Ios 如何在tableView加载单元格上显示微调器/指示器

您好，我在一些应用程序中看到，当用户搜索某个内容时，在tableview单元格上显示微调器或活动指示器，但该单元格未填充值。这很难解释，但就像我在搜索栏中键入了什么，结果开始根据我键入的关键字在tableview上弹出，spinner开始在单元格上移动。如果前两个值来得快，它会在第三个单元格上显示微调器，只要值开始填满单元格，微调器就会转到下一个空单元格。我怎么能有这种效果。这是我搜索城市和国家的代码

class CountryTableViewController: UITableViewController, UISearchResultsUpdating {

    var delegate : CountryTableViewControllerDelegate! = nil
    var dict = NSDictionary()
    var filteredKeys = [String]()

    var resultSearchController = UISearchController()

    var newTableData = [String]()

    var departureOrArrivalSegue:Int?

    override func viewDidLoad() {
        super.viewDidLoad()

        self.resultSearchController = ({

            let controller  = UISearchController(searchResultsController: nil)
            controller.searchResultsUpdater = self
            controller.dimsBackgroundDuringPresentation = false
            controller.searchBar.sizeToFit()
            self.tableView.tableHeaderView = controller.searchBar
            self.definesPresentationContext = true
            return controller


        })()

        self.tableView.reloadData()
    }

    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {

        if (self.resultSearchController.active) {

            return self.filteredKeys.count
        } else {

            return dict.count
        }

    }

    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

        let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! CountryTableViewCell

        if(self.resultSearchController.active){

           // let key = self.filteredKeys[indexPath.row]

            //let dictionary = self.dict[key] as! NSDictionary






                let cityName = (((self.dict["\(indexPath.row)"] as?NSDictionary)!["Country"] as?NSDictionary)!["city_name"] as?NSString)

               let stateName  = (((self.dict["\(indexPath.row)"] as?NSDictionary)!["Country"] as? NSDictionary)!["state_name"] as? NSString)

                 let shortName  = (((self.dict["\(indexPath.row)"] as?NSDictionary)!["Country"] as? NSDictionary)!["short_country_name"] as? NSString)


            if (cityName !== "-" || shortName !== "-"){
                cell.stateNameLabel.text = stateName as? String
                cell.cityNameLabel.text = cityName as? String
                 cell.shortNameLabel.text = shortName as? String

            }

                      return cell

        }else{



            if let cityName = (((self.dict["\(indexPath.row)"] as?NSDictionary)!["Country"] as?NSDictionary)!["city_name"] as?NSString){
            cell.cityNameLabel.text = cityName as String
                }
            return cell
        }



    }

    override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {

        let id = Int((((dict["\(indexPath.item)"] as?NSDictionary)!["Country"] as?NSDictionary)!["id"] as?NSString)! as String)

        let cityName = (((dict["\(indexPath.item)"] as?NSDictionary)!["Country"] as?NSDictionary)!["city_name"] as?NSString)! as String

        let countryShortName = (((dict["\(indexPath.item)"] as?NSDictionary)!["Country"] as?NSDictionary)!["short_country_name"] as?NSString)! as String

         delegate.country(id!,cityName: cityName, countryShortName: countryShortName,departureOrArrivalSegue: departureOrArrivalSegue!)

        self.navigationController!.popViewControllerAnimated(true)



    }



    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated);
        self.navigationController?.setNavigationBarHidden(false, animated: true)
    }

    override func viewWillDisappear(animated: Bool) {

        super.viewWillDisappear(animated);
        self.navigationController?.setNavigationBarHidden(true, animated: false)

         self.view.layoutIfNeeded()
    }




    func updateSearchResultsForSearchController(searchController: UISearchController) {
        let searchWord = searchController.searchBar.text!
        getCountriesNamesFromServer(searchWord)
    }



    func getCountriesNamesFromServer(searchWord:String) {
        let url:String = "localhost"
        let params = ["keyword":searchWord]

        ServerRequest.postToServer(url, params: params) { result, error in
            if let result = result {
                print(result)

                self.dict = result

                self.filteredKeys.removeAll()

                for (key, value) in self.dict {
                    let valueContainsCity: Bool = (((value as? NSDictionary)?["Country"] as? NSDictionary)?["city_name"] as? String)?.uppercaseString.containsString(searchWord.uppercaseString) ?? false

                    let valueContainsCountry: Bool = (((value as? NSDictionary)?["Country"] as? NSDictionary)?["country_name"] as? String)?.uppercaseString.containsString(searchWord.uppercaseString) ?? false

                    if valueContainsCity || valueContainsCountry {
                        self.filteredKeys.append(key as! String)
                    }
                }
                  dispatch_async(dispatch_get_main_queue()) {
                self.tableView.reloadData()
                }
            }
        }
}
}

这是一个应用程序，有这样的效果，我需要的

---

这完全取决于您想要的效果，但是您可以添加一个视图，其中微调器作为子视图（因此您可以将其放置在中心位置）作为表视图的页脚。

我所做的是以编程方式添加一个子视图，这样主表在后台，而微调器是集中的。这个例子实际上是在Objective-C中，但是你明白了。它位于

viewDidLoad

方法中：

self.spinner = [[UIActivityIndicatorView alloc]    initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
self.spinner.hidesWhenStopped = YES;
self.spinner.frame = CGRectMake(0, 0, 80, 80);
self.spinner.center = CGPointMake(self.view.bounds.size.width / 2,    self.view.bounds.size.height / 2);
[self.view addSubview:self.spinner];

---

对不起，我不明白。你是说我应该创建一个uiview，在uiview的上面我应该有一个微调器，然后把它放在单元格上？让我给你发送应用截图不，作为表尾，不在任何cellokay上。请检查截图。我刚刚更新了这个问题