11強目標

Drag and Drop

Demo

class EmojiArtViewController: UIViewController, UIDropInteractionDelegate {

    @IBOutlet weak var dropZone: UIView! {
        didSet {
            dropZone.addInteraction(UIDropInteraction(delegate: self))
        }
    }
    
    // 관심있는 것은 이미지와 이미지에 대한 URL
    func dropInteraction(_ interaction: UIDropInteraction, canHandle session: UIDropSession) -> Bool {
        return session.canLoadObjects(ofClass: NSURL.self) && session.canLoadObjects(ofClass: UIImage.self)
    }
    
    // 복사해서 가져온다.
    func dropInteraction(_ interaction: UIDropInteraction, sessionDidUpdate session: UIDropSession) -> UIDropProposal {
        return UIDropProposal(operation: .copy)
    }
    
    var imageFetcher: ImageFetcher! // 강의 Utilities.swift 파일
    
    func dropInteraction(_ interaction: UIDropInteraction, performDrop session: UIDropSession) {
        imageFetcher = ImageFetcher() { (url, image) in
            DispatchQueue.main.async {
                self.emojiArtView.backgroundImage = image
            }
        }
        
        session.loadObjects(ofClass: NSURL.self) { nsurls in
            if let url = nsurls.first as? URL {
                self.imageFetcher.fetch(url)
            }
        }
        session.loadObjects(ofClass: UIImage.self) { images in
            if let image = images.first as? UIImage {
                self.imageFetcher.backup = image
            }
        }
    }
}

Table View, Collection View

Demo

class EmojiArtDocumentTableViewController: UITableViewController {
    
    var emojiArtDocuments = ["One", "Two", "Three"]
    
    // MARK: - UITableViewDataSource

    // section의 개수
    override func numberOfSections(in tableView: UITableView) -> Int {
        return 1
    }

    // section마다 행의 개수
    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return emojiArtDocuments.count
    }

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        // 재사용할 수 있는 큐
        let cell = tableView.dequeueReusableCell(withIdentifier: "DocumentCell", for: indexPath)

        cell.textLabel?.text = emojiArtDocuments[indexPath.row]

        return cell
    }

    // + 버튼 클릭 시 배열에 Untitled를 추가하지만 Utilities.swift에 있는 메소드를 활용해 이름 중복이 발생해도 숫자가 뒤에 붙는다.
    @IBAction func newEmojiArt(_ sender: UIBarButtonItem) {
        emojiArtDocuments += ["Unititled".madeUnique(withRespectTo: emojiArtDocuments)]
        tableView.reloadData() // 테이블뷰 새로고침
    }
    
    /*
    // 행 편집 가능 (기본값: true)
    // Override to support conditional editing of the table view.
    override func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
        // Return false if you do not want the specified item to be editable.
        return true
    }
    */
    
    // 행 삭제일 경우에 배열에서 삭제하고 테이블뷰에서도 삭제
    override func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {
        if editingStyle == .delete {
            emojiArtDocuments.remove(at: indexPath.row)
            tableView.deleteRows(at: [indexPath], with: .fade)
        } else if editingStyle == .insert {
            
        }    
    }
}

12強目標

CollectionView

Demo

UITextField

リンク