将结果从 Swift 数组传递到 Segue 到描述
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【中文标题】将结果从 Swift 数组传递到 Segue 到描述【英文标题】:Passing result from Swift Array to Segue to Description 【发布时间】:2017-11-20 12:11:24 【问题描述】:对 Swift 有点陌生,但目前为止很享受挑战。我已经编写了一些代码,但想知道如何从 Swift 中的 firebase 数组中传递选择以将控制器移动到描述中?我一直以 Chris 为基础编写代码,但其中未涵盖数组。
这是我的搜索数组和 segue 代码。阵列工作正常,但选择单元格时,会出现Segue但没有详细地提出即可。文本标签为空。
提前致谢。
这是将 Firebase 信息解析为数组的代码
import UIKit
import Firebase
class LocateTableViewController: UITableViewController, UISearchResultsUpdating
@IBOutlet var locateTableView: UITableView!
let searchController = UISearchController(searchResultsController: nil)
var firManager:FirebaseManager?
var placesArray = [NSDictionary?]()
var filtersPlaces = [NSDictionary?]()
override func viewDidLoad()
super.viewDidLoad()
searchController.searchResultsUpdater = self
self.searchController.searchBar.placeholder = "Search bars, brewpubs, shops..."
searchController.dimsBackgroundDuringPresentation = false
definesPresentationContext = true
tableView.tableHeaderView = searchController.searchBar
tableView.tableHeaderView = searchController.searchBar
let databaseRef = Database.database().reference()
// search based on name of place
databaseRef.child("places").queryOrdered(byChild: "name").observe(.childAdded, with: (snapshot) in
self.placesArray.append(snapshot.value as? NSDictionary)
// insert rows
self.locateTableView.insertRows(at: [IndexPath(row:self.placesArray.count-1,section:0)], with: UITableViewRowAnimation.automatic)
) (error) in
print(error.localizedDescription)
// 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 searchController.isActive && searchController.searchBar.text != ""
return filtersPlaces.count
return self.placesArray.count
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
// Configure the cell...
let place : NSDictionary?
if searchController.isActive && searchController.searchBar.text != ""
place = filtersPlaces[indexPath.row]
else
place = self.placesArray[indexPath.row]
cell.textLabel?.text = place?["type"] as? String
cell.detailTextLabel?.text = place?["name"] as? String
return cell
// MARK: - Navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?)
// Check if there's a selection first
if let actualIndexPath = tableView.indexPathForSelectedRow
if segue.identifier == "detailSegue"
// Get the selected place
let selectedPlace = getPlaceForIndex(indexPath: actualIndexPath)
// Create the detail model and set the place
let detailModel = DetailModel()
detailModel.place = selectedPlace
// Set the detail model for the Detail View Controller
let detailVC = segue.destination as! DetailViewController
detailVC.model = detailModel
func updateSearchResults(for searchController: UISearchController)
filterContent(searchText: self.searchController.searchBar.text!)
// Update search results
func filterContent(searchText: String)
self.filtersPlaces = self.placesArray.filter place in
let placename = place!["name"] as? String
return(placename?.lowercased().contains(searchText.lowercased()))!
tableView.reloadData()
func getPlaceForIndex(indexPath:IndexPath) -> Place
return places[indexPath.row]
这是信息应该进入的详细视图控制器的代码:
import UIKit
class DetailViewController: UIViewController, DetailModelDelegate, WriteReviewChildViewControllerDelegate
// MARK: - Properties
var place:Place?
var model:DetailModel?
var currentViewController:UIViewController?
@IBOutlet weak var placeImageView: UIImageView!
@IBOutlet weak var nameLabel: UILabel!
@IBOutlet weak var categoryLabel: UILabel!
@IBOutlet weak var faveButton: UIButton!
@IBOutlet weak var descriptionSectionButton: UIButton!
@IBOutlet weak var reviewsSectionButton: UIButton!
@IBOutlet weak var writeReviewSectionButton: UIButton!
@IBOutlet weak var containerView: UIView!
@IBOutlet weak var viewTopConstraint: NSLayoutConstraint!
@IBOutlet weak var viewBottomConstraint: NSLayoutConstraint!
// MARK: - View Controller Lifecycle
override func viewDidLoad()
super.viewDidLoad()
// Register to listen for keyboard notifications
NotificationCenter.default.addObserver(self, selector: #selector(keyboardIsShowing(notification:)), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardIsHiding(notification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
// Check if there's a model
// If so, then fetch the meta data for that place
if let actualModel = model
// Set delegate to self
actualModel.delegate = self
// Call the get meta function
actualModel.getMeta()
override func viewWillDisappear(_ animated: Bool)
if let actualModel = model
actualModel.closeObserver()
override func didReceiveMemoryWarning()
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
// MARK: - Display
func displayMetaData()
// Check if there's a place object in the property
if place == nil
return
// Set image
model?.getImage(imageName: place!.detailImageName)
// Set name label
nameLabel.text = place!.name
// Set the category label
categoryLabel.text = place!.type
// Set description
if type(of: currentViewController!) == DescriptionChildViewController.self
(currentViewController as? DescriptionChildViewController)?.setDescriptionLabel(text: place!.desc)
else if type(of: currentViewController!) == ReviewsChildViewController.self
// In case the Reviews Child View Controller is already displayed,
// We call this function to set the new data and refresh the table
let reviewsVC = currentViewController as! ReviewsChildViewController
reviewsVC.reloadReviewsData(newReviewData: place!.reviews)
// See if this place is faved
setFaveButtonIcon()
// MARK: - Navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?)
// Set the currentViewController property to the Description Child View Controller
// because that's the first one that is shown in the container view
currentViewController = segue.destination
@IBAction func sectionButtonTapped(_ sender: UIButton)
// Declare a variable to hold the destination VC
var toVC:UIViewController?
// Set section button colors to white
descriptionSectionButton.setTitleColor(UIColor.white, for: .normal)
reviewsSectionButton.setTitleColor(UIColor.white, for: .normal)
writeReviewSectionButton.setTitleColor(UIColor.white, for: .normal)
// Set active button color
sender.setTitleColor(UIColor.blue, for: .normal)
// See which tag triggered this
switch sender.tag
case 1:
// Description button tapped
// Create an instance of the Description Child View Controller
toVC = storyboard?.instantiateViewController(withIdentifier: "DescriptionChildVC")
if let descVC = toVC, let actualPlace = place
(descVC as! DescriptionChildViewController).descText = actualPlace.desc
case 2:
// Reviews button tapped
// Create an instance of the Description Child View Controller
toVC = storyboard?.instantiateViewController(withIdentifier: "ReviewsChildVC")
if let reviewsVC = toVC, let actualPlace = place
(reviewsVC as! ReviewsChildViewController).reviews = actualPlace.reviews
case 3:
// Write a review button tapped
// Create an instance of the Description Child View Controller
toVC = storyboard?.instantiateViewController(withIdentifier: "WriteReviewChildVC")
if let writeReviewsVC = toVC
(writeReviewsVC as! WriteReviewChildViewController).delegate = self
default:
// Description button tapped
// Create an instance of the Description Child View Controller
toVC = storyboard?.instantiateViewController(withIdentifier: "DescriptionChildVC")
// Call SwitchChildViewControllers if currentViewController and toVC are not nil
if let destinationVC = toVC, let currentVC = currentViewController
switchChildViewControllers(fromVC: currentVC, toVC: destinationVC)
func switchChildViewControllers(fromVC:UIViewController, toVC:UIViewController)
// Tell the current VC that its transitioning
fromVC.willMove(toParentViewController: nil)
// Add the new VC
self.addChildViewController(toVC)
containerView.addSubview(toVC.view)
// Size the frame of the toVC
toVC.view.frame = containerView.bounds
// Set the new VC alpha to 0
toVC.view.alpha = 0
// Animate the new VC alpha to 1 and the old VC alpha to 0
UIView.animate(withDuration: 0.5, animations:
toVC.view.alpha = 1
fromVC.view.alpha = 0
) (Bool) in
// Remove the old VC
fromVC.view.removeFromSuperview()
fromVC.removeFromParentViewController()
// Tell the new VC that it has transitioned
toVC.didMove(toParentViewController: self)
// Set the currentViewController property to toVC
self.currentViewController = toVC
// MARK: - Button Action Functions
@IBAction func backButtonTapped(_ sender: UIButton)
// Navigate back to the list
presentingViewController?.dismiss(animated: true, completion: nil)
@IBAction func shareButtonTapped(_ sender: UIButton)
if place == nil
return
// Data items array
var activityItems = [Any]()
// Get the image
let imageData = CacheManager.getImageFromCache(imageName: place!.detailImageName)
if let actualImageData = imageData
// Since we have the image data, create a UIImage
let image = UIImage(data: actualImageData)
if image != nil
activityItems.append(image!)
// Add the description to the activity items
activityItems.append(place!.desc)
// Create a UIActivityViewController
let activityVC = UIActivityViewController(activityItems: activityItems, applicationActivities: nil)
// Present it
present(activityVC, animated: true, completion: nil)
@IBAction func routeButtonTapped(_ sender: UIButton)
if place == nil
return
// Create a url
let modifiedAddress = place!.addr.replacingOccurrences(of: " ", with: "+")
let url = URL(string: "http://maps.apple.com/?address=" + modifiedAddress)
if let actualURL = url
// Open url
UIApplication.shared.open(actualURL, options: [:], completionHandler: nil)
@IBAction func favButtonTapped(_ sender: UIButton)
if place != nil
CacheManager.toggleFave(placeId: place!.id)
setFaveButtonIcon()
// MARK: - Helper Functions
func setFaveButtonIcon()
if CacheManager.isFave(placeId: place!.id)
faveButton.setImage(#imageLiteral(resourceName: "Bookmark Ribbon Filled"), for: .normal)
else
faveButton.setImage(#imageLiteral(resourceName: "Bookmark Ribbon"), for: .normal)
// MARK: - DetailModelDelegate methods
func detailModel(metaDataFor place: Place)
// Set the place property
self.place = place
// Display the meta data in the views
displayMetaData()
func detailModel(imageName: String, imageData: Data)
// Detail model has returned with image data
// Now can set image view
let image = UIImage(data: imageData)
if let actualImage = image
placeImageView.image = actualImage
func detailModelSaveReviewError()
// Show the error alert
let alertController = UIAlertController(title: "Error", message: "There was an error saving your review", preferredStyle: .alert)
let okAction = UIAlertAction(title: "Ok", style: .default, handler: nil)
alertController.addAction(okAction)
present(alertController, animated: false, completion: nil)
func detailModelSaveReviewSuccess()
// Show the reviews child vc
sectionButtonTapped(reviewsSectionButton)
// MARK: - WriteReviewChildViewControllerDelegate Methods
func saveReview(name: String, text: String)
// Child view controller is calling save review
// Pass that data to the detail model
if let actualModel = model
// Call saveReview of the detailmodel
actualModel.saveReview(name, text)
@objc func keyboardIsShowing(notification:NSNotification)
let userInfo = notification.userInfo
if let userInfoDictionary = userInfo
let keyboardRect = userInfoDictionary["UIKeyboardFrameEndUserInfoKey"] as! CGRect
// Animate the constraints
view.layoutIfNeeded()
UIView.animate(withDuration: 0.25)
self.viewTopConstraint.constant = keyboardRect.height * -1
self.viewBottomConstraint.constant = keyboardRect.height
self.view.layoutIfNeeded()
@objc func keyboardIsHiding(notification:NSNotification)
// Animate the constraints
view.layoutIfNeeded()
UIView.animate(withDuration: 0.25)
self.viewTopConstraint.constant = 0
self.viewBottomConstraint.constant = 0
self.view.layoutIfNeeded()
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?)
// Call the "hide keyboard" function of the write reviews child view controller
if type(of: currentViewController!) == WriteReviewChildViewController.self
(currentViewController as! WriteReviewChildViewController).hideKeyboard()
【问题讨论】:
【参考方案1】:过去是什么让我头疼。
-
确保插座已正确连接。我不得不删除并重新连接。
确保单元格样式设置为详细信息。
确保单元格标识符设置为“单元格”。
有时我不得不删除单元格并重新创建以解决问题。
希望这会有所帮助。
【讨论】:
谢谢 - segue 仍在工作,但现在返回“线程 1:致命错误:索引超出范围”以上是关于将结果从 Swift 数组传递到 Segue 到描述的主要内容,如果未能解决你的问题,请参考以下文章
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