我尝试在异步调用中加载搜索结果，因此搜索文本不会花费太多时间进入。
它适用于viewDidLoad但是当我在搜索栏文本上调用相同的方法时，它会通过重新加载数据但不反映在UI上。当我点击搜索栏的取消按钮时会反映出来。我需要在searchBar上输入的每个搜索文本上反映reloadData。
我试过以下代码：非常感谢任何帮助。
import Foundation
import UIKit
class NSOperations {
lazy var downloadQueue:NSOperationQueue = {
var queue = NSOperationQueue()
queue.name = "Image Download queue"
queue.maxConcurrentOperationCount = 1
return queue
}()
lazy var filtrationQueue:NSOperationQueue = {
var queue = NSOperationQueue()
queue.name = "Search Filtration queue"
queue.maxConcurrentOperationCount = 1
return queue
}()
}
class SearchResultController: UIViewController, UITableViewDataSource, UITableViewDelegate,UISearchDisplayDelegate, UISearchBarDelegate
{
@IBOutlet var searchBar: UISearchBar!
@IBOutlet weak var contactsTableView: UITableView!
var genericArr = [Generic]()
var utility = Utility()
var constants = Constants()
var netUtil = NetworkUtil()
var controllerUtil = ControllerUtil()
var parser = Parsers()
var searchString = ""
var filteredTableData = [Generic]()
var searchActive : Bool = false
let pendingOperations:NSOperations = NSOperations()
override func viewDidLoad()
{
super.viewDidLoad()
self.contactsTableView.delegate = self
self.contactsTableView.dataSource = self
self.searchBar.delegate = self
}
func searchBarTextDidBeginEditing(searchBar: UISearchBar) {
searchActive = true;
}
func searchBarTextDidEndEditing(searchBar: UISearchBar) {
searchActive = false
}
func searchBar(searchBar: UISearchBar, textDidChange searchText: String) {
filteredTableData.removeAll(keepCapacity: false)
self.filteredTableData = [Generic]()
if searchText != ""
{
searchActive = true
self.suspendAllOperations()
self.search(searchText)
}
else
{
searchActive = false
}
}
func searchBarCancelButtonClicked(searchBar: UISearchBar) {
searchActive = false
self.searchBar.resignFirstResponder()
}
func tableView(tableView:UITableView, numberOfRowsInSection section:Int) -> Int {
var count:Int = 0
if self.searchActive == true {
count = self.filteredTableData.count
}
else{
count = self.genericArr.count
}
return count
}
func tableView(tableView:UITableView, cellForRowAtIndexPath indexPath:NSIndexPath) -> UITableViewCell {
let resultCell = self.contactsTableView.dequeueReusableCellWithIdentifier("ResultCell") as! ResultCell
var result:Generic = Generic()
if searchActive == true && self.filteredTableData.count > 0
{
result = self.filteredTableData[indexPath.row]
resultCell.setResultCell(result)
}
else
{
result = self.genericArr[indexPath.row]
resultCell.setResultCell(result)
}
return resultCell
}
func suspendAllOperations () {
pendingOperations.downloadQueue.suspended = true
pendingOperations.filtrationQueue.suspended = true
}
func resumeAllOperations () {
pendingOperations.downloadQueue.suspended = false
pendingOperations.filtrationQueue.suspended = false
}
func search(searchTxt: String){
let searchUrl: String = "\(constants.SERVER_URL)\(constants.SEARCH_RESULT_URL)\(searchTxt.stringByAddingPercentEncodingWithAllowedCharacters(NSCharacterSet.URLQueryAllowedCharacterSet())!)"
pendingOperations.filtrationQueue.addOperationWithBlock({
self.netUtil.callJSONData(searchUrl) {(dataDictionary) -> Void in
self.errorStr = dataDictionary[self.constants.defaultsKeys.RESPONSE_ERROR] as! String
let data: AnyObject? = dataDictionary[self.constants.defaultsKeys.RESPONSE_RESULT]
if(self.errorStr.isEmpty || self.errorStr==""){
if data != nil {
if let jsonNSData = data as? NSData
{
if let resultDict :NSDictionary = (try! NSJSONSerialization.JSONObjectWithData(jsonNSData, options: NSJSONReadingOptions.MutableContainers)) as? NSDictionary{
self.loadData(resultDict)
print("count >> \(self.genericArr.count)")
dispatch_async(dispatch_get_main_queue()) {
self.contactsTableView.reloadData()
}
}
}
}
else{
// self.showError("something is wrong happened")
}
}
else{
// self.showError(self.errorStr)
}
}
})
}
func loadData(resultDict : NSDictionary){
let genArray:[Generic] = parser.getGenericArr(resultDict)
if searchActive == true{
self.filteredTableData = [Generic]()
self.filteredTableData.appendContentsOf(genArray)
}
else{
self.genericArr = [Generic]()
self.genericArr.appendContentsOf(genArray)
}
}
func callJSONData(urlStr: String, callback: ((data: Dictionary<String,AnyObject>) -> Void)!)
{
let url = NSURL(string: urlStr)!
var dict = Dictionary<String,AnyObject>()
var errorStr = ""
if let data = NSData(contentsOfURL: url) {
dict = Dictionary<String,AnyObject>()
self.parser.getJSONResultDataDictionary(data) {(dataDictionary) -> Void in
errorStr = dataDictionary[self.constants.defaultsKeys.RESPONSE_ERROR] as! String
if(errorStr.isEmpty || errorStr==""){
if let dataDict = dataDictionary[self.constants.defaultsKeys.RESPONSE_RESULT] as? Dictionary<String,AnyObject>
{
dict = dataDict
dict[self.constants.defaultsKeys.RESPONSE_ERROR] = errorStr
}
else{
dict[self.constants.defaultsKeys.RESPONSE_ERROR] = errorStr
}
}
else
{
dict[self.constants.defaultsKeys.RESPONSE_ERROR] = errorStr
}
}
}
else{
dict = Dictionary<String,AnyObject>()
dict[self.constants.defaultsKeys.RESPONSE_ERROR] = errorStr
}
callback(data: dict)
}
}