在Swift CoreData中添加用日期分隔的部分到UITableView

Question

有人可以告訴我如何使用CoreData添加包含日期的部分？

當我們寫入一些數據時，我有從CoreDate和AddTableViewController存儲所有數據的detailViewController。

詳細視圖控制器

import UIKit 

import CoreData 

class DetailViewController: UIViewController, UITableViewDataSource, UITableViewDelegate, NSFetchedResultsControllerDelegate, AddTableViewControllerDelegate { 

@IBOutlet weak var tableView: UITableView! 

var detailTaskModel: Items! 
var costsValues:Int! 


@IBOutlet weak var sumLabel: UILabel! 

// CoreData 
let managedObjectContext = (UIApplication.sharedApplication().delegate as AppDelegate).managedObjectContext 
var fetchedResultsController: NSFetchedResultsController = NSFetchedResultsController() 



override func viewDidLoad() { 
    super.viewDidLoad() 

    self.tableView.delegate = self 
    self.tableView.dataSource = self 

    fetchedResultsController = getFetchedResultsController() 
    fetchedResultsController.delegate = self 
    fetchedResultsController.performFetch(nil) 

    costsValues = getAccountCountSum() 
    self.tableView.reloadData() 

} 

override func didReceiveMemoryWarning() { 
    super.didReceiveMemoryWarning() 
    // Dispose of any resources that can be recreated. 
} 


// UITableViewDataSource 
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int { 
    return fetchedResultsController.sections![section].numberOfObjects 
} 

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell { 
    var cell: DetailTableViewCell = tableView.dequeueReusableCellWithIdentifier("detailCell") as DetailTableViewCell 
    let thisCost = fetchedResultsController.objectAtIndexPath(indexPath) as Costs 

    cell.nazwaWydatkuLabel.text = thisCost.costsName 
    cell.wartośćLabel.text = "\(thisCost.costsValue) zł" 

    return cell 
} 

@IBAction func addCostButtonPressed(sender: UIBarButtonItem) { 

    self.performSegueWithIdentifier("addCostVC", sender: self) 
} 

func numberOfSectionsInTableView(tableView: UITableView) -> Int { 
    return fetchedResultsController.sections!.count 
} 

override func viewDidAppear(animated: Bool) { 
    costsValues = getAccountCountSum() 
    refreshTable() 
    self.tableView.reloadData() 
} 

// CoreData Functions 
func taskFetchRequest() -> NSFetchRequest { 
    let fetchRequest = NSFetchRequest(entityName: "Costs") 
    let sortDescriptor = NSSortDescriptor(key: "costsDate", ascending: true) 
    fetchRequest.sortDescriptors = [sortDescriptor] 
    return fetchRequest 
} 

func getFetchedResultsController() -> NSFetchedResultsController { 
    fetchedResultsController = NSFetchedResultsController(fetchRequest: taskFetchRequest(), managedObjectContext: managedObjectContext!, sectionNameKeyPath: nil, cacheName: nil) 
    return fetchedResultsController 
} 

// NSFetchedResultsControllerDelegate 
func controllerDidChangeContent(controller: NSFetchedResultsController) { 
    tableView.reloadData() 
} 

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

    let thisCost = fetchedResultsController.objectAtIndexPath(indexPath) as Costs 
    managedObjectContext?.deleteObject(thisCost) 
    costsValues = getAccountCountSum() 

    refreshTable() 
    self.tableView.reloadData() 
    (UIApplication.sharedApplication().delegate as AppDelegate).saveContext() 
} 

// Sum count in all accouts 
func getAccountCountSum() -> Int { 
    let appDelegate = UIApplication.sharedApplication().delegate as AppDelegate 
    let managedContext : NSManagedObjectContext = appDelegate.managedObjectContext! 
    var fetchRequest = NSFetchRequest(entityName: "Costs") 
    fetchRequest.returnsObjectsAsFaults = false 
    var results: NSArray = managedContext.executeFetchRequest(fetchRequest, error: nil)! 

    var accountsSum: Int = 0 
    for res in results { 
     var accountCount = res.valueForKey("costsValue") as Int 
     accountsSum += accountCount 
    } 
    self.sumLabel.text = String("\(costsValues) zł") 
    return accountsSum 
} 

func refreshTable() { 
    getAccountCountSum() 
    self.tableView.reloadData() 
} 

}

AddTableViewController

@IBAction func saveButtonTapped(sender: UIBarButtonItem) { 

    // CoreData Access 
    let appDelegate = (UIApplication.sharedApplication().delegate as AppDelegate) 
    var managedObjectContext = appDelegate.managedObjectContext 
    let entityDescription = NSEntityDescription.entityForName("Costs", inManagedObjectContext: managedObjectContext!) 

    let cost = Costs(entity: entityDescription!, insertIntoManagedObjectContext: managedObjectContext!) 

    cost.costsName = cellThreeNoteTextField.text 
    cost.costsValue = (cellOnePriceTextField.text).toInt()! 
    cost.costsDate = datePicker.date 

    // Saving data 
    appDelegate.saveContext() 

    var request = NSFetchRequest(entityName: "Costs") 
    var error:NSError? = nil 

    var results:NSArray = managedObjectContext!.executeFetchRequest(request, error: &error)! 

    for res in results { 
     println(res) 

    } 
    delegate?.refreshTable() 
    self.navigationController?.popViewControllerAnimated(true) 

} 

Answer 1

由於您使用的是NSFetchedResultsController，您只要在管理對象傳遞一個關鍵sectionNameKeyPath參數創建節。抓取的結果控制器的sections屬性將根據抓取對象中該關鍵路徑的值將結果分解爲多個部分。

您還需要執行UITableView回調才能使用這些部分 - 例如，sectionIndexTitlesForTableView和tableView:titleForHeaderInSection:。這些在NSFetchedResultsController文檔中有描述。