搜索栏不刷新 UIbutton 颜色

Question

这是我的头疼...希望有人有药。

情况 - 我有一个链接到下面的表格视图的搜索栏 - Tableview 单元由 1 个标签和 1 个按钮组成 - 该按钮是链接到 coredata 的“收藏”按钮 - 如果标签的文本确实存在于 coredata 中，则其颜色为棕色 - 如果 coredata 中不存在该文本，则其颜色为灰色。按下的话变成棕色，并且在coredata中注册了lable的文字

头痛 - 一切都非常适合第一次过滤（一切都到位，按钮颜色正确显示文本是否已注册或未注册，并且通过单击按钮进行注册非常好但是...... - 当搜索发生变化时，单元格被完全（未）过滤，但不是按钮：那些应该显示为灰色的单元格显示为棕色 - 如果我更换屏幕并返回，一切都会重置并且按钮颜色正常

我不知道如何在搜索过程中刷新按钮的标题颜色。按钮的标题是文本。有什么提示吗？

CellForRowAt 中的代码

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

    let cell = searchTbv.dequeueReusableCell(withIdentifier: "searchCell", for: indexPath) as! SearchTbvCell

    if searhing {
        cell.searchLbl.text = mySearch[indexPath.row]
    }
    else {
        cell.searchLbl.text = dataSearch.searchItem[indexPath.row]
    }

    return cell
}

搜索栏代码

extension SearchVC: UISearchBarDelegate {

func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {

    searhing = true

    mySearch = dataSearch.searchItem.filter({$0.lowercased().folding(options: .diacriticInsensitive, locale: .current).prefix(searchText.count) == searchText.lowercased()})

    searchTbv.reloadData()

}

func searchBarCancelButtonClicked(_ searchBar: UISearchBar) {
    searhing = false
    searchBar.text = ""
    searchTbv.reloadData()

}

设置按钮颜色的代码（位于自定义单元格类中的代码）：

class SearchTbvCell: UITableViewCell {

//MARK: OUTLETS
@IBOutlet weak var searchLbl: UILabel!
@IBOutlet weak var searchBtn: UIButton!

override func awakeFromNib() {
    super.awakeFromNib()
    fetchFromCoreData()
}

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


@IBAction func favoriteBtnTapped(_ sender: UIButton) {

    // Set fav button color to brown if selected/tapped
    searchBtn.setTitleColor(.brown, for: .normal)

    // Permanently record selection as favorite into coredata
    recordPermanently()
}



//MARK: METHODS

// Fetch contents from CoreData and up-date button's color consequently
func fetchFromCoreData () {
    // Create a reference to container
    let appDelegate = UIApplication.shared.delegate as? AppDelegate
    // Create a context from the container
    let managedContext = appDelegate?.persistentContainer.viewContext
    // Prepare a request and sorting
    let myRequest = NSFetchRequest<NSFetchRequestResult>(entityName: "MyFavorites")
    myRequest.predicate = NSPredicate(format:"favoriteWines = %@", searchLbl.text!)
    do {
        let results = (try managedContext?.fetch(myRequest))!
        for _ in results {
            searchBtn.setTitleColor(.brown, for: .normal)
        }
    }
    catch{}
}


// Record permanently in core data and changethe button's color
func recordPermanently(){
    // Create a reference to container
    guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else {return}
    // Create a context from the container
    let managedContext = appDelegate.persistentContainer.viewContext
    // Create an entity to manage records
    let recordEntity = NSEntityDescription.entity(forEntityName: "MyFavorites", in: managedContext)!
    // Create a new record
    let newRecord = NSManagedObject(entity: recordEntity, insertInto: managedContext)
    // Pass values to new record
    newRecord.setValue(searchLbl.text!, forKeyPath: "favoriteWines")
    // Save record
    do {
        try managedContext.save()
        searchBtn.setTitleColor(.brown, for: .normal)
    }
    catch let error as NSError{
        print("Failed to save permanently. \(error), \(error.userInfo)" )
    }
}

}

Answer 1

我最终可以通过将 cell.searchBtn.setTitleColor(.lightGray, for: .normal) 添加到 cellForRowAt 代码（如下所示）来解决这个问题。

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

    let cell = searchTbv.dequeueReusableCell(withIdentifier: "searchCell", for: indexPath) as! SearchTbvCell

    if searhing {
        cell.searchLbl.text = mySearch[indexPath.row]
        cell.searchBtn.setTitleColor(.lightGray, for: .normal) // This line has fixed the problem

        if cell.searchLbl.text == myProperties.isInCoreData {
            cell.searchBtn.setTitleColor(.brown, for: .normal)
        }
        else {
            cell.searchBtn.setTitleColor(.lightGray, for: .normal)
        }
    }
    else {
        cell.searchLbl.text = dataSearch.searchItem[indexPath.row]
        cell.searchBtn.setTitleColor(.lightGray, for: .normal) // This line has fixed the problem
    }

    return cell
}

Answer 2

免责声明：在浏览器中输入，未在 Xcode 中测试

您尚未指明在何处以及如何设置按钮的颜色，但我建议您在 willDisplayCell 中执行此操作：

func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell,  forRowAt indexPath: IndexPath) {
    if cell.label.text.existsInCoreCata() {
         cell.button.setTitleColor(.brown, for: .normal)
    }
    else {
        cell.button.setTitleColor(.grey, for: .normal)
    }
}

existsInCoreCata() 是您检查标签是否存在于 CoreData 中的代码。