我已经实现了一个搜索栏来搜索用户,但是当我搜索某些内容时,表格 View 中没有显示任何内容。我在下面附上了我的 View Controller 的图片。
View Controller :
这个 View Controller 显示所有用户的列表,搜索栏应该帮助用户找到用户名。
import UIKit
class FindFriendsViewController: UIViewController {
var users = [User]()
@IBOutlet weak var tableView: UITableView!
@IBOutlet weak var searchBar: UISearchBar!
var searchItem = [String]()
var searching = false
override func viewDidLoad() {
super.viewDidLoad()
tableView.tableFooterView = UIView()
tableView.rowHeight = 71
let tap = UITapGestureRecognizer(target: self.view, action: #selector(UIView.endEditing(_:)))
tap.cancelsTouchesInView = false
self.view.addGestureRecognizer(tap)
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
UserService.usersExcludingCurrentUser { [unowned self] (users) in
self.users = users
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
}
extension FindFriendsViewController: UITableViewDataSource {
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if searching {
return searchItem.count
} else {
return users.count
}
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "FindFriendsCell") as! FindFriendsCell
//让user = users[indexPath.row]
var usernamesArr = [String]()
for user in users {
usernamesArr.append(user.username)
}
if searching {
cell.textLabel?.text = searchItem[indexPath.row]
} else {
cell.textLabel?.text = usernamesArr[indexPath.row]
cell.delegate = self
configure(cell: cell, atIndexPath: indexPath)
}
return cell
}
func configure(cell: FindFriendsCell, atIndexPath indexPath: IndexPath) {
let user = users[indexPath.row]
cell.usernameLabel.text = user.username
cell.followButton.isSelected = user.isFollowed
}
extension FindFriendsViewController: FindFriendsCellDelegate {
func didTapFollowButton(_ followButton: UIButton, on cell: FindFriendsCell) {
guard let indexPath = tableView.indexPath(for: cell) else { return }
followButton.isUserInteractionEnabled = false
let followee = users[indexPath.row]
FollowService.setIsFollowing(!followee.isFollowed, fromCurrentUserTo: followee) { (success) in
defer {
followButton.isUserInteractionEnabled = true
}
guard success else { return }
followee.isFollowed = !followee.isFollowed
self.tableView.reloadRows(at: [indexPath], with: .none)
}
}
extension FindFriendsViewController: UISearchBarDelegate {
func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
var usernamesArr = [String]()
for user in users {
usernamesArr.append(user.username)
}
searchItem = usernamesArr.filter({$0.lowercased().prefix(searchText.count) == searchText.lowercased()})
searching = true
tableView.reloadData()
}
最佳答案
我正在考虑您的代码中可能出现的不同问题。您需要设置搜索栏委托(delegate)和搜索结果更新程序:
yourSearchController.searchBar.delegate = self
yourSearchController.searchResultsUpdater = self
如果你没有 Controller ,直接搜索栏:
yourSearchBar.delegate = self
yourSearchBar.searchResultsUpdater = self
作为您的委托(delegate)人:
extension MasterViewController: UISearchBarDelegate {
// MARK: - UISearchBar Delegate
func searchBar(_ searchBar: UISearchBar, selectedScopeButtonIndexDidChange selectedScope: Int) {
filterContentForSearchText(searchBar.text!, scope: searchBar.scopeButtonTitles![selectedScope])
}
}
extension MasterViewController: UISearchResultsUpdating {
// MARK: - UISearchResultsUpdating Delegate
func updateSearchResults(for searchController: UISearchController) {
let searchBar = searchController.searchBar
let scope = searchBar.scopeButtonTitles![searchBar.selectedScopeButtonIndex]
filterContentForSearchText(searchController.searchBar.text!, scope: scope)
}
或者您可能缺少更新之类的东西。检查排除问题的数据路径时间。首先,您在搜索栏中输入文本,然后检查文本所在的代码以及发生的情况。当搜索栏处于结束编辑状态时,您是否更新了表格 View ?
如果它对您没有帮助,请查看我之前学习过的精彩教程:Search Bar iOS
关于ios - 搜索栏在 Swift 4 IOS App 中不起作用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/55445156/