ios - UISearchController 显示不正确的结果

Question

我的应用程序包含 UITableViewController、两个 UIViewController 和 Core Data。我想第一次制作 UISearchController。我查看了这个主题的其他问题，但我的 UISearchController 工作不正确。当我写入 searchBar 时，它给出了错误的结果。而且我不知道如何在表格 View 单元格中显示它们。请帮助我。

我在 UITableViewController 中的代码

var resultSearchController: UISearchController!
var searchPredicate: NSPredicate?
var filteredObjects: [Note]? = nil

override func viewDidLoad() {
    super.viewDidLoad()

    self.navigationItem.leftBarButtonItem = self.editButtonItem()

    fetchedResultsController = NSFetchedResultsController(fetchRequest: allEmployeesFetchRequest(), managedObjectContext: managedObjectContext!, sectionNameKeyPath: "mynote", cacheName: "mynote") // both mynote
    fetchedResultsController?.delegate = self
    fetchedResultsController?.performFetch(nil)

    // UISearchController setup
    self.resultSearchController = ({
        let controller = UISearchController(searchResultsController: nil)
        controller.delegate = self
        controller.searchResultsUpdater = self
        controller.hidesNavigationBarDuringPresentation = false
        controller.dimsBackgroundDuringPresentation = true
        controller.searchBar.sizeToFit()
        controller.searchBar.delegate = self
                    self.tableView.tableHeaderView = controller.searchBar
        return controller
    })()
    self.tableView.reloadData()
}

func updateSearchResultsForSearchController(searchController: UISearchController) {
    let searchText = self.resultSearchController.searchBar.text
    println(searchText)
    if let searchText = searchText {
       searchPredicate = NSPredicate(format: "mynote contains[c] %@", searchText)
        filteredObjects = self.fetchedResultsController?.fetchedObjects?.filter() {
            return self.searchPredicate!.evaluateWithObject($0)
        } as! [Note]?
        self.tableView.reloadData()
        println(searchPredicate)
    }
}

和

override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
    if searchPredicate == nil {
        return fetchedResultsController?.sections?.count ?? 0
    } else {
        return 1
    }
}

override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    if searchPredicate == nil {
        return fetchedResultsController?.sections?[section].numberOfObjects ?? 0 //0 default
    } else {
        return filteredObjects?.count ?? 0
    }
}

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCellWithIdentifier("CellNote", forIndexPath: indexPath) as! UITableViewCell
    if searchPredicate == nil {
        if var cellContact = fetchedResultsController?.objectAtIndexPath(indexPath) as? Note {
            cell.textLabel?.text = cellContact.mynote
            cell.detailTextLabel?.text = cellContact.mytime
            return cell
        }
    }
    return cell
}

我的核心数据类有

import Foundation
import CoreData
@objc(Note)
class Note: NSManagedObject {

    @NSManaged var mynote: String
    @NSManaged var mytime: String

}

Answer 1

我有一个用于多个查询的类，我只传递一个谓词，有时是一个排序，然后返回实体类对象的数组。

class QueryDatabase: NSObject {
    private var _managedObjectContext: NSManagedObjectContext?

    init(managedObjectContext: NSManagedObjectContext){
       super.init()
       _managedObjectContext = managedObjectContext
    }

    func QueryTable(entityName: String, sortBy: String?, ascending: Bool, searchPredicate: NSPredicate?) -> AnyObject?{
        if _managedObjectContext != nil {
            let fetchRequest = NSFetchRequest(entityName: entityName)
            if(sortBy != nil){
                let sort = NSSortDescriptor(key: sortBy!, ascending: ascending)
                fetchRequest.sortDescriptors = [sort]
            }

            if(searchPredicate != nil){
                fetchRequest.predicate = searchPredicate!
            }

            var err: NSError?
            if let fetchResults = _managedObjectContext!.executeFetchRequest(fetchRequest, error: &err){
                return fetchResults
            }else{
                NSLog("ERROR:\(err?.description)")
            }
        }
        return nil
    }
}

我将它与 searchBar 结合使用，但在我的例子中，我的谓词在其定义上添加了另一个修饰符 [cd]:

func findPricesBySearchCriteria(searchCriteria: String) -> [Prices]{
    if(_managedObjectContext != nil){
        let queryDatabase = QueryDatabase(managedObjectContext: _managedObjectContext!)
        if let results = queryDatabase.QueryTable("Prices", sortBy: "item_description", ascending: true, searchPredicate:  NSPredicate(format: "item_description contains[cd] %@", searchCriteria)) as? [Prices]{
            arrSearch = results
        }
    }
    return arrSearch
}