Image von Firebase abrufen? (swift)

Question

So habe ich eine Firebase-Struktur wie das Bild unten

Jetzt möchte ich die Bilddatei abrufen, die ich hochgeladen habe. um den base64String zu dekodieren und zu zeigen. Jeder Benutzer kann einen Beitrag verfassen und die Informationen, die an Firebase gesendet werden, haben eine Beschreibung usw. und haben auch ein Bild. Jetzt habe ich versucht, es mit diesen Codes abrufen, aber nichts hat funktioniert.

var REF_LIST = Firebase(url: "\(URL_BASE)/listItems") 

REF_LIST.observeEventType(FEventType.Value, withBlock: { snapshot in 
let image = snapshot.value.objectForKey("images") as! String 

aber das gab mir schon einen Null Fehler in dieser Zeile, so dass ich nicht einmal decodieren konnte. Ich denke, ich verstehe, warum es mir einen Null-Fehler gibt, gibt es keine Bilder in listItems auf firebase, Sie haben zuerst die eindeutige ID und dann die Spezifikationen mit Bildern in. Jetzt weiß ich nicht jetzt, wie ich diese Informationen von diesem einzigartigen abrufen kann ICH WÜRDE?

UPDATE: die Tableviewcontroller, was die Daten von Feuerbasis erhalten:

import UIKit 
import FBSDKLoginKit 
import Alamofire 
import Firebase 

class ListVC: UIViewController, UITableViewDataSource, UITableViewDelegate { 

    @IBOutlet weak var tableView: UITableView! 

    var lists = [List]() 

    override func viewDidLoad() { 
     super.viewDidLoad() 

     tableView.delegate = self 
     tableView.dataSource = self 

     dispatch_async(backgroundQueue, { 
     self.initObservers() 
     }) 

    } 

    override func viewDidAppear(animated: Bool) { 
     super.viewDidAppear(animated) 

     self.tableView.reloadData() 

    } 

    func initObservers() { 

     LoadingOverlay.shared.showOverlay(self.view) 

      DataService.ds.REF_LISTS.observeEventType(.Value, withBlock: { snapshot in 
       print(snapshot.value) 

       self.lists = [] 

       if let snapshots = snapshot.children.allObjects as? [FDataSnapshot] { 


        for snap in snapshots { 
         print("SNAP: \(snap)") 

         if let listDict = snap.value as? Dictionary<String, AnyObject> { 
          let key = snap.key 
          let list = List(listKey: key, dictionary: listDict) 
          self.lists.insert(list, atIndex:0) 
         } 
        } 
       } 

       self.tableView.reloadData() 
       LoadingOverlay.shared.hideOverlayView() 

      }) 
    } 

    func numberOfSectionsInTableView(tableView: UITableView) -> Int { 
     return 1 
    } 

    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int { 
     return lists.count 
    } 

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell { 

     if let cell = tableView.dequeueReusableCellWithIdentifier("ListCell") as? ListCell { 
      let list = self.lists[indexPath.row] 

      cell.request?.cancel() 

      cell.configureCell(list) 

      return cell 

     } else { 

      return ListCell() 
     } 

    } 

} 

die addController, die die Daten auf Feuerbasis schreiben:

import UIKit 
import Firebase 
import Alamofire 
import FBSDKCoreKit 

class AddVC: UIViewController, UITextFieldDelegate, UITextViewDelegate, UIImagePickerControllerDelegate, UINavigationControllerDelegate { 

    @IBOutlet weak var addTitle: UITextField! 
    @IBOutlet weak var addDescription: UITextView! 
    @IBOutlet weak var addLocation: UITextField! 
    @IBOutlet weak var placeholderLbl: UILabel! 
    @IBOutlet weak var freeSwitch: UISwitch! 
    @IBOutlet weak var tradeSwitch: UISwitch! 
    @IBOutlet weak var imageSelectorImg: UIImageView! 
    @IBOutlet weak var overlayView: UIView! 

    var currentUsername = "" 
    var imageSelected = false 
    var imagePicker: UIImagePickerController! 
    var base64String: NSString = "" 

    override func viewDidLoad() { 
     super.viewDidLoad() 

     addTitle.delegate = self 
     addDescription.delegate = self 
     addLocation.delegate = self 

     imagePicker = UIImagePickerController() 
     imagePicker.delegate = self 


     getCurrentUser() 
     hideKeyboardWhenTappedAround() 
    } 

    override func viewWillAppear(animated: Bool) { 
     super.viewWillAppear(animated) 

     addTitle.text = "" 
     addDescription.text = "" 
     addLocation.text = "" 
     freeSwitch.setOn(false, animated: false) 
     tradeSwitch.setOn(false, animated: false) 
     placeholderLbl.hidden = false 
    } 

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

    func getCurrentUser() { 
     DataService.ds.REF_USER_CURRENT.observeEventType(FEventType.Value, withBlock: { snapshot in 

      let currentUser = snapshot.value.objectForKey("username") as! String 

      print("Username: \(currentUser)") 
      self.currentUsername = currentUser }, withCancelBlock: { error in 
       print(error.description) 
     }) 
    } 

    func imagePickerController(picker: UIImagePickerController, didFinishPickingImage image: UIImage, editingInfo: [String : AnyObject]?) { 
     imagePicker.dismissViewControllerAnimated(true, completion: nil) 
     imageSelectorImg.image = image 
     dispatch_async(backgroundQueue, { 
     let uploadImage = image 
     let imageData = UIImageJPEGRepresentation(uploadImage, 0.5) 
     self.base64String = imageData!.base64EncodedStringWithOptions(NSDataBase64EncodingOptions.Encoding64CharacterLineLength) 
     }) 

     imageSelected = true 
    } 

    @IBAction func selectImage(sender: UITapGestureRecognizer) { 
     presentViewController(imagePicker, animated: true, completion: nil) 
    } 


    func postToFirebase() { 

     // LoadingOverlay.shared.showOverlay(self.overlayView) 
     var post: Dictionary<String, AnyObject> = ["username": self.currentUsername, "description": self.addDescription.text!, "title": self.addTitle.text!, "location": self.addLocation.text!, "images": self.base64String] 

     if self.freeSwitch.on && self.tradeSwitch.on { 
      post["tradeOption"] = "Gratis/Te ruil" 
     } else if self.freeSwitch.on { 
      post["tradeOption"] = "Gratis" 
     } else if self.tradeSwitch.on { 
      post["tradeOption"] = "Te ruil" 
     } 

     let firebasePost = DataService.ds.REF_LISTS.childByAutoId() 
     firebasePost.setValue(post) 

    } 


    @IBAction func postListItem(sender: AnyObject) { 

     if let addTitle = addTitle.text where addTitle != "", let addDescription = addDescription.text where addDescription != "", let addLocation = addLocation.text where addLocation != "" { 

      dispatch_async(backgroundQueue, { 
       self.postToFirebase() 

       dispatch_async(dispatch_get_main_queue(), {() -> Void in 

        let storyboard = UIStoryboard(name: "Main", bundle: nil) 
        let listVC = storyboard.instantiateViewControllerWithIdentifier("TBC") as! UITabBarController 
        listVC.selectedIndex = 1 
        self.presentViewController(listVC, animated: false, completion: nil) 
       }) 
      }) 
     } 
    } 

    func textViewDidBeginEditing(textView: UITextView) { 
     placeholderLbl.hidden = true 
    } 

    func textViewDidEndEditing(textView: UITextView) { 
     if textView.text == "" { 
      placeholderLbl.hidden = false 
     } 
    } 

    func textFieldShouldReturn(textField: UITextField) -> Bool { 
     textField.resignFirstResponder() 

     return true 
    } 

} 

und die schnelle Datei, um die Zelle zu konfigurieren :

import UIKit 
import Alamofire 
import Firebase 

class ListCell: UITableViewCell { 

    @IBOutlet weak var listImg: UIImageView! 
    @IBOutlet weak var listTitle: UILabel! 
    @IBOutlet weak var listTradeOption: UILabel! 
    @IBOutlet weak var listLocation: UILabel! 
    @IBOutlet weak var headImg: UIImageView! 

    var list: List! 

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

    func retrieveImages() { 
    DataService.ds.REF_LISTS.observeEventType(FEventType.Value, withBlock: { snapshot in 

     if let snapshots = snapshot.children.allObjects as? [FDataSnapshot] { 

      for snap in snapshots { 
       let image = snap.value.objectForKey("images") as! String 

       let decodedData = NSData(base64EncodedString: image, options: NSDataBase64DecodingOptions.IgnoreUnknownCharacters) 
       let decodedImage = UIImage(data: decodedData!) 
       self.headImg.image = decodedImage 

      } 
     } 

    }) 
} 

func configureCell(list: List) { 

    self.list = list 
    self.listTitle.text = list.listTitle 
    self.listTradeOption.text = list.listTradeOption 
    self.listLocation.text = list.listLocation 
    retrieveImages() 

} 

}

auch die Liste Modell-Datei:

import Foundation 
import Firebase 

class List { 
    private var _listTitle: String! 
    private var _listDescription: String! 
    private var _listTradeOption: String! 
    private var _listLocation: String! 
    private var _listImageURL: String? 
    private var _listKey: String! 
    private var _listRef: Firebase! 

    var listTitle: String? { 
     return _listTitle 
    } 

    var listDescription: String? { 
     return _listDescription 
    } 

    var listTradeOption: String? { 
     return _listTradeOption 
    } 

    var listLocation: String? { 
     return _listLocation 
    } 

    var listKey: String { 
     return _listKey 
    } 

    var listImageURL: String? { 
     return _listImageURL 
    } 

    init(title: String, description: String, tradeOption: String, location: String, listImageURL: String?) { 
     self._listTitle = title 
     self._listDescription = description 
     self._listTradeOption = tradeOption 
     self._listLocation = location 
     self._listImageURL = listImageURL 
    } 

    init(listKey: String, dictionary: Dictionary<String, AnyObject>) { 
     self._listKey = listKey 

     if let title = dictionary ["title"] as? String { 
      self._listTitle = title 
     } 

     if let desc = dictionary ["description"] as? String { 
      self._listDescription = desc 
     } 

     if let trade = dictionary ["tradeOption"] as? String { 
      self._listTradeOption = trade 
     } 

     if let loc = dictionary ["location"] as? String { 
      self._listLocation = loc 
     } 

     if let imgUrl = dictionary["images"] as? String { 
      self._listImageURL = imgUrl 
     } 

     self._listRef = DataService.ds.REF_LISTS.childByAppendingPath(self._listKey) 
    } 

} 

ich habe auch eine DataServicefile, wo ich einen Benutzer durch eindeutige ID mit diesem Code erstellen:

var REF_USER_CURRENT: Firebase { 
     let uid = NSUserDefaults.standardUserDefaults().valueForKey(KEY_UID) as! String 
     let user = Firebase(url: "\(REF_BASE)").childByAppendingPath("users").childByAppendingPath(uid) 
     return user! 
    } 

    func createFirebaseUser(uid: String, user: Dictionary<String, String>) { 
     REF_USERS.childByAppendingPath(uid).setValue(user) 
    } 

ich weiß, es ist viel, aber vielleicht der beste Weg, um zu helfen :)

Answer 1

Versuchen Sie, dies in der List Cell

zu bearbeiten