOS

  I have used third party lib to show array of images in a slider way. The slider is working fine. Now I'm trying to open the image from a slider to open it in an enlarge image view on tap gesture. I want to open only that image on which user taps. The sepcific index image from an array should be open. I have tried some code but it is giving me error. This is my code,

   int i=0;
  
  tap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(expandImage:)];
  tap.numberOfTapsRequired = 1;
  [_ImageView setUserInteractionEnabled:YES];
  [_ImageView addGestureRecognizer:tap];
  tap = [_imagesData objectAtIndex:i];
  NSLog(@"TTT %@",tap);
  
  [self.view addSubview:_fullImage];
  

  The method is this,

  -(void)expandImage:(UITapGestureRecognizer*)recogniser
  

  { [self.view addSubview:_fullImage];

  UIButton *closeButton = [[UIButton alloc]init];
  [closeButton setTitle:@"Close" forState:UIControlStateNormal];
  

  // [closeButton addTarget:self action:@selector(Closetab) forControlEvents:UIControlEventTouchUpInside]; [_fullImage addSubview:closeButton];

  UIImageView *photoView = [[UIImageView alloc]init];
  [photoView setBackgroundColor:[UIColor blueColor]];
  [_fullImage addSubview:photoView];
  

  // photoView.accessibilityIdentifier = @"nature2.png";

  [_fullImage addSubview:_fullImage];
  

  }
• How to display two textfields euqal space in single tableview cell with equal width, edges space

  I want to display two textfields in single tableview cell along with some separator between of them both. Those, two textfields has equal space to edges and with the separator. I want to create this in programmatically in tableview cell class in Swift language.

  I want this to be fit in all dimension devices.

  Note : I am not using autolayout.

  Any suggestions?
• PortSIP - "DNS Timeout" error on iOS

  We are currently using PortSIP SDK 15.1 (from documentation) for iOS in our project.

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  Is there any configuration or setting we should be looking at in order to further diagnose the issue?
• Debug macOS app inside Parallels vm from host

  I am developing a macOS app that runs on 10.11+. My dev machine runs 10.12 and quite possibly sometime later today 10.13.

  To test the app on 10.11 I copy it into a Parallels virtual machine that runs the older version(s) of macOS. Now if I wanted to actually debug the app under the old system, what would I have to do (Is this even possible)? I had a crash that only happened under 10.11 and it was really hard to debug without having breakpoints available.

  The following problems arise:

  I use Xcode 9 which requires 10.12 afaik, so I can't just run Xcode inside the VM (Aside from the fact that I am specifically building the app with the latest 10.12 SDK, which wouldn't be available on 10.11?).

  So is it possible to actually either

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• How to check values within array of dictionaries without having a key in one line

  I have an array like [[URL: String]] in which I save a random string as value for each URL which is a key in my dictionary. Therefore each key is different.

  I am creating a random string and want to check whether this random string is already in the array or not. For this I am doing:

  let randomString = self.randomString()
  
  for obj in randomStringArray {
      for (key, value) in obj {
          if value != randomString {
              print("not found")
          }
      }    
  }
  

  My question is: Can I write it in one line using functions of array like .filter, .contains or .first etc.?
• Swift UiTableView not reloading search results

  I am having a weird issue where for some reason my UITableView is not being reloading after performing a search. The console prints out the correctly filtered data, but the table simply doesn't change. I have never encountered this issue, so I first attempted the solutions which naturally came to mind:

  1. Tried tableView.reloadData() in the Main Queue

  2. Quit Xcode, clean build, reinstall

  3. Cleared out the derived data dir

  I have found several similar issue in SO, but all of the solutions I've seen are things I've tried, mainly reloading tableview in main queue.

  Hoping maybe I just simply have an issue in my code or something I'm missing.

  I am running Xcode 8.3.3

  import UIKit
  
  class CategoriesViewController: UIViewController {
  
  var isFiltering = false
  var location = Location()
  @IBOutlet weak var tableView: UITableView!
  @IBOutlet weak var searchBar: UISearchBar!
  var categoriesSearchResults = [Category]()
  
  override func viewDidLoad() {
      super.viewDidLoad()
      tableView.delegate = self
      tableView.dataSource = self
      tableView.allowsSelection = true
      tableView.keyboardDismissMode = .onDrag
      let nib = UINib(nibName: "CategoryTableViewCell", bundle: nil)
      self.tableView.register(nib, forCellReuseIdentifier:"CategoryTableViewCell");
      searchBar.returnKeyType = UIReturnKeyType.done
      searchBar.autocapitalizationType = .none
      searchBar.delegate = self
  }
  
  
  extension CategoriesViewController : UITableViewDelegate, UITableViewDataSource {
  
  func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
      return 60
  }
  
  func numberOfSections(in tableView: UITableView) -> Int {
      return 1
  }
  
  func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
      print("HI")
  }
  
  func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
  
      if isFiltering {
          return self.categoriesSearchResults.count
      }
  
      return self.location.categories.count
  }
  
  func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
      let cell = UITableViewCell()
      if let cell = self.tableView.dequeueReusableCell(withIdentifier: "CategoryTableViewCell", for: indexPath) as? CategoryTableViewCell {
          var category: Category
          if isFiltering {
              category = self.categoriesSearchResults[indexPath.row]
          } else {
              category = self.location.categories[indexPath.row]
          }
          cell.name.text = category.name
          cell.status.textColor = UIColor.lightGray
          cell.status.text = "Not Verified"
      }
  
      return cell
  }
  }
  
  extension CategoriesViewController : UISearchBarDelegate {
  
  func searchBarIsEmpty() -> Bool{
      return self.searchBar.text?.isEmpty ?? true
  }
  
  func searchBarSearchButtonClicked(_ searchBar: UISearchBar) {
      self.isFiltering = true
      self.categoriesSearchResults.removeAll()
      tableView.reloadData()
      self.view.endEditing(true)
  }
  
  func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
      if searchBarIsEmpty() {
          self.view.endEditing(true)
          self.isFiltering = false
      } else {
          self.isFiltering = true
          self.categoriesSearchResults = self.location.categories.filter({ (category: Category) -> Bool in
              return category.name.lowercased().contains(searchText.lowercased())
          })
      }
      tableView.reloadData()
  }
  }
  

  and my custom table view cell:

  import UIKit
  
  class CategoryTableViewCell: UITableViewCell {
  @IBOutlet weak var name: UILabel!
  @IBOutlet weak var status: UILabel!
  
  override func awakeFromNib() {
      super.awakeFromNib()
  
  }
  
  override func prepareForReuse() {
      super.prepareForReuse()
      self.name.text   = ""
      self.status.text = ""
  }
  
  override func setSelected(_ selected: Bool, animated: Bool) {
      super.setSelected(selected, animated: animated)
  
      // Configure the view for the selected state
  }
  
  }
  

  Thank you in advance.

  EDIT: Might also be worth mentioning, when I am actively searching, the function tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) is not called??
• Drawing a grid on a UIView in Swift

  I am very new to Swift. Am trying to draw a grid (like a graph page) on a UIView in Swift. The code is running but I don't see any lines. I don't see what I did wrong.

  In the Storyboard I added a View onto the ViewController.

  In code I created a GridView.swift and added it to the View above. Here is the code for GridView class. The function draw is being called and the code running without any errors. Its just doing what I thought it would do.

  Its not even drawing one line (I remove the for loop and just try to draw one line). This seems so basic that it should work.

  import Foundation
  import UIKit
  
  class GridView: UIView 
  {
      fileprivate var gridWidthMultiple: CGFloat
      {
          return 10
      }
      fileprivate var gridHeightMultiple : CGFloat
      {
          return 20
      }
  
      fileprivate var gridWidth: CGFloat
      {   
          return bounds.width/CGFloat(gridWidthMultiple)
      }
  
      fileprivate var gridHeight: CGFloat
      {
          return bounds.height/CGFloat(gridHeightMultiple)
      }
  
      fileprivate var gridCenter: CGPoint {
          return CGPoint(x: bounds.midX, y: bounds.midY)
      }
  
      fileprivate func drawGrid()
      {
          let path = UIBezierPath()
          path.lineWidth = 5.0
  
          for index in 1...Int(gridWidthMultiple) - 1
          {
              let start = CGPoint(x: CGFloat(index) * gridWidth, y: 0)
              let end = CGPoint(x: CGFloat(index) * gridWidth, y:bounds.height)
              path.move(to: start)
              path.addLine(to: end)
          }
      }
  
      override func draw(_ rect: CGRect)
      {
          drawGrid()
      }
  }
  
• Presenting multiple table views inside a container view

  I have a section of my app at the bottom of the screen that pops up when a button is clicked (very much like an action sheet). The container of this popup is a UIView. Inside this UIView, I have embedded a UITableViewCotroller (meaning it is an entire VC of its own that has then been put into this view). When someone clicks on a cell, I want the new view to push into the current view (like normal tableview behaviour). Except, I want the new container to still be inside the master container view. It currently just modally presents the view when a cell is clicked.

  

  As you can see from the picture, the EMBEDED TABLE gets put into the Master Container View and then when a cell is clicked it should push the detail view but still be within the bounds of the master container view.

  Im slightly lost as currently when you click a cell in the embedded table it just pushes a new view controller modally.

  Cheers
• Custom UIView with nib file in Xcode 9

  After updating xCode to 9 version, I noticed the following problem:

  I have custom UIView with cart, which work fine until update. I use this UIView in top navigation item

  This view consist of button and label. And when pressed button, open another view controller

  Then, when I compile app, no action when click button. nothing is happened (no entered to button function).

  In View debugger all looks good: user interaction is On end button is on top layer

  For test I create UIView in simple viewContoller with the same class name and it work. Button open another view controller.

  What could be the problem that it stopped working in navigation item?
• Collection view cell margin bottom between item too large

  Im new to collection view and trying to split the column into 2 equally Im follwing the code from this link to make the column split into 2 Here the link : UICollectionView Set number of columns I manage to split the column into 2 the problem is the margin bottom too large between item.

  

  and heres my code

  class WDProfileFacilitiesCell: UITableViewCell, UICollectionViewDataSource, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout {

  let columnLayout = ColumnFlowLayout(
      cellsPerRow: 2,
      minimumInteritemSpacing: 5,
      minimumLineSpacing: 0,
      sectionInset: UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
  )
  
  @IBOutlet weak var collectionView: UICollectionView!
  @IBOutlet weak var verticalConstraint: NSLayoutConstraint!
  
  var object = ["Wifi", "Free snack", "free toilet", "free services", "Waiting room", "a", "b", "c" ]
  
  override func awakeFromNib() {
      super.awakeFromNib()
      // Initialization code
  
      collectionView.delegate = self
      collectionView.dataSource = self
  
      let nib = UINib(nibName: "FacilitiesCell", bundle: nil)
      self.collectionView.register(nib, forCellWithReuseIdentifier: "facilitiesCell")
  
      self.collectionView.collectionViewLayout = columnLayout
  
  }
  
  func numberOfSections(in collectionView: UICollectionView) -> Int {
      return 1
  }
  
  func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
      return object.count
  }
  
  func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
  
      let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "facilitiesCell", for: indexPath as IndexPath) as! FacilitiesCell
  
      cell.amenitiesLabel.text = object[indexPath.row]
  
      return cell
  }
  
  func collectionView(_ collectionView: UICollectionView, willDisplay cell: UICollectionViewCell, forItemAt indexPath: IndexPath) {
      self.verticalConstraint.constant = self.collectionView.contentSize.height
  }}
  

  As you can see i already set the minimum line spacing to 0 but the margin between wifi and free toilet still big. Any idea why ?
• Can't get items to append in collection view cell from AVPlayer

  I have two UICollectionView cell class, Main Cell and Favorites Cell. The Main cell presents the AVPlayer on selection of cell Items and I wanted to implement same functionality in favorites cell class so I made the Favorites cell class a sub class of the Main Cell. Now, In the AVplayer VC, I have a button for 'add to favorites' which just appends the playing item on the Favorites cell on tap. But after a lot of trial and errors, Its just not appending the item to the cell class. Here is my Main Cell code:

      import UIKit
  
      class MainCell: BaseCell, UICollectionViewDataSource, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout {
  
          lazy var collectionView: UICollectionView = {
              let layout = UICollectionViewFlowLayout()
              let cv = UICollectionView(frame: .zero, collectionViewLayout: layout)
              cv.backgroundColor = UIColor.white
              cv.delegate = self
              cv.dataSource = self
              return cv
          }()
  
          var items: [Item]?
  
          let favoritesCellId = "favoritesCellId"
          let cellId = "cellId"
  
          func parseItems() {
  
              ItemsService.shared.parseItems { (items: [Item]) in
                  self.items = items
                  self.collectionView.reloadData()
              }
          }
  
          override func setupViews() {
              super.setupViews()
  
              parseItems()
  
              addSubview(collectionView)
  
              addConstraintsWithFormat(format: "H:|[v0]|", views: collectionView)
              addConstraintsWithFormat(format: "V:|[v0]|", views: collectionView)
  
              collectionView.register(FavoritesCell.self, forCellWithReuseIdentifier: favoritesCellId)
              collectionView.register(ItemCell.self, forCellWithReuseIdentifier: cellId)
          }
  
          func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
  
              return items?.count ?? 0
          }
  
          func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
  
              let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! ItemCell
              cell.item = items?[indexPath.item]
              cell.backgroundColor = UIColor.white
              return cell
          }
  
          func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
  
              if let item = items?[indexPath.item] {
  
                  showPlayer(item: item)
              }
          }
  
          func showPlayer(item: Item) {
              let playerLauncher = PlayerLauncher()
              playerLauncher.presentPlayer(launcher: playerLauncher)
              playerLauncher.item = item
          }
  

  Here, parseItems() I have added a shared instance of my ItemSerive class where I have parsed all the json data. My code for Favorites Cell class is this:

  import UIKit
  
  class FavoritesCell: MainCell {
  
      override func parseItems() {
  
          NotificationCenter.default.addObserver(self, selector: #selector(handleFavorite), name: Notification.Name(rawValue: "add"), object: nil)
      }
  
      @objc func handleFavorite() {
  
          self.collectionView.reloadData()
  
      }
  }
  

  And finally in the PlayerVC, I have added the Notification for handleFavorite method:

  var isFavorite = false
  
  @objc func handleAddToFavorites() {
  
          if isFavorite {
              addToFavoritesButton.setImage(#imageLiteral(resourceName: "favorites"), for: .normal)
              NotificationCenter.default.post(name: Notification.Name(rawValue: "add"), object: nil)
          } else {
              addToFavoritesButton.setImage(#imageLiteral(resourceName: "add_favorite"), for: .normal)
          }
  
          isFavorite = !isFavorite
      }
  

  Now I have tried calling the Player class in my favoritesCell handleFavorite method, also tried changing the handleFavorite func in favoritesCell to something like:

  @objc func handleFavorite(item: item) {
       self.items.append(item)
       self.collectionView.reloadData()
  }
  

  Then changing the handleFavorites func in Player class to:

  @objc func handleAddToFavorite() {
       if isFavorite {
           addToFavoritesButton.setImage(#imageLiteral(resourceName: "favorites"), for: .normal)
           let favoritesCell = FavoritesCell()
           favoritesCell.handleFavorite(item: item!)
           NotificationCenter.default.post(name: Notification.Name(rawValue: "add"), object: nil)
       }
  }
  

  But nothing worked for me. I tried print the items.count in the favoriteCell class but it is nil even after appedning the item value from Player. How can I append this playing item to my items array in FavoritesCell class and display the cell?
• Align the CollectionView cells with Autolayout for all devices

  I have a problem with constraint on xCode 9. I have an UIVIewController with a UIView that contains an UICollectionView that shows the days of the current month, everything works perfection but I have problems with the cells on the various devices ...

  The collectionView uses paging for cell scrolling

  ---

  Here you see that on iPhone 8 plus it's ok but on iPhone If the cells are cut ..

  I set UICollectionViewFlowLayout for my collectionView but still has problems ... Probably might be the wrong constraint but i can not understand which of these constraints is wrong.

  ---

  Here is the image of the constraint I used for the Custom Cell

  ---

  Here are the constraints of the Custom UIView I have placed in the UIViewController

  

  ---

  I also show you the code I used, maybe the mistake is here

  -(instancetype)initWithCoder:(NSCoder *)aDecoder {
      self = [super initWithCoder: aDecoder];
      if (self) {
  
      }
      return self;
  }
  
  -(void)setupContent:(UIView *)controller {
  
      _arrayWeek = [[NSMutableArray alloc] init];
      _arrayDay = [[NSMutableArray alloc] init];
  
      UICollectionViewFlowLayout *smartLayout = [[UICollectionViewFlowLayout alloc] init];
      _smartCalendar = [[UICollectionView alloc] initWithFrame:self.bounds collectionViewLayout:smartLayout];
  
      //////// Collection View ////////
      _smartCalendar.delegate = self;
      _smartCalendar.dataSource = self;
      _smartCalendar.backgroundColor = [UIColor clearColor];
      _smartCalendar.pagingEnabled = YES;
  
      UINib *nib = [UINib nibWithNibName:@"UDSmartCalendarCell" bundle: nil];
      [_smartCalendar registerNib:nib forCellWithReuseIdentifier:cellID];
  
      _smartCalendar.translatesAutoresizingMaskIntoConstraints = NO;
      [self addSubview:_smartCalendar];
  
       //////// CONSTRAINT COLLECTION VIEW ////////
      [_smartCalendar.trailingAnchor constraintEqualToAnchor:self.trailingAnchor constant:0.0].active = YES;
      [_smartCalendar.topAnchor constraintEqualToAnchor:self.topAnchor constant:0].active = YES;
      [_smartCalendar.widthAnchor constraintEqualToAnchor:self.widthAnchor].active = YES;
      [_smartCalendar.heightAnchor constraintEqualToConstant:60].active = YES;
  
       //////// FLOW LAYOUT COLLECTION VIEW////////
      smartLayout.scrollDirection = UICollectionViewScrollDirectionHorizontal;
      CGFloat width = floorf(_smartCalendar.frame.size.width  / 6);
      smartLayout.itemSize = CGSizeMake(width, 50);
      smartLayout.minimumInteritemSpacing = 3;
      smartLayout.minimumLineSpacing =3;
      smartLayout.sectionInset = UIEdgeInsetsMake(0, 0, 0, 0);
      _smartCalendar.collectionViewLayout = smartLayout;
      _smartCalendar.showsHorizontalScrollIndicator = NO;
  
  
      [self buildSmartCalendarWithWeekArray:_arrayWeek andDay:_arrayDay];
      [self scrollToItemToday];
  
  }
  
• This is only one cell regardless of how many photos I have got from Flickr, and I can’t save these photos

  No matter how many photos I have gotten from Flickr, there is only one cell in the collectionView.

  func loadPhotos(pageNumber: Int) {
      GetImageUrls.sharedInstance.getImageUrls(latitude: latitude!, longitude: longitude!, pageNumber: pageNumber){(success, photosUrl, error) in
          if success {
  
              print("photosUrl number is \(photosUrl?.count) ")
              for url in photosUrl! {
                  let photo = Album(location: self.tappedPinLocation!, imageUrl: url, context: self.stack.context)
                  print("photo is \(photo)")
              }
              do {
                  try self.stack.context.save()
                  print("save url")
              } catch {
                  print("Error saving the url")
              }
  
              DispatchQueue.main.async {
                  self.albumCollection.reloadData()
              }
  
          } else {
              print("Error loading photos")
          }
      }
  }
  

  I can get photos from Flickr.

  I get 9 photo urls, but there is only one photo.

  func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
      print("fr section number is \(fetchedResultsController.sections![section].numberOfObjects)")
      return fetchedResultsController.sections![section].numberOfObjects
  }
  

  The number of section is 1, too.

  And, I can't save these photos. How can I fix these problems?
• UICollectionView with custom cell Autolayout

  Can you guys give me some help with my collectionview? I have problems with the collector cell autolayout ..

  

  As you can see from the image the cells are not aligned, the last cell remains cut, and all subsequent ones are not set properly.

  In my collectionview I use paging for horizontal scrolling, I have tried to follow the estimated autolayout estimates setItemSize as a rule but I can not get the right setting can you help me?

  I show you the code I'm using

  UICollectionView in UIViewController

  @interface controller () <UICollectionViewDelegate, UICollectionViewDataSource>
  @property (weak, nonatomic) IBOutlet UICollectionView *collectionview;
  @end
  
  @implementation controller
  
          - (void)viewDidLoad {
          [super viewDidLoad];
          _collectionview .delegate = self;
          _collectionview.dataSource = self;
          UINib *nib = [UINib nibWithNibName:@"CollectionViewCell" bundle: nil];
          [_collectionview registerNib:nib forCellWithReuseIdentifier:@"cell"];
  
          UICollectionViewFlowLayout *smartLayout = [[UICollectionViewFlowLayout alloc] init];
          smartLayout.scrollDirection = UICollectionViewScrollDirectionHorizontal;
          smartLayout.estimatedItemSize = CGSizeMake(50, 50);
          _collectionview.collectionViewLayout = smartLayout;
          _collectionview.showsHorizontalScrollIndicator = NO;
          [_collectionview
           reloadData];
      }
  
      -(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
          return 30;
      }
  
      -(UICollectionViewCell*)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(nonnull NSIndexPath *)indexPath {
          CollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"cell" forIndexPath:indexPath];
          cell.label.text = @"cia";
          cell.backgroundColor = [UIColor redColor];
          return cell;
      }
  

  UICollectionViewCell custom class

  @implementation CollectionViewCell
  
  - (void)awakeFromNib {
      [super awakeFromNib];
      // Initialization code
  }
  -(UICollectionViewLayoutAttributes *)preferredLayoutAttributesFittingAttributes:(UICollectionViewLayoutAttributes *)layoutAttributes {
      return [super preferredLayoutAttributesFittingAttributes:layoutAttributes];
  }
  
• how to get the cell at index path.item - 1 in collection view

  I want to access the previous cell (index path.item - 1) in my collection view to change some settings there if some conditions are fulfilled in the cell at index path.item

  By now I tried this:

          let previousCell = collectionView.cellForItem(at: indexPath - 1)
  

  But it doesn't work because of the - 1 it is downcast from index path to an integer value.

  How do I get this cell?