2017-12-27 131 views
0

我想保存在此应用程序的表情符号,我在苹果的书中学到什么,但问题是,我不明白书中的下一步的文件管理器,保存在swift4

创建一个静态loadSampleEmojis()方法,该方法将创建并返回预定义的[表情符号]集合。您可以使用EmojiTableViewController中分配给表情符号的列表作为项目列表。

更新表情符号将被初始化为空的集合,而不是一个大样本collection.When的viewDidLoad中()方法被调用,你应该检查文件/目录表情符号使用loadFromfile(任何先前保存的绘文字对象)。如果他们被发现将它们分配给emojis.if不会将emojis分配给loadSampleEmojis()的结果。

花点时间思考何时可能适合保存您的Emoji对象。 在这种情况下,您的日期的中心点是emojis携带Emojitableviewcontroller,意味着只要emojis属性发生更改,就可以调用saveToFile(emojis:)。 接下来,请考虑何时载入您的归档Emoji objects.again,在这种简单的情况下,真正只有一点需要将归档数据取消归档:何时第一个视图载入。您应该已经调用了这个方法在第一个视图控制器viewdidload()中。

这是我写的,直到如今,

import Foundation 


struct Emoji : Codable { 
    var symbol : String 
    var name : String 
    var description : String 
    var usage : String 
    static let documentsdirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first! 
    static let archiveurl = documentsdirectory.appendingPathComponent("emojis").appendingPathExtension("plist") 

    static func SaveToFile (emojis: [Emoji]) { 
     let propetyencod = PropertyListEncoder() 
     let encodemoj = try? propetyencod.encode(emojis) 
     try? encodemoj?.write(to : archiveurl , options : .noFileProtection) 
    } 
    static func loadeFromFile() -> [Emoji] { 
    let propetydicod = PropertyListDecoder() 
     if let retrivdate = try? Data(contentsOf: archiveurl), 
     let decodemoj = try? 
      propetydicod.decode(Array<Emoji>.self, from: retrivdate){ 
    return decodemoj 

     } 
     return [Emoji]() 
    } 



} 



import UIKit 

class emojiTableViewController: UITableViewController { 

    var emojis : [Emoji] = [ 
     Emoji(symbol: "", name: "Grinning Face", 
       description: "A typical smiley face.", usage: "happiness"), 
     Emoji(symbol: "", name: "Confused Face", 
       description: "A confused, puzzled face.", usage: "unsure what to think; displeasure"), 
     Emoji(symbol: "", name: "Heart Eyes", 
       description: "A smiley face with hearts for eyes.", 
       usage: "love of something; attractive"), 
     Emoji(symbol: "", name: "Police Officer", 
       description: "A police officer wearing a blue cap with a gold badge.", usage: "person of authority"), 
     Emoji(symbol: "", name: "Turtle", description: 
      "A cute turtle.", usage: "Something slow"), 
     Emoji(symbol: "", name: "Elephant", description: 
      "A gray elephant.", usage: "good memory"), 
     Emoji(symbol: "", name: "Spaghetti", 
       description: "A plate of spaghetti.", usage: "spaghetti"), 
     Emoji(symbol: "", name: "Die", description: "A single die.", usage: "taking a risk, chance; game"), 
     Emoji(symbol: "⛺️", name: "Tent", description: "A small tent.", usage: "camping"), 
     Emoji(symbol: "", name: "Stack of Books", 
       description: "Three colored books stacked on each other.", 
       usage: "homework, studying"), 
     Emoji(symbol: "", name: "Broken Heart", 
       description: "A red, broken heart.", usage: "extreme sadness"), Emoji(symbol: "", name: "Snore", 
                        description: 
       "Three blue \'z\'s.", usage: "tired, sleepiness"), 
                       Emoji(symbol: "", name: "Checkered Flag", 
                        description: "A black-and-white checkered flag.", usage: 
                       "completion")] 

    override func viewDidLoad() { 
     super.viewDidLoad() 


     navigationItem.leftBarButtonItem = editButtonItem 


     tableView.rowHeight = UITableViewAutomaticDimension 
     tableView.estimatedRowHeight = 52.0 
     // Uncomment the following line to preserve selection between presentations 
     // self.clearsSelectionOnViewWillAppear = false 

     // Uncomment the following line to display an Edit button in the navigation bar for this view controller. 
     // self.navigationItem.rightBarButtonItem = self.editButtonItem() 
    } 

    override func didReceiveMemoryWarning() { 
     super.didReceiveMemoryWarning() 
     // Dispose of any resources that can be recreated. 
    } 

    // MARK: - Table view data source 

    override func numberOfSections(in tableView: UITableView) -> Int { 
     // #warning Incomplete implementation, return the number of sections 
     return 1 
    } 

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int { 
     // #warning Incomplete implementation, return the number of rows 
     if section == 0 { 
      return emojis.count 
     }else{ 
      return 0 
     } 
    } 


    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell { 
     let cell = tableView.dequeueReusableCell(withIdentifier: "emojicell", for: indexPath) as! cellviewTableViewCell 

     let emoji = emojis[indexPath.row] 
     cell.update(with: emoji) 

     cell.showsReorderControl = true 
     return cell 
    } 


    @IBAction func editbutton(_ sender: UIBarButtonItem) { 
     let tablevieweditingmod = tableView.isEditing 

     tableView.setEditing(!tablevieweditingmod, animated: true) 

    } 

    override func tableView(_ tableView: UITableView, editingStyleForRowAt indexPath: IndexPath) -> UITableViewCellEditingStyle { 
     return.delete 

    } 

    override func viewWillAppear(_ animated: Bool) { 
    tableView.reloadData() 
    } 

    /* 
    // 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 
    } 
    */ 


    // Override to support editing the table view. 
    override func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) { 
     if editingStyle == .delete { 
      // Delete the row from the data source 
      emojis.remove(at: indexPath.row) 
      tableView.deleteRows(at: [indexPath], with: .automatic) 
     } else if editingStyle == .insert { 
      // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view 
     }  
    } 



    // Override to support rearranging the table view. 
    override func tableView(_ tableView: UITableView, moveRowAt fromIndexPath: IndexPath, to: IndexPath) { 
     let movedEmoji = emojis.remove(at: fromIndexPath.row) 
     emojis.insert(movedEmoji, at: to.row) 
     tableView.reloadData() 
    } 
    /* 
    // Override to support conditional rearranging of the table view. 
    override func tableView(_ tableView: UITableView, canMoveRowAt indexPath: IndexPath) -> Bool { 
     // Return false if you do not want the item to be re-orderable. 
     return true 
    } 
    */ 

    /* 
    // MARK: - Navigation 

    // In a storyboard-based application, you will often want to do a little preparation before navigation 
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) { 
     // Get the new view controller using segue.destinationViewController. 
     // Pass the selected object to the new view controller. 
    } 
    */ 
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) { 
     if segue.identifier == "editcell"{ 
     let indexpath = tableView.indexPathForSelectedRow! 
     let emoji = emojis[indexpath.row] 
      let edittableview = segue.destination as! addTableViewController 
      edittableview.emoji = emoji 
    } 
} 
    @IBAction func unwindToemojitableview(segue: UIStoryboardSegue){ 

     guard segue.identifier == "saveun" else {return} 
     let sourseviewcontroler = segue.source as! addTableViewController 
     if let emoji = sourseviewcontroler.emoji{ 
      if let selectedindexpath = tableView.indexPathForSelectedRow{ 
       emojis[selectedindexpath.row] = emoji 
       tableView.reloadRows(at: [selectedindexpath], with: .none) 
      }else { 
       let newindexpath = IndexPath(row: emojis.count, section: 0) 
       emojis.append(emoji) 
       tableView.insertRows(at: [newindexpath], with: .automatic) 
      } 
     } 
    } 

} 





import UIKit 

class addTableViewController: UITableViewController { 

    var emoji : Emoji? 

    @IBOutlet weak var symboltexfiel: UITextField! 
    @IBOutlet weak var nametexfiel: UITextField! 
    @IBOutlet weak var descriptexfiel: UITextField! 
    @IBOutlet weak var usagetexfiel: UITextField! 
    @IBOutlet weak var savebutt: UIBarButtonItem! 


    override func viewDidLoad() { 

     super.viewDidLoad() 
     if let emoji = emoji{ 
      symboltexfiel.text = emoji.symbol 
      nametexfiel.text = emoji.name 
      descriptexfiel.text = emoji.description 
      usagetexfiel.text = emoji.usage 
     } 
     ubdatesavebutt() 
    } 
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) { 
     super.prepare(for: segue, sender: sender) 
     guard segue.identifier == "saveun" else {return} 
     let sym = symboltexfiel.text ?? "" 
     let nam = nametexfiel.text ?? "" 
     let de = descriptexfiel.text ?? "" 
     let use = usagetexfiel.text ?? "" 
     emoji = Emoji(symbol: sym, name: nam, description: de, usage: use) 
    } 


    func ubdatesavebutt() { 
     let symbol = symboltexfiel.text ?? "" 
     let name = nametexfiel.text ?? "" 
     let descr = descriptexfiel.text ?? "" 
     let use = usagetexfiel.text ?? "" 
     savebutt.isEnabled = !symbol.isEmpty && !name.isEmpty && !descr.isEmpty && !use.isEmpty 
    } 

    @IBAction func ediittex(_ sender: UITextField) { 
     ubdatesavebutt() 
    } 

} 


    import UIKit 

    class cellviewTableViewCell: UITableViewCell { 

     @IBOutlet weak var symbollabel: UILabel! 
     @IBOutlet weak var namelabel: UILabel! 
     @IBOutlet weak var descriptionlabel: UILabel! 


     override func awakeFromNib() { 
      super.awakeFromNib() 
      // Initialization code 
     } 

     override func setSelected(_ selected: Bool, animated: Bool) { 
      super.setSelected(selected, animated: animated) 

      // Configure the view for the selected state 
     } 

     func update(with emoji : Emoji) { 
      symbollabel.text = emoji.symbol 
      namelabel.text = emoji.name 
      descriptionlabel.text = emoji.description 
     } 


    } 

回答

0

首先,您将需要添加静态方法,将返回[表情],并包含您的表情符号预设(从表情符表视图控制器)。

static func loadSampleEmojis() -> [Emoji]{ 
    return [Your emojis array]} 

之后,在表情符号表视图控制器,你需要定义像

var emojis = [Emoji]() 

接下来,在viedDidLoad(表情符号),您需要检查是否有任何数据你的ArchiveURL?如果是 - 将其分配到您的表情符号,否则分配预设。

if let savedEmojis = Emoji.loadFromFile() { 
emojis = savedEmojis 
} else { 
emojis = Emoji.loadSampleEmoji()} 

而在这之后添加

Emoji.saveToFile(emoji: emojis) 

到的tableView(_,moveRowAt:,到:),的tableView(editingStyle)和unwindSegue。

此外,您还需要更正:在viewDidLoad中

static func loadFromFile() -> [Emoji]? {..} 

或控制流将无法正常工作。

+0

非常感谢你,先生....你是男人 – user8058965