这是我的情况:
我有一个“Feed” Controller ,它通过 Firebase 中的表格(标题和图像)列出多个帖子。
按一下按钮,它就会进入“提要详细信息” Controller ,我希望在其中显示先前单击的帖子(父级)中的数据(标题图像和标题)。 (见截图2)
目前,当我到达提要详细信息 Controller 时,没有任何内容被获取......
如何从之前点击的项目中获取详细信息?
目前这是我的提要 Controller :
//
// FeedVC.swift
// MobileAppDemo
//
// Created by Mikko Hilpinen on 31.10.2016.
// Copyright © 2016 Mikkomario. All rights reserved.
//
import UIKit
import FirebaseAuth
import FirebaseDatabase
import FirebaseStorage
import SwiftKeychainWrapper
import SwiftyJSON
class FeedVC: UIViewController, UITableViewDataSource, UIImagePickerControllerDelegate, UINavigationControllerDelegate
{
@IBOutlet weak var addImageView: UIImageView!
@IBOutlet weak var feedTableView: UITableView!
@IBOutlet weak var titleInputView: InputTextView!
@IBOutlet weak var captionInputView: InputTextView!
private var posts = [Post]()
private var imagePicker = UIImagePickerController()
private var imageSelected = false
private var readPosts: ObserveTask?
override func viewDidLoad()
{
super.viewDidLoad()
imagePicker.delegate = self
imagePicker.allowsEditing = true
feedTableView.dataSource = self
feedTableView.rowHeight = UITableViewAutomaticDimension
feedTableView.estimatedRowHeight = 320
readPosts = Post.observeList(from: Post.parentReference.queryOrdered(byChild: Post.PROPERTY_CREATED))
{
posts in
self.posts = posts.reversed()
self.feedTableView.reloadData()
}
}
func numberOfSections(in tableView: UITableView) -> Int
{
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
return posts.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
if let cell = tableView.dequeueReusableCell(withIdentifier: "MessageCell", for: indexPath) as? MessageCell
{
let post = posts[indexPath.row]
cell.configureCell(tableView: tableView, post: post)
return cell
}
else
{
fatalError()
}
}
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any])
{
if let image = info[UIImagePickerControllerEditedImage] as? UIImage
{
addImageView.image = image
imageSelected = true
}
picker.dismiss(animated: true, completion: nil)
}
@IBAction func selectImagePressed(_ sender: AnyObject)
{
present(imagePicker, animated: true, completion: nil)
}
@IBAction func postButtonPressed(_ sender: AnyObject)
{
guard let caption = captionInputView.text, !caption.isEmpty else
{
// TODO: Inform the user
print("POST: Caption must be entered")
return
}
guard let title = titleInputView.text, !title.isEmpty else
{
// TODO: Inform the user
print("POST: title must be entered")
return
}
guard let image = addImageView.image, imageSelected else
{
print("POST: Image must be selected")
return
}
guard let currentUserId = User.currentUserId else
{
print("POST: Can't post before logging in")
return
}
imageSelected = false
addImageView.image = UIImage(named: "add-image")
captionInputView.text = nil
titleInputView.text = nil
// Uploads the image
if let imageData = UIImageJPEGRepresentation(image, 0.2)
{
let imageUid = NSUUID().uuidString
let metadata = FIRStorageMetadata()
metadata.contentType = "image/jpeg"
Storage.REF_POST_IMAGES.child(imageUid).put(imageData, metadata: metadata)
{
(metadata, error) in
if let error = error
{
print("STORAGE: Failed to upload image to storage \(error)")
}
if let downloadURL = metadata?.downloadURL()?.absoluteString
{
// Caches the image for faster display
Storage.imageCache.setObject(image, forKey: downloadURL as NSString)
print("STORAGE: Successfully uploaded image to storage")
_ = Post.post(caption: caption, title: title, imageUrl: downloadURL, creatorId: currentUserId)
}
}
}
}
@IBAction func signOutButtonPressed(_ sender: AnyObject)
{
// Doesn't listen to posts anymore
readPosts?.stop()
try! FIRAuth.auth()?.signOut()
User.currentUserId = nil
dismiss(animated: true, completion: nil)
}
}
我正在使用 feeddetails 的代码 - 这当然不支持数据
我的数据库结构如下所示:
如何获取详细信息 View 中的数据?如果有人能向我解释这个过程,那就太棒了!
感谢您的所有时间和帮助!!
-----编辑:--------
感谢 Retterdesdialogs,我已经更新了代码并启动了应用程序,但是当我单击按钮 linkbutton 时什么也没有发生并且应用程序崩溃了:
控制台显示: 无法将“UIViewController”类型的值 (0x1087f6758) 转换为“MobileAppDemo.FeedDetailsController”(0x104bc34a0)。
我现在有代码:
feedVC.swift(列出了所有帖子):
//
// FeedVC.swift
// MobileAppDemo
//
// Created by Mikko Hilpinen on 31.10.2016.
// Copyright © 2016 Mikkomario. All rights reserved.
//
import UIKit
import FirebaseAuth
import FirebaseDatabase
import FirebaseStorage
import SwiftKeychainWrapper
import SwiftyJSON
class FeedVC: UIViewController, UITableViewDataSource, UIImagePickerControllerDelegate, UINavigationControllerDelegate
{
@IBOutlet weak var addImageView: UIImageView!
@IBOutlet weak var feedTableView: UITableView!
@IBOutlet weak var titleInputView: InputTextView!
@IBOutlet weak var linkbutton: UIButton!
@IBOutlet weak var captionInputView: InputTextView!
private var posts = [Post]()
private var imagePicker = UIImagePickerController()
private var imageSelected = false
private var readPosts: ObserveTask?
override func viewDidLoad()
{
super.viewDidLoad()
imagePicker.delegate = self
imagePicker.allowsEditing = true
feedTableView.dataSource = self
feedTableView.rowHeight = UITableViewAutomaticDimension
feedTableView.estimatedRowHeight = 320
readPosts = Post.observeList(from: Post.parentReference.queryOrdered(byChild: Post.PROPERTY_CREATED))
{
posts in
self.posts = posts.reversed()
self.feedTableView.reloadData()
}
}
func numberOfSections(in tableView: UITableView) -> Int
{
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
return posts.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
// here you need to add
{
if let cell = tableView.dequeueReusableCell(withIdentifier: "MessageCell", for: indexPath) as? MessageCell
{
let post = posts[indexPath.row]
cell.configureCell(tableView: tableView, post: post)
cell.linkbutton.tag = indexPath.row
cell.linkbutton.addTarget(self, action: #selector(FeedVC.toFeedDetailAction(_:)), for: .touchUpInside)
return cell
}
else
{
fatalError()
}
}
func toFeedDetailAction(_ sender: UIButton) {
let FeedDetailsController = self.storyboard?.instantiateViewController(withIdentifier: "FeedDetailsIdentifier") as! FeedDetailsController
FeedDetailsController.post = posts[sender.tag]
self.navigationController?.pushViewController(FeedDetailsController, animated: true)
}
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any])
{
if let image = info[UIImagePickerControllerEditedImage] as? UIImage
{
addImageView.image = image
imageSelected = true
}
picker.dismiss(animated: true, completion: nil)
}
@IBAction func selectImagePressed(_ sender: AnyObject)
{
present(imagePicker, animated: true, completion: nil)
}
@IBAction func postButtonPressed(_ sender: AnyObject)
{
guard let caption = captionInputView.text, !caption.isEmpty else
{
// TODO: Inform the user
print("POST: Caption must be entered")
return
}
guard let title = titleInputView.text, !title.isEmpty else
{
// TODO: Inform the user
print("POST: title must be entered")
return
}
guard let image = addImageView.image, imageSelected else
{
print("POST: Image must be selected")
return
}
guard let currentUserId = User.currentUserId else
{
print("POST: Can't post before logging in")
return
}
imageSelected = false
addImageView.image = UIImage(named: "add-image")
captionInputView.text = nil
titleInputView.text = nil
// Uploads the image
if let imageData = UIImageJPEGRepresentation(image, 0.2)
{
let imageUid = NSUUID().uuidString
let metadata = FIRStorageMetadata()
metadata.contentType = "image/jpeg"
Storage.REF_POST_IMAGES.child(imageUid).put(imageData, metadata: metadata)
{
(metadata, error) in
if let error = error
{
print("STORAGE: Failed to upload image to storage \(error)")
}
if let downloadURL = metadata?.downloadURL()?.absoluteString
{
// Caches the image for faster display
Storage.imageCache.setObject(image, forKey: downloadURL as NSString)
print("STORAGE: Successfully uploaded image to storage")
_ = Post.post(caption: caption, title: title, imageUrl: downloadURL, creatorId: currentUserId)
}
}
}
}
@IBAction func signOutButtonPressed(_ sender: AnyObject)
{
// Doesn't listen to posts anymore
readPosts?.stop()
try! FIRAuth.auth()?.signOut()
User.currentUserId = nil
dismiss(animated: true, completion: nil)
}
}
和 FeedDetails.swift (单击按钮后会列出详细信息,按钮具有来自 viewVC Controller 的类:linkbutton:
//
// FeedDetailsController.swift
// MobileAppDemo
//
// Created by Mikko Hilpinen on 27.10.2016.
// Copyright © 2016 Mikkomario. All rights reserved.
//
import UIKit
import FBSDKCoreKit
import FBSDKLoginKit
import Firebase
import FirebaseAuth
import SwiftKeychainWrapper
fileprivate struct RegisterInfo
{
let email: String
let password: String
}
class FeedDetailsController: UIViewController
{
@IBOutlet weak var emailField: UITextField!
@IBOutlet weak var passwordField: UITextField!
var post: Post!
override func viewDidLoad()
{
super.viewDidLoad()
}
override func viewDidAppear(_ animated: Bool)
{
if User.currentUserId != nil
{
print("AUTH: USING EXISTING KEYCHAIN")
User.startTrackingCurrentUser()
performSegue(withIdentifier: "ToFeed", sender: nil)
}
else
{
print("AUTH: NO EXSTING KEYCHAIN")
}
}
override func didReceiveMemoryWarning()
{
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?)
{
print("AUTH: Preparing for segue \(segue.identifier)")
if let registrationVC = segue.destination as? RegisterVC
{
print("AUTH: Found registration VC")
if let info = sender as? RegisterInfo
{
print("AUTH: Sending email (\(info.email)) and password (\(info.password.characters.count) chars) information: ")
registrationVC.setBaseInfo(email: info.email, password: info.password)
}
}
}
@IBAction func signInButtonPressed(_ sender: UIButton)
{
if let email = emailField.text, let password = passwordField.text
{
FIRAuth.auth()?.signIn(withEmail: email, password: password)
{
(user, error) in
if let error = error
{
// TODO: Handle other errors here as well
switch FIRAuthErrorCode(rawValue: error._code)!
{
case .errorCodeUserNotFound:
print("AUTH: USER NOT FOUND -> CREATING NEW USER")
print("AUTH: Sending email \(email) and password \(password.characters.count) characters")
self.performSegue(withIdentifier: "RegisterUser", sender: RegisterInfo(email: email, password: password))
default: print("AUTH: ERROR IN EMAIL LOGIN \(error)") // TODO: Inform user
}
}
else
{
print("AUTH: EMAIL AUTH SUCCESSFUL")
User.currentUserId = user?.uid
User.startTrackingCurrentUser()
self.performSegue(withIdentifier: "ToFeed", sender: nil)
}
}
}
// TODO: Inform user that the field contents are missing
}
@IBAction func facebookButtonPressed(_ sender: UIButton)
{
// (Already logged in to FB)
if let fbAccessToken = FBSDKAccessToken.current()
{
print("AUTH: Already logged in to FB")
firebaseAuth(with: FIRFacebookAuthProvider.credential(withAccessToken: fbAccessToken.tokenString))
}
else
{
let facebookLogin = FBSDKLoginManager()
facebookLogin.logIn(withReadPermissions: ["public_profile", "email"], from: self)
{
(result, error) in
if let error = error
{
print("AUTH: UNABLE TO AUTHENTICATE WITH FACEBOOK")
print("AUTH: \(error)")
}
else if let result = result
{
if result.isCancelled
{
print("AUTH: USER CANCELLED FACEBOOK AUTH")
}
else
{
print("AUTH: FACEBOOK AUTH SUCCESS")
let credential = FIRFacebookAuthProvider.credential(withAccessToken: FBSDKAccessToken.current().tokenString)
self.firebaseAuth(with: credential)
}
}
}
}
}
fileprivate func firebaseAuth(with credential: FIRAuthCredential)
{
if FIRAuth.auth() == nil
{
print("AUTH: NO AUTH SERVICE AVAILABLE")
}
FIRAuth.auth()?.signIn(with: credential)
{
(user, error) in
if let error = error
{
print("AUTH: UNABLE TO AUTHENTICATE TO FIREBASE")
print("AUTH: \(error)")
}
else
{
if let user = user
{
print("AUTH: SUCCESSFULLY AUTHENTICATED WITH FIREBASE")
// Updates current user data
var userName = "User"
var image: UIImage?
if let retrievedName = user.displayName
{
userName = retrievedName
}
if let retrievedImageUrl = user.photoURL
{
if let data = try? Data(contentsOf: retrievedImageUrl)
{
image = UIImage(data: data)
}
}
User.post(uid: user.uid, provider: user.providerID, userName: userName, image: image)
{
user in
User.currentUser = user
User.startTrackingCurrentUser()
self.performSegue(withIdentifier: "ToFeed", sender: nil)
}
}
}
}
}
}
最佳答案
1) 您需要能够通过 IBOutlet 或以编程方式访问该按钮
2)将按钮设置为单元格indexPath.row并向其添加操作
let post = posts[indexPath.row]
cell.configureCell(tableView: tableView, post: post)
// here you need to add
cell.yourButton.tag = indexPath.row
cell.yourButton.addTarget(self, action: #selector(FeedViewController.toFeedDetailAction(_:)), for: .touchUpInside)
return cell
3) 当您按下按钮时,您可以识别您的提要,因为您有按钮标签,因此您可以从帖子数组中知道提要
func toFeedDetailAction(_ sender: UIButton) {
let feedDetailsViewController = self.storyboard?.instantiateViewController(withIdentifier: "FeedDetailsIdentifier") as! FeedDetailsViewController
feedDetailsViewController.post = posts[sender.tag]
self.navigationController?.pushViewController(feedDetailsViewController, animated: true)
}
4) 在您的 FeedDetailsViewController 添加
var post: Post!
5) 在 FeedDetailsViewController 中对帖子执行您想要的操作
希望这有帮助:)
关于ios Firebase - 在 "details post" Controller 中继续数据,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/42025159/