didselectatrow更新下面的多個單元格重新加載tableview +計數器

Question

這是一個兩部分的問題，其中第一個是經過長達一個星期的嘗試來弄清楚這一點，我仍然留下一個空白。我終於讓單個單元格顯示與文本字段中的選擇相關的適當數字，但仍未找出爲什麼要重新加載到tableview中的單元格也顯示更新的文本字段。基本上我只想讓cardCounter的文本字段只在選中的行中更新，然後如果用戶滾動回到原來的位置，如果他們決定刪除它，它會向他們顯示有多少對象可用的計數器。

第二個問題是我試圖爲總數限制爲30的cardCount製作一個計數器，並且對於每個選定的cardCount對象，其中的1個被縮小到29,28,27等等。在我的第一個項目上完成一些小的代碼。

import UIKit 
import CoreData 

class CardSelectionViewController: UIViewController, UITableViewDelegate, UIAlertViewDelegate, UISearchBarDelegate, NSFetchedResultsControllerDelegate { 

var passedDeckObject: Deck? 
let managedObjectContext = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext 

var deckCardCount = 30 

@IBOutlet weak var cardsListed: UITableView! 

@IBOutlet weak var cardSearch: UISearchBar! 


@IBAction func backButton(sender: AnyObject) { 
} 

@IBAction func saveCardSelection(sender: AnyObject) { 

    if deckCardCount != 30 { 

    let selectmorecards = UIAlertController(title: "Select More Cards", message: "Please Select More Cards To Complete Deck", preferredStyle: .Alert) 
    let okCardAction: UIAlertAction = UIAlertAction(title: "OK", style: .Cancel, handler: nil) 
     selectmorecards.addAction(okCardAction) 
     self.presentViewController(selectmorecards, animated: true, completion: nil) 

    } else { 

    if deckCardCount == 30 { 
    let alertController = UIAlertController(title: "All Cards Correct?", message: "Are all the cards in the deck what you wanted?", preferredStyle: .Alert) 
    let cancelAction: UIAlertAction = UIAlertAction(title: "Cancel", style: .Cancel, handler: nil) 
    let okAction: UIAlertAction = UIAlertAction(title: "OK", style: .Default) { (action) -> Void in 
     self.managedObjectContext?.save(nil) 

     self.presentViewController(alertController, animated: true, completion: nil) 

     } 
     } 
    } 
} 

var costfrc: NSFetchedResultsController! 
var frc: NSFetchedResultsController = NSFetchedResultsController() 
func getFetchedResultsController() -> NSFetchedResultsController { 
    frc = NSFetchedResultsController(fetchRequest: listFetchRequest(), managedObjectContext: managedObjectContext!, sectionNameKeyPath: nil, cacheName: nil) 

    return frc 

} 
func listFetchRequest() -> NSFetchRequest { 

    let requiredClassName = passedDeckObject!.classSelected.classname 
    var requiredCardClasses = [Int]() 
    let fetchRequest = NSFetchRequest(entityName: "Cards") 
    let sortDescriptor = NSSortDescriptor(key: "name", ascending: true) 
    switch(requiredClassName) { 
     case "Warrior": 
     requiredCardClasses = [1,10] 
     case "Shaman": 
     requiredCardClasses = [2,10] 
     case "Rogue": 
     requiredCardClasses = [3,10] 
     case "Paladin": 
     requiredCardClasses = [4,10] 
     case "Hunter": 
     requiredCardClasses = [5,10] 
     case "Druid": 
     requiredCardClasses = [6,10] 
     case "Warlock": 
     requiredCardClasses = [7,10] 
     case "Mage": 
     requiredCardClasses = [8,10] 
     case "Priest": 
     requiredCardClasses = [9,10] 
     default: 
     requiredCardClasses = [10] 
    } 
    fetchRequest.sortDescriptors = [sortDescriptor] 
    fetchRequest.predicate = NSPredicate(format:"cardClass IN %@", requiredCardClasses) 

    return fetchRequest 
} 

func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int { 
    let numberofRowsInSection = frc.sections?[section].numberOfObjects 
    return numberofRowsInSection! 
} 


//Mark cell displayed with colored text// 
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell { 

    var cell: firstCardDetails = cardsListed.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! firstCardDetails 
    let listed = frc.objectAtIndexPath(indexPath) as! Cards 
    var cardCount = 0 
    var myDeckCards: DeckCards? 
    for eachDeckCard in listed.cardselections { 
     let myDeckCard = eachDeckCard as! DeckCards 
     if myDeckCard.cardsstored == passedDeckObject { 
      myDeckCards = eachDeckCard as? DeckCards 
      cardCount = myDeckCards!.numberSelected.integerValue 
     } 
    } 




    cell.cardName?.text = listed.name as String 
    if listed.cardType.isEqualToValue(1) { 
     cell.cardAttack?.text = "*" 
    } else { 
     if listed.cardType.isEqualToValue(2) { 
      cell.cardAttack?.text = "*" 
     } else { 
    cell.cardAttack?.text = listed.attack.stringValue 
    } 
    } 
    if listed.cardType.isEqualToNumber(1) { 
     cell.cardHealth?.text = "*" 
    } else { 
     if listed.cardType.isEqualToValue(2) { 
      cell.cardHealth?.text = "*" 
     } else { 
    cell.cardHealth?.text = listed.health.stringValue 
    } 
    } 
    cell.cardCost?.text = listed.cost.stringValue 

     if listed.cardType.isEqualToNumber(0) { 
      cell.cardType?.text = "Minion" 
     } else { 
      if listed.cardType.isEqualToNumber(1) { 
       cell.cardType?.text = "Spell" 
      } else { 
       if listed.cardType.isEqualToNumber(2) { 
       cell.cardType?.text = "Weapon" 
      } 
      } 
    } 
    if listed.rarity.isEqualToNumber(1) { 
     cell.rarityType?.text = "Legendary" 
     cell.rarityType?.textColor = UIColor.orangeColor() 
    } else { 
     if listed.rarity.isEqualToNumber(2) { 
      cell.rarityType?.text = "Epic" 
      cell.rarityType?.textColor = UIColor.purpleColor() 
     } else { 
      if listed.rarity.isEqualToNumber(3) { 
       cell.rarityType?.text = "Rare" 
       cell.rarityType?.textColor = UIColor.blueColor() 
      } else { 
       if listed.rarity.isEqualToNumber(4) { 
        cell.rarityType?.text = "Common" 
        cell.rarityType?.textColor = UIColor.grayColor() 
       } else { 
        if listed.rarity.isEqualToNumber(5) { 
         cell.rarityType?.text = "Starter" 
         cell.rarityType?.textColor = UIColor.blackColor() 
        } 
       } 
      } 
     } 
    } 
    if listed.cardClass.isEqualToNumber(1) { 
     cell.cardName?.textColor = UIColor(red: 0xbe/255, green: 0x23/255, blue: 0x0f/255, alpha: 1.0) 
    } else { 
     if listed.cardClass.isEqualToNumber(2) { 
      cell.cardName?.textColor = UIColor.blueColor() 
     } else { 
      if listed.cardClass.isEqualToNumber(3) { 
       cell.cardName?.textColor = UIColor(red: 0xE2/255, green: 0xA8/255, blue: 0x79/255, alpha: 1.0) 
      } else { 
       if listed.cardClass.isEqualToNumber(4) { 
        cell.cardName?.textColor = UIColor(red: 0xFF/255, green: 0xAA/255, blue: 0x00/255, alpha: 1.0) 
       } else { 
        if listed.cardClass.isEqualToNumber(5) { 
         cell.cardName?.textColor = UIColor(red: 0x22/255, green: 0x63/255, blue: 0x29/255, alpha: 1.0) 
        } else { 
         if listed.cardClass.isEqualToNumber(6) { 
          cell.cardName?.textColor = UIColor.brownColor() 
         } else { 
          if listed.cardClass.isEqualToNumber(7) { 
           cell.cardName?.textColor = UIColor(red: 0xBB/255, green: 0x76/255, blue: 0xE4/255, alpha: 1.0) 
          } else { 
           if listed.cardClass.isEqualToNumber(8) { 
            cell.cardName?.textColor = UIColor(red: 0x9E/255, green: 0xB5/255, blue: 0xFF/255, alpha: 1.0) 
           } else { 
            if listed.cardClass.isEqualToNumber(9) { 
             cell.cardName?.textColor = UIColor.grayColor() 
            } else { 
             if listed.cardClass.isEqualToNumber(10) { 
              cell.cardName?.textColor = UIColor.blackColor() 
             } 
             } 
           } 
          } 

          } 
         } 
        } 
       } 
     } 
    } 
    return cell 
} 
//reload content// 
func controllerDidChangeContent(controller: NSFetchedResultsController) { 
    cardsListed.reloadData() 
} 


//selected row functions// 
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) { 
    var cardCount = 0 
    var myDeckCards: DeckCards? 
    let listed = frc.objectAtIndexPath(indexPath) as! Cards 


    var cell = cardsListed.cellForRowAtIndexPath(indexPath) as! firstCardDetails 

    cell.indexOfAccessibilityElement(listed) 

    // check: is there already a DeckCards object for this Card and this Deck? 
    let deckCardsSet = listed.cardselections 
    println("The set of DeckCards for that Card is \(deckCardsSet.count)") 
    for eachDeckCard in listed.cardselections { 
     let myDeckCard = eachDeckCard as! DeckCards 
     if myDeckCard.cardsstored == passedDeckObject { 
      // There is already a DeckCard object for this Card and currentDeck 
      myDeckCards = eachDeckCard as? DeckCards 
     } 
    } 
    if myDeckCards == nil { 
     // There is no DeckCard object for this Card and currentDeck 
     // So create one... 
     myDeckCards = NSEntityDescription.insertNewObjectForEntityForName("DeckCards", inManagedObjectContext: managedObjectContext!) as? DeckCards 
     myDeckCards!.cardsselected = listed 
     myDeckCards!.cardsstored = passedDeckObject! 
    } 
    // your code to determine numberSelected here; I'll assume 2! 
    cardCount = myDeckCards!.numberSelected.integerValue 
    deckCardCount = myDeckCards!.deckcardCount.integerValue 


    cardCount = cardCount == 2 ? 0 : cardCount + 1 
    myDeckCards!.numberSelected = cardCount 
    deckCardCount = deckCardCount - cardCount 
    cell.cardCounter.text = " " + cardCount.description 
     if deckCardCount == 30 { 
      if cell.selected { 
       deckCardCount = deckCardCount + 1 
      } 
     myDeckCards!.numberSelected = deckCardCount 
     myDeckCards!.numberSelected = cardCount 
     } 
    println(deckCardCount) 
    println(cardCount) 

} 

//searchBar contoller// 
func searchBar(searchBar: UISearchBar, textDidChange searchText: String) { 

    searchBar.setShowsCancelButton(true, animated: true) 
    let requiredClassName = passedDeckObject!.classSelected.classname 
    var requiredCardClasses = [Int]() 
    switch(requiredClassName) { 
    case "Warrior": 
     requiredCardClasses = [1,10] 
    case "Shaman": 
     requiredCardClasses = [2,10] 
    case "Rogue": 
     requiredCardClasses = [3,10] 
    case "Paladin": 
     requiredCardClasses = [4,10] 
    case "Hunter": 
     requiredCardClasses = [5,10] 
    case "Druid": 
     requiredCardClasses = [6,10] 
    case "Warlock": 
     requiredCardClasses = [7,10] 
    case "Mage": 
     requiredCardClasses = [8,10] 
    case "Priest": 
     requiredCardClasses = [9,10] 
    default: 
     requiredCardClasses = [10] 
    } 
    if !searchText.isEmpty { 
     // Clear out the fetchedResultController 
     frc = getFetchedResultsController() 
     // Setup the fetch request 
     let fetchRequest = NSFetchRequest(entityName: "Cards") 
     fetchRequest.fetchLimit = 565 
     fetchRequest.predicate = NSCompoundPredicate(type: .AndPredicateType, subpredicates: [NSPredicate(format: "name contains[cd] %@", searchText), NSPredicate(format: "cardClass IN %@", requiredCardClasses)]) 
     let sortDescriptor = NSSortDescriptor(key: "name", ascending: true) 
     fetchRequest.sortDescriptors = [sortDescriptor] 
     println(fetchRequest.predicate) 
     //end// 
     //cost fetch request begins here// 
     let costfetchRequest = NSFetchRequest(entityName: "cardCost") 
     costfetchRequest.fetchLimit = 565 
     costfetchRequest.predicate = NSPredicate(format: "cardCost = %i", searchText) 
     let costSortDescriptor = NSSortDescriptor(key: "cardCost", ascending: true) 
     costfetchRequest.sortDescriptors = [sortDescriptor] 
     //end// 

     // Pass the fetchRequest and the context as parameters to the fetchedResultController 
     frc = NSFetchedResultsController(fetchRequest: fetchRequest, managedObjectContext:managedObjectContext!, 
      sectionNameKeyPath: nil, cacheName: nil) 
     // Make the fetchedResultController a delegate of the MoviesViewController class 
     frc.delegate = self 
     // Execute the fetch request or display an error message in the Debugger console 
     var error: NSError? = nil 
     if (!frc.performFetch(&error)) { 
      println("Error: \(error?.localizedDescription)") 
     } 
     // Refresh the table view to show search results 
     cardsListed.reloadData() 
    } 
} 
//search Cancel 
func searchBarCancelButtonClicked(searchBar: UISearchBar) { 
    searchBar.text = nil 
    searchBar.showsCancelButton = false // Hide the cancel 
    searchBar.resignFirstResponder() // Hide the keyboard 

    // Refresh the table view to show fetchedResultController results 
    cardsListed.reloadData() 
} 
override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) { 

    self.view.endEditing(true) 
} 
func textFieldShouldReturn(textField: UITextField) -> Bool { 

    textField.resignFirstResponder() 
    return true 
} 

override func viewDidLoad() { 
    super.viewDidLoad() 

    println(passedDeckObject?.deckname) 
    var nib = UINib(nibName: "firstCardDetails", bundle: nil) 
    cardsListed.registerNib(nib, forCellReuseIdentifier: "cell") 
    frc = getFetchedResultsController() 
    frc.delegate = self 
    frc.performFetch(nil) 


} 

override func didReceiveMemoryWarning() { 
    super.didReceiveMemoryWarning() 
} 

Answer 1

對於問題＃1 ....

它通常是一個壞主意，當你使用可重複使用的細胞製造的cellForRowAtIndexPath（或prepareForReuse）以外的細胞變化。有一些例外，但大多數情況下，這是安全的選擇。最好的策略是在其他方法中更改只有，然後重新加載受影響的單元（或全部）。

由於單元格已被緩存，因此每當使用單元格時，您對單元格所做的更改都會顯示在屏幕上，除非您在返回單元格時顯式覆蓋更改。

在didSelectRowAtIndexPath方法中，您應該計算所需並將其存儲在某個位置，然後在cellForRowAtIndexPath中更新其顯示。