Swift中未搜索时隐藏UITableView及搜索时移除多余行问题求助

Hey there! Let's tackle your two issues one by one—hiding the table view initially and getting rid of those extra rows in your search results.

1. Hide UITableView Initially & Toggle Visibility Properly #

First, let's make sure the table view stays hidden until a search is initiated. Here's what to adjust:

Step 1: Set Initial Hidden State #

Add this to your viewDidLoad to hide the table view right when the screen loads:

override func viewDidLoad() {
    super.viewDidLoad()
    // Hide the table view initially
    searchTableView.isHidden = true
    // Don't forget to set up delegates
    searchTextField.delegate = self
    searchTableView.dataSource = self
    searchTableView.delegate = self
}

Step 2: Update Visibility Based on Search Input #

Fix your filterText function to show/hide the table view based on whether there are search results, and handle empty search input correctly:

func filterText(_ query: String){
    searchedArray.removeAll()
    
    // Only filter if the query isn't empty
    if !query.isEmpty {
        for str in LocationData {
            if str.lowercased().starts(with: query.lowercased()){
                searchedArray.append(str)
            }
        }
    }
    
    // Show table view only if there are search results
    searchTableView.isHidden = searchedArray.isEmpty
    searchTableView.reloadData()
}

Step 3: Fix Text Field Text Calculation #

Your original shouldChangeCharactersIn method had a bug when deleting text—let's correct how we calculate the updated search text:

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
    guard let currentText = textField.text else { return true }
    // Correctly compute the updated text after the edit
    let updatedText = (currentText as NSString).replacingCharacters(in: range, with: string)
    
    filterText(updatedText)
    return true
}

2. Eliminate Extra Rows in UITableView #

The extra rows are caused by inconsistent logic in numberOfRowsInSection. Let's simplify this by removing the confusing filtered variable and basing row count directly on search state:

Update Row Count Logic #

func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    // Only return rows if there's active search text and results
    guard let searchText = searchTextField.text, !searchText.isEmpty else {
        return 0
    }
    return searchedArray.count
}

Simplify Cell Configuration #

Since we now only show the table view when there are valid search results, you can clean up cellForRowAt:

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
    cell.textLabel?.text = searchedArray[indexPath.row]
    return cell
}

Bonus: Hide Table After Selecting a Result #

Make sure to hide the table view and dismiss the keyboard when a user selects a location:

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    searchTextField.text = searchedArray[indexPath.row]
    searchTableView.isHidden = true
    searchTextField.resignFirstResponder() // Hide keyboard
}

With these changes, your table view will stay hidden until a user types a search query with matching results, and you won't see any extra rows cluttering the table.

内容的提问来源于stack exchange，提问作者gul Ranaa