问题描述
我正在创建一个消息传递应用程序,用户可以在其中通过 UITableView
选择他们想与谁聊天,问题是显然需要一种方法来搜索特定用户,我已经实现了 UISearchController
,我可以找到我搜索的用户。当我使用 override func tableView(_ tableView: UITableView,didSelectRowAt indexPath: IndexPath)
方法选择用户时,真正的问题就开始了,因为当我选择用户时,由于 indexPath.row
选择了错误的用户。
这是我的一些代码:
NewMessageController:
import UIKit
import Firebase
import FirebaseDatabase
class NewMessageController: UITableViewController,UISearchBarDelegate,UISearchResultsUpdating {
var searchController = UISearchController()
var activityIndicator = UIActivityIndicatorView(style: .large)
var aiView = UIView()
let cellId = "cellId"
var users = [User]()
var filteredUsers = [User]()
override func viewDidLoad() {
super.viewDidLoad()
initSearchController()
setUpActivityIndicator()
navigationItem.leftBarButtonItem = UIBarButtonItem(title: "Cancel",style: .plain,target: self,action: #selector(didTapCancelButton))
tableView.register(UserCell.self,forCellReuseIdentifier: cellId)
startAI()
fetchUser()
}
func initSearchController() {
searchController.loadViewIfNeeded()
searchController.searchResultsUpdater = self
searchController.obscuresBackgroundDuringPresentation = false
searchController.searchBar.enablesReturnKeyAutomatically = false
searchController.searchBar.returnKeyType = UIReturnKeyType.done
definesPresentationContext = true
navigationItem.searchController = searchController
navigationItem.hidesSearchBarWhenScrolling = false
searchController.searchBar.scopeButtonTitles = ["All"]
searchController.searchBar.delegate = self
}
func fetchUser() {
Database.database().reference().child("users").observe(.childAdded,with: { (snapshot) in
if let dictionary = snapshot.value as? [String: AnyObject] {
let user = User(dictionary: dictionary)
user.id = snapshot.key
// user.setValuesForKeys(dictionary)
self.users.append(user)
dispatchQueue.main.async {
self.stopAI()
self.tableView.reloadData()
}
}
},withCancel: nil)
}
func setUpActivityIndicator() {
aiView.layer.zPosition = 0.1
aiView.backgroundColor = UIColor.gray
aiView.alpha = 0
aiView.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(aiView)
aiView.centerXAnchor.constraint(equalTo: tableView.centerXAnchor).isActive = true
aiView.centerYAnchor.constraint(equalTo: tableView.centerYAnchor,constant: -60).isActive = true
aiView.heightAnchor.constraint(equalToConstant: 150).isActive = true
aiView.widthAnchor.constraint(equalToConstant: 150).isActive = true
aiView.layer.masksToBounds = true
aiView.layer.cornerRadius = 15
activityIndicator.layer.zPosition = 0.2
activityIndicator.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(activityIndicator)
activityIndicator.centerXAnchor.constraint(equalTo: aiView.centerXAnchor).isActive = true
activityIndicator.centerYAnchor.constraint(equalTo: aiView.centerYAnchor).isActive = true
}
func startAI() {
activityIndicator.startAnimating()
aiView.alpha = 0.80
tableView.isUserInteractionEnabled = false
}
func stopAI() {
self.activityIndicator.stopAnimating()
self.tableView.isUserInteractionEnabled = true
self.aiView.alpha = 0
}
override func tableView(_ tableView: UITableView,heightForRowAt indexPath: IndexPath) -> CGFloat {
return 100
}
var messagesViewController: MessagesViewController?
override func tableView(_ tableView: UITableView,didSelectRowAt indexPath: IndexPath) {
dismiss(animated: true) {
let selectedUser: User!
if(self.searchController.isActive)
{
selectedUser = self.filteredUsers[indexPath.row]
}
else
{
selectedUser = self.users[indexPath.row]
}
self.messagesViewController?.showChatControllerForUser(user: selectedUser)
}
}
override func tableView(_ tableView: UITableView,numberOfRowsInSection section: Int) -> Int {
if (searchController.isActive) {
return filteredUsers.count
}
return users.count
}
override func tableView(_ tableView: UITableView,cellForRowAt indexPath: IndexPath) -> UITableViewCell {
startAI()
let cell = tableView.dequeueReusableCell(withIdentifier: cellId,for: indexPath) as! UserCell
let thisUser: User!
if (searchController.isActive) {
thisUser = filteredUsers[indexPath.row]
} else {
thisUser = users[indexPath.row]
}
cell.nameLabel.text = "\(thisUser.firstname!) \(thisUser.surname!)"
cell.usernameLabel.text = thisUser.username
cell.profileImageView.loadImageUsingCacheWithUrlString(urlString: thisUser.userImg!)
cell.timeLabel.text = nil
stopAI()
return cell
}
func updateSearchResults(for searchController: UISearchController) {
let searchBar = searchController.searchBar
let scopeButton = searchBar.scopeButtonTitles![searchBar.selectedScopeButtonIndex]
let searchText = searchBar.text!
filterForSearchTextAndScopeButton(searchText: searchText,scopeButton: scopeButton)
}
func filterForSearchTextAndScopeButton(searchText: String,scopeButton : String = "All") {
filteredUsers = users.filter {
user in
let scopeMatch = (scopeButton == "All" || user.username!.lowercased().contains(scopeButton.lowercased()))
if(searchController.searchBar.text != "") {
let searchTextMatch = user.username!.lowercased().contains(searchText.lowercased())
return scopeMatch && searchTextMatch
} else {
return scopeMatch
}
}
tableView.reloadData()
}
}
用户模型:
import UIKit
class User: NSObject {
@objc var id: String?
@objc var firstname: String?
@objc var surname: String?
@objc var email: String?
@objc var username: String?
@objc var userImg: String?
init(dictionary: [String: AnyObject]) {
self.id = dictionary["id"] as? String
self.firstname = dictionary["firstname"] as? String
self.surname = dictionary["surname"] as? String
self.username = dictionary["username"] as? String
self.email = dictionary["email"] as? String
self.userImg = dictionary["userImg"] as? String
}
}
@objc func showChatControllerForUser(user: User) {
let chatLogController = ChatLogController(collectionViewLayout: UICollectionViewFlowLayout())
chatLogController.user = user
navigationController?.pushViewController(chatLogController,animated: true)
}
解决方法
像这样更改检测搜索是否处于活动状态的方式。
override func tableView(_ tableView: UITableView,didSelectRowAt indexPath: IndexPath) {
dismiss(animated: true) {
let selectedUser: User!
if(self.searchController.searchBar.text != "")
{
selectedUser = self.filteredUsers[indexPath.row]
}
else
{
selectedUser = self.users[indexPath.row]
}
self.messagesViewController?.showChatControllerForUser(user: selectedUser)
}
}
有时 searchController 处于活动状态,但 searhbar 是“”,因此无法实现检查搜索词在哪里