将核心数据从选定的表单元传递到新的视图控制器 [英] Pass core data from selected table cell to new view controller

问题描述

我尝试将选定表格单元格中的数据（标题，成分，步骤，图像）传递到新的视图控制器。但我不知道该怎么做。我有很多错误，所以现在我再次开始。谁能帮助我？我刚接触编码。感谢:-)我的代码：

$ b

  VIEWCONTROLLER.SWIFT   class ViewController：UIViewController，UITableViewDataSource，UITableViewDelegate {
 
 @IBOutlet weak var tableView：UITableView！ 
 var recipes = [Recipe]（）
 
 override func viewDidLoad（）{
 super.viewDidLoad（）
 tableView.delegate = self 
 tableView。 dataSource = self 
} 
 
 override func viewDidAppear（animated：Bool）{
 fetchAndSetResults（）
 tableView.reloadData（）
} 
 
 func fetchAndSetResults（）{
 let app = UIApplication.sharedApplication（）。delegate as！ AppDelegate 
 let context = app.managedObjectContext 
 let fetchRequest = NSFetchRequest（entityName：Recipe）
 
 do {
 let results = try context.executeFetchRequest（fetchRequest） 
 self.recipes = results as！ [配方] 
} catch let err as NSError {
 print（err.debugDescription）
} 
} 
 
 func tableView（tableView：UITableView，cellForRowAtIndexPath indexPath：NSIndexPath） - > UITableViewCell {
如果let cell = tableView.dequeueReusableCellWithIdentifier（RecipeCell）as？ RecipeCell {
 let recipe = recipes [indexPath.row] 
 cell.configureCell（recipe）
 return cell 
} else {
 return RecipeCell } 
} 
 
 func numberOfSectionsInTableView（tableView：UITableView） - > int {
 return 1 
} 
 
 func tableView（tableView：UITableView，numberOfRowsInSection section：Int） - > int {
 return recipes.count 
} 
 
 func tableView（tableView：UITableView，didSelectRowAtIndexPath indexPath：NSIndexPath）{
 self.tableView.deselectRowAtIndexPath（indexPath，animated： true）
} 
 
 override func prepareForSegue（segue：UIStoryboardSegue，sender：AnyObject？）{
 if（segue.identifier ==RecipeDetail）{
 / /我想将数据从表单单元传递到新的视图控制器（RECIPEDETAILVC）
} 
} 
 
 func tableView（tableView：UITableView，canEditRowAtIndexPath indexPath：NSIndexPath） > Bool {
 return true 
} 
 
 func tableView（tableView：UITableView，commitEditingStyle editingStyle：UITableViewCellEditingStyle，forRowAtIndexPath indexPath：NSIndexPath）{
 if（editingStyle == UITableViewCellEditingStyle。删除）{
 
 let app = UIApplication.sharedApplication（）。delegate as！ AppDelegate 
 let context = app.managedObjectContext 
 
 context.deleteObject（recipes [indexPath.row]）
 app.saveContext（）
 
 recipes.removeAtIndex （indexPath.row）
 tableView.reloadData（）
} 
} 
} 
  

CREATERECIPE.SWIFT

  class CreateRecipeVC：UIViewController，UIImagePickerControllerDelegate，UINavigationControllerDelegate {
 
 @IBOutlet weak var recipeTitle：UITextField！ 
 @IBOutlet weak var recipeIngredients：UITextField！ 
 @IBOutlet weak var recipeSteps：UITextField！ 
 @IBOutlet weak var recipeImage：UIImageView！ 
 @IBOutlet weak var addRecipeBtn：UIButton！ 
 
 var imagePicker：UIImagePickerController！ 
 
 override func viewDidLoad（）{
 super.viewDidLoad（）
 imagePicker = UIImagePickerController（）
 imagePicker.delegate = self 
 recipeImage.layer.cornerRadius = 5.0 
 recipeImage.clipsToBounds = true 
 
} 
 
 func imagePickerController（picker：UIImagePickerController，didFinishPickingImage image：UIImage，editingInfo：[String：AnyObject]？） 
 
 imagePicker.dismissViewControllerAnimated（true，completion：nil）
 recipeImage.image = image 
 
} 
 
 @IBAction func addImage ：AnyObject！）{
 presentViewController（imagePicker，animated：true，completion：nil）
} 
 
 @IBAction func createRecipe（sender：AnyObject！）{
 if let title = recipeTitle.text where title！={
 let app = UIApplication.sharedApplication（）。delegate as！ AppDelegate 
 let context = app.managedObjectContext 
 let entity = NSEntityDescription.entityForName（Recipe，inManagedObjectContext：context）！ 
 let recipe = Recipe（entity：entity，insertIntoManagedObjectContext：context）
 recipe.title = title 
 recipe.ingredients = recipeIngredients.text 
 recipe.steps = recipeSteps.text 
 recipe.setRecipeImage（recipeImage.image！）
 
 context.insertObject（recipe）
 
 do {
 try context.save（）
} catch {
 print（Could not save recipe）
} 
 
 self.navigationController？.popViewControllerAnimated（true）
} 
} 
 
} 
  

RECIPEDETAILVC.SWIFT

  import UIKit 
 import CoreData 
 
 class RecipeDetailVC：UIViewController {
 
 @IBOutlet弱var recipeImage：UIImageView！ 
 @IBOutlet weak var recipeTitle：UILabel！ 
 @IBOutlet weak var recipeIngredients：UILabel！ 
 @IBOutlet weak var recipeSteps：UILabel！ 
 
 override func viewDidLoad（）{
 super.viewDidLoad（）
 
 //我想显示我选择的表格单元中的内核数据信息。 
} 
} 
  

RECIPECELL.SWIFT / p>

  class RecipeCell：UITableViewCell {
 
 @IBOutlet weak var recipeTitle：UILabel！ 
 @IBOutlet weak var recipeImage：UIImageView！ 
 
 func configureCell（recipe：Recipe）{
 recipeTitle.text = recipe.title 
 recipeImage.image = recipe.getRecipeImage（）
} 
 
} 
  

解决方案

  var mySelection：Int？ 
 func tableView（tableView：UITableView，didSelectRowAtIndexPath indexPath：NSIndexPath）{
 self.tableView.deselectRowAtIndexPath（indexPath，animated：true）
 mySelection = indexPath.row 
} 
 
 
 
 
然后，在执行segue时使用。
  override func prepareForSegue（segue：UIStoryboardSegue，sender：AnyObject？）{
 if（segue.identifier ==RecipeDetail）{
 //我想通过数据从表单单元到新的视图控制器（RECIPEDETAILVC）
让recipeDetailControler = segue.destinationViewController as！ RecipeDetailViewController 
 
如果let mySelection = mySelection {
 let recipe = recipes [mySelection] 
 //将此函数添加到
 recipeDetailControler.configureRecipeData（recipe）
} 
} 
} 
  
将此函数添加到RecipeDetailViewController：
  func configureRecipeData（recipe：Recipe）{
 
 //实现ME 
 
} 
  
 
I'm trying to pass data (title, ingredients, steps, image) from the selected table cell to a new view controller. But I don't know how to do that. I got lots of errors, so now I'm starting again. Can anyone help me? I'm new to coding. Thanks:-) My code: 

VIEWCONTROLLER.SWIFT
class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {

    @IBOutlet weak var tableView: UITableView!
    var recipes = [Recipe]()

    override func viewDidLoad() {
        super.viewDidLoad()
        tableView.delegate = self
        tableView.dataSource = self
    }

    override func viewDidAppear(animated: Bool) {
        fetchAndSetResults()
        tableView.reloadData()
    }

    func fetchAndSetResults(){
        let app = UIApplication.sharedApplication().delegate as! AppDelegate
        let context = app.managedObjectContext
        let fetchRequest = NSFetchRequest(entityName: "Recipe")

        do {
            let results = try context.executeFetchRequest(fetchRequest)
            self.recipes = results as! [Recipe]
        } catch let err as NSError {
            print(err.debugDescription)
        }
    }

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        if let cell = tableView.dequeueReusableCellWithIdentifier("RecipeCell") as? RecipeCell {
            let recipe = recipes[indexPath.row]
            cell.configureCell(recipe)
            return cell
        } else {
            return RecipeCell()
        }
    }

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

    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return recipes.count
    }

    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
        self.tableView.deselectRowAtIndexPath(indexPath, animated: true)
    }

    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if (segue.identifier == "RecipeDetail") {
            //I WANT TO PASS THE DATA FROM THE TABLE CELL TO THE NEW VIEW CONTROLLER (RECIPEDETAILVC)
        }
    }

    func tableView(tableView: UITableView, canEditRowAtIndexPath indexPath: NSIndexPath) -> Bool {
        return true
    }

    func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
        if (editingStyle == UITableViewCellEditingStyle.Delete) {

            let app = UIApplication.sharedApplication().delegate as! AppDelegate
            let context = app.managedObjectContext

            context.deleteObject(recipes[indexPath.row])
            app.saveContext()

            recipes.removeAtIndex(indexPath.row)
            tableView.reloadData()
        }
    }
}
CREATERECIPE.SWIFT
class CreateRecipeVC: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate {

    @IBOutlet weak var recipeTitle: UITextField!
    @IBOutlet weak var recipeIngredients: UITextField!
    @IBOutlet weak var recipeSteps: UITextField!
    @IBOutlet weak var recipeImage: UIImageView!
    @IBOutlet weak var addRecipeBtn: UIButton!

    var imagePicker: UIImagePickerController!

    override func viewDidLoad() {
        super.viewDidLoad()
        imagePicker = UIImagePickerController()
        imagePicker.delegate = self
        recipeImage.layer.cornerRadius = 5.0
        recipeImage.clipsToBounds = true

    }

    func imagePickerController(picker: UIImagePickerController, didFinishPickingImage image: UIImage, editingInfo: [String : AnyObject]?) {

        imagePicker.dismissViewControllerAnimated(true, completion: nil)
        recipeImage.image = image

    }

    @IBAction func addImage(sender: AnyObject!) {
        presentViewController(imagePicker, animated: true, completion: nil)
    }

    @IBAction func createRecipe(sender: AnyObject!) {
        if let title = recipeTitle.text where title != "" {
            let app = UIApplication.sharedApplication().delegate as! AppDelegate
            let context = app.managedObjectContext
            let entity = NSEntityDescription.entityForName("Recipe", inManagedObjectContext: context)!
            let recipe = Recipe(entity: entity, insertIntoManagedObjectContext: context)
            recipe.title = title
            recipe.ingredients = recipeIngredients.text
            recipe.steps = recipeSteps.text
            recipe.setRecipeImage(recipeImage.image!)

            context.insertObject(recipe)

            do {
                try context.save()
            } catch {
                print("Could not save recipe")
            }

            self.navigationController?.popViewControllerAnimated(true)
        }
    }

}
RECIPEDETAILVC.SWIFT
import UIKit
import CoreData

class RecipeDetailVC: UIViewController {

    @IBOutlet weak var recipeImage: UIImageView!
    @IBOutlet weak var recipeTitle: UILabel!
    @IBOutlet weak var recipeIngredients: UILabel!
    @IBOutlet weak var recipeSteps: UILabel!

    override func viewDidLoad() {
        super.viewDidLoad()

        //I WANT TO DISPLAY THE CORE DATA INFORMATION FROM THE TABLE CELL I SELECTED.
    }
}
RECIPECELL.SWIFT
class RecipeCell: UITableViewCell {

    @IBOutlet weak var recipeTitle: UILabel!
    @IBOutlet weak var recipeImage: UIImageView!

    func configureCell(recipe: Recipe) {
        recipeTitle.text = recipe.title
        recipeImage.image = recipe.getRecipeImage()
    }

}

解决方案
You need to track which item the person clicked.
var mySelection: Int?
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
    self.tableView.deselectRowAtIndexPath(indexPath, animated: true)
    mySelection = indexPath.row
}
Then, use that when doing the segue.
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?)     {
    if (segue.identifier == "RecipeDetail") {
        //I WANT TO PASS THE DATA FROM THE TABLE CELL TO THE NEW VIEW CONTROLLER (RECIPEDETAILVC)
        let recipeDetailControler = segue.destinationViewController as! RecipeDetailViewController

        if let mySelection = mySelection {
            let recipe = recipes[mySelection]
            // add this function to your
            recipeDetailControler.configureRecipeData(recipe)
        }
    }
}
Add this function to RecipeDetailViewController:
func configureRecipeData(recipe: Recipe) {

    // IMPLEMENT ME

}


                        
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