ios - NSPredicate 没有正确过滤 TableView

Question

我正在开发提醒应用程序，我遇到了一些问题，其中之一是当用户点击其中一个类别时，表格将根据所选类别重新加载；任务名称和类别已正确重新加载，没有任何问题，但时间和日期未被过滤，如下图所示

我认为下面的代码有问题，我该如何解决这个问题？

ReminderTable.swift

 class ReminderTable: UITableViewController,NSFetchedResultsControllerDelegate{   

        @IBOutlet weak var menuViewRelative: UIView!
        @IBOutlet weak var categroyFilter:UISegmentedControl!
        var reminders:[ReminderData] = []
        var fetchResultController:NSFetchedResultsController!
        let reminderFetch = NSFetchRequest(entityName: "Reminder")
        let managedObjectContext = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext


        override func viewDidLoad() {
            super.viewDidLoad()

            title = "Reminder"
            navigationItem.backBarButtonItem = UIBarButtonItem(title: "", style: .Plain, target: nil, action: nil)




            navigationItem.backBarButtonItem = UIBarButtonItem(title: "", style: .Plain, target: nil, action: nil)

            let fetchRequest = NSFetchRequest(entityName: "Reminder")
            let sortDescriptor = NSSortDescriptor(key:"time", ascending: true)
            fetchRequest.sortDescriptors = [sortDescriptor]


            if let managedObjectContext = (UIApplication.sharedApplication().delegate as? AppDelegate)?.managedObjectContext {

                fetchResultController = NSFetchedResultsController(fetchRequest: fetchRequest, managedObjectContext: managedObjectContext, sectionNameKeyPath: nil, cacheName: nil)
                fetchResultController.delegate = self

                do {
                    try fetchResultController.performFetch()
                    reminders = fetchResultController.fetchedObjects as! [ReminderData]
                } catch {
                    print(error)
                }



            }


                  loadData("All")


             tableView.allowsSelection = false
             self.navigationController!.toolbarHidden = false


        }

        override func viewDidDisappear(animated: Bool) {
            categroyFilter.selectedSegmentIndex = 0
        }




        func loadData(category:String){

            if category == "All"{


                do{
                    let request = NSFetchRequest(entityName:"Reminder")
                    let sortDescriptor = NSSortDescriptor(key:"time", ascending: true)
                    request.sortDescriptors = [sortDescriptor]
                    reminders = try managedObjectContext.executeFetchRequest(request) as! [ReminderData]

                    self.tableView.reloadData()
                }catch{
                    fatalError("error")
                }

            }else{


            do{

                let request = NSFetchRequest(entityName:"Reminder")
                  request.predicate = NSPredicate(format: "category = %@", category)
                reminders = try managedObjectContext.executeFetchRequest(request) as! [ReminderData]
                 self.tableView.reloadData()

            }catch{
                fatalError("error")
            }
            }

          self.tableView.reloadData()
        }



        override func viewWillAppear(animated: Bool) {
            super.viewWillAppear(animated)

            navigationController?.hidesBarsOnSwipe = false
            self.navigationController!.navigationBarHidden = false


        }


        override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
            return 1
        }

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


            return reminders.count
        }

        override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
            let task = fetchResultController.objectAtIndexPath(indexPath)
                as! ReminderData

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

            cell.name.text = reminders[indexPath.row].name
            cell.category.text = reminders[indexPath.row].category
            cell.date.text = task.stringForDate()
            cell.time.text = task.stringForTime()


            return cell
        }

        override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {

            if editingStyle == .Delete {
                // Delete the row from the data source
                reminders.removeAtIndex(indexPath.row)
            }

            tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
        }

        override func tableView(tableView: UITableView, editActionsForRowAtIndexPath indexPath: NSIndexPath) -> [UITableViewRowAction]? {

            let RemoveAction = UITableViewRowAction(style: UITableViewRowActionStyle.Default, title: "Remove",handler: { (action, indexPath) -> Void in


                if let managedObjectContext = (UIApplication.sharedApplication().delegate as? AppDelegate)?.managedObjectContext {


                    let remove  = UIAlertController(title: "Are You Sure You Want Delete this Reminder ?", message: nil, preferredStyle: UIAlertControllerStyle.Alert)

                    let Yes = UIAlertAction(title: "Yes", style: .Default) { (action) in

                        let reminderToDelete = self.fetchResultController.objectAtIndexPath(indexPath) as! ReminderData
                        managedObjectContext.deleteObject(reminderToDelete)

                        do {
                            try managedObjectContext.save()
                        } catch {
                            print(error)
                        }


                    }
                    remove.addAction(Yes)


                    let No = UIAlertAction(title: "No", style: .Destructive) { (action) in
                    }
                    remove.addAction(No)



                    self.presentViewController(remove, animated: true) {}


                }
            })

            let editAction = UITableViewRowAction(style: UITableViewRowActionStyle.Default, title: "Edit",handler: { (action, indexPath) -> Void in

                    tableView.setEditing(false, animated: true)
                let cell = tableView.cellForRowAtIndexPath(indexPath)
                self.performSegueWithIdentifier("editReminder", sender: cell)

            })

            RemoveAction.backgroundColor = UIColor(red: 247/255, green: 93/255, blue: 89/255, alpha: 1)
            editAction.backgroundColor = UIColor(red: 21/255, green: 137/255, blue: 255/255, alpha: 1)
            return [RemoveAction,editAction]
        }

        @IBAction func unwindToHomeScreen(segue:UIStoryboardSegue) {
        }


        func controllerWillChangeContent(controller: NSFetchedResultsController) {
            tableView.beginUpdates()
        }


        func controller(controller: NSFetchedResultsController, didChangeSection sectionInfo: NSFetchedResultsSectionInfo, atIndex sectionIndex: Int, forChangeType type: NSFetchedResultsChangeType) {
            // 1
            switch type {
            case .Insert:
                tableView.insertSections(NSIndexSet(index: sectionIndex), withRowAnimation: .Automatic)
            case .Delete:
                tableView.deleteSections(NSIndexSet(index: sectionIndex), withRowAnimation: .Automatic)
            case .Update:
                tableView.deleteSections(NSIndexSet(index: sectionIndex), withRowAnimation: .Automatic)
            default: break
            }
        }

        override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
            if segue.identifier == "editReminder" {

               // let task = segue.destinationViewController as! UINavigationController

                let navController = segue.destinationViewController as! UINavigationController
                let task = navController.topViewController as! Reminder

                if let indexPath = tableView.indexPathForCell(sender as! ReminderListCell) {
                    task.reminders = reminders[indexPath.row]
                }


            }
        }


        func controller(controller: NSFetchedResultsController, didChangeObject anObject: AnyObject, atIndexPath indexPath: NSIndexPath?, forChangeType type: NSFetchedResultsChangeType, newIndexPath: NSIndexPath?) {

            switch type {
            case .Insert:
                if let _newIndexPath = newIndexPath {
                    tableView.insertRowsAtIndexPaths([_newIndexPath], withRowAnimation: .Fade)
                }
            case .Delete:
                if let _indexPath = indexPath {
                    tableView.deleteRowsAtIndexPaths([_indexPath], withRowAnimation: .Left)
                }
            case .Update:
                if let _indexPath = indexPath {
                    tableView.reloadRowsAtIndexPaths([_indexPath], withRowAnimation: .Fade)
                }

            default:
                tableView.reloadData()
            }

            reminders = controller.fetchedObjects as! [ReminderData]
        }

        func controllerDidChangeContent(controller: NSFetchedResultsController) {
            tableView.endUpdates()
        }


        @IBAction func selectCategory(sender: UISegmentedControl) {

            let selectedValue = sender.titleForSegmentAtIndex(sender.selectedSegmentIndex)


            switch selectedValue!{

            case "Task":
               loadData(selectedValue!)
                break
            case "Medication":
                loadData(selectedValue!)
                break
            case "Appointment":
                loadData(selectedValue!)
                break
            default:
                loadData(selectedValue!)
                break

            }
        }


        override func scrollViewDidEndDecelerating(scrollView: UIScrollView) {

            var fixedFrame:CGRect = self.menuViewRelative.frame
            fixedFrame.origin.y = 0 + scrollView.contentOffset.y
            self.menuViewRelative.frame = fixedFrame
        }

    }

ReminderData.swift

class ReminderData : NSManagedObject {

    @NSManaged var date: NSDate?
    @NSManaged var name: String?
    @NSManaged var category: String?
    @NSManaged var time : NSDate?

    func stringForDate() -> String {

        let dateFormatter = NSDateFormatter()
        dateFormatter.dateStyle = NSDateFormatterStyle.MediumStyle
        if let date = date {
            return dateFormatter.stringFromDate(date)
        } else {
            return ""
        }


    }

    func stringForTime() -> String {

        let dateFormatter = NSDateFormatter()
        dateFormatter.dateFormat = "hh:mm a"
        if let time = time {
            return dateFormatter.stringFromDate(time)
        } else {
            return ""
        }


    }


}

Answer 1

替换

task.stringForDate()
task.stringForTime() 

与

reminders[indexPath.row].stringForDate()
reminders[indexPath.row].stringForTime()