在Swift中使用搜索栏搜索Firebase数据

Question

我正在尝试使用我的应用程序中的UISearchBar来搜索我的Firebase数据，但我被卡住了。我已在表格视图中成功从Firebase接收数据。我希望用户成为一个通过releaseName和/或releaseType搜索“发布”的人。

Firebase数据结构

视图控制器

import UIKit
import FirebaseDatabase
import SDWebImage
import SwiftyGif



class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource, UISearchResultsUpdating, SwiftyGifDelegate {

var refReleases: DatabaseReference!

var releasesData = [ReleaseModel]()

public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
    let cell = tableView.dequeueReusableCell(withIdentifier: "ReleaseCell", for: indexPath) as! ReleaseTableViewCell
    var release: ReleaseModel
    release = releasesData[indexPath.row]

    cell.releaseType.text = release.releasetype
    cell.releaseName.text = release.releasename
    cell.releasePrice.text = release.releaseprice
    cell.releaseDate.text = release.releasedate
    cell.releaseImage.sd_setImage(with: URL(string: release.releaseimage!), placeholderImage: UIImage(named: "placeholder1"))

    return cell
}

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

public func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    let release = releasesData[indexPath.row]
    performSegue(withIdentifier: "ReleasesToWebviews", sender: release)
}

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    var wbVC: WebviewsViewController = segue.destination as! WebviewsViewController
        }

override func viewDidLoad() {
    super.viewDidLoad()

    allButton.setImage(UIImage(named:"selectedall"), for: .normal)

    searchBarController.searchResultsUpdater = self
    searchBarController.dimsBackgroundDuringPresentation = false
    definesPresentationContext = true


    view.addSubview(logoAnimationView)
    logoAnimationView.pinEdgesToSuperView()
    logoAnimationView.logoGifImageView.delegate = self

    // Remove title from back button. Now only "<" symbol will be show as back button.
    let backButton = UIBarButtonItem(title: "", style: .plain, target: nil, action: nil)
    self.navigationItem.backBarButtonItem = backButton

    // Do any additional setup after loading the view, typically from a nib.
    //Search bar
    self.navigationItem.searchController = searchBarController
    navigationItem.hidesSearchBarWhenScrolling = false
    searchBarController.searchBar.tintColor = UIColor.white
    searchBarController.searchBar.barTintColor = UIColor.white
    let placeholderAppearance = UITextField.appearance(whenContainedInInstancesOf: [UISearchBar.self])
    placeholderAppearance.font = UIFont(name: "Avenir", size: 16)
    UITextField.appearance(whenContainedInInstancesOf: [UISearchBar.self]).attributedPlaceholder = NSAttributedString(string: "Search for brand, color, etc.", attributes: [NSAttributedString.Key.foregroundColor: UIColor.orange])
    if let textfield = searchBarController.searchBar.value(forKey: "searchField") as? UITextField {
        if let backgroundview = textfield.subviews.first {

            // Background color
            backgroundview.backgroundColor = UIColor.white

            // Rounded corner
            backgroundview.layer.cornerRadius = 10;
            backgroundview.clipsToBounds = true;
        }
    }
    //Retrieving data from Firebase
    refReleases = Database.database().reference().child("releases");
    refReleases.observe(DataEventType.value) { (snapshot) in

        if snapshot.childrenCount>0{
            self.releasesData.removeAll()

        for releases in snapshot.children.allObjects as![DataSnapshot]{
            let releaseObject = releases.value as? [String: AnyObject]
            let releaseName = releaseObject?["releaseName"]
            let releaseType = releaseObject?["releaseType"]
            let releasePrice = releaseObject?["releasePrice"]
            let releaseDate = releaseObject?["releaseDate"]
            let releaseImage = releaseObject?["releaseImage"]

            let release = ReleaseModel(releasetype: releaseType as! String?, releasename: releaseName as! String?, releaseprice: releasePrice as! String?, releasedate: releaseDate as! String?, releaseimage: releaseImage as! String?)
            self.releasesData.append(release)
        }

        self.tableView.reloadData()
    }

}
}

ReleaseModel.swift

class ReleaseModel: NSObject{

var releasetype: String?
var releasename: String?
var releaseprice: String?
var releasedate: String?
var releaseimage: String?

init(releasetype:String?, releasename:String?, releaseprice:String?, releasedate:String?, releaseimage:String?) {
    self.releasetype = releasetype
    self.releasename = releasename
    self.releaseprice = releaseprice
    self.releasedate = releasedate
    self.releaseimage = releaseimage
}
}

ReleaseTableViewCell.swift

import UIKit
import OneSignal

class ReleaseTableViewCell: UITableViewCell {

@IBOutlet weak var releaseType: UILabel!
@IBOutlet weak var releaseName: UILabel!
@IBOutlet weak var releasePrice: UILabel!
@IBOutlet weak var releaseDate: UILabel!
@IBOutlet weak var releaseImage: UIImageView!
@IBOutlet weak var notifyButton: UIButton!

@IBAction func tapButton(_ sender: UIButton) {
    // Call when you want to prompt the user to accept push notifications.
    // Only call once and only if you set kOSSettingsKeyAutoPrompt in AppDelegate to false.
    OneSignal.promptForPushNotifications(userResponse: { accepted in
        print("User accepted notifications: \(accepted)")
    })
    sender.isSelected = !sender.isSelected
    UserDefaults.standard.set(sender.isSelected, forKey: "isSaved")
    if (UserDefaults.standard.bool(forKey: "isSaved") == sender.isSelected) {
        OneSignal.sendTag("notificationtest", value: "true")
    }
    OneSignal.deleteTag("notificationtest")
}

override func awakeFromNib() {
    super.awakeFromNib()
    // Initialization code
    //Set button image
    notifyButton.setImage(UIImage(named: "notifybutton"), for: .normal)
    notifyButton.setImage(UIImage(named: "notifiedbutton"), for: .selected)
    notifyButton.isSelected = UserDefaults.standard.bool(forKey: "isSaved")
}

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

    // Configure the view for the selected state
}

}