Implements Edit and Delete behavior

iOSTemplate/Base.lproj/Main.storyboard

@@ -47,6 +47,7 @@
                                     <outlet property="nameLabel" destination="CD1-k0-BhS" id="a3s-8U-PBl"/>
                                     <outlet property="photoImageView" destination="Ahk-x7-gIe" id="Ywa-p6-yE8"/>
                                     <outlet property="ratingControl" destination="mW4-wS-nxh" id="c6i-Bz-Y3a"/>
+                                    <segue destination="BYZ-38-t0r" kind="show" identifier="ShowDetail" id="tWp-7C-aV5"/>
                                 </connections>
                             </tableViewCell>
                         </prototypes>
@@ -174,10 +175,13 @@
                 </navigationController>
                 <placeholder placeholderIdentifier="IBFirstResponder" id="GiG-92-fkl" userLabel="First Responder" sceneMemberID="firstResponder"/>
             </objects>
-            <point key="canvasLocation" x="860" y="133.5832083958021"/>
+            <point key="canvasLocation" x="926" y="484"/>
         </scene>
     </scenes>
     <resources>
         <image name="defaultPhoto" width="1080" height="1080"/>
     </resources>
+    <inferredMetricsTieBreakers>
+        <segue reference="tWp-7C-aV5"/>
+    </inferredMetricsTieBreakers>
 </document>

iOSTemplate/MealTableViewController.swift

@@ -6,6 +6,7 @@
 //
 
 import UIKit
+import os.log
 
 class MealTableViewController: UITableViewController {
     // MARK: Properties
@@ -14,6 +15,9 @@ class MealTableViewController: UITableViewController {
 
     override func viewDidLoad() {
         super.viewDidLoad()
+        
+        // Use the edit button item provided by the table view controller.
+        navigationItem.leftBarButtonItem = editButtonItem
 
         // Load the sample data.
         loadSampleMeals()
@@ -46,25 +50,22 @@ class MealTableViewController: UITableViewController {
         return cell
     }
 
-    /*
     // Override to support conditional editing of the table view.
     override func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
         // Return false if you do not want the specified item to be editable.
         return true
     }
-    */
 
-    /*
     // Override to support editing the table view.
-    override func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {
+    override func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {
         if editingStyle == .delete {
             // Delete the row from the data source
+            meals.remove(at: indexPath.row)
             tableView.deleteRows(at: [indexPath], with: .fade)
         } else if editingStyle == .insert {
             // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
         }    
     }
-    */
 
     /*
     // Override to support rearranging the table view.
@@ -81,25 +82,54 @@ class MealTableViewController: UITableViewController {
     }
     */
 
-    /*
     // MARK: - Navigation
 
     // In a storyboard-based application, you will often want to do a little preparation before navigation
     override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
-        // Get the new view controller using segue.destination.
-        // Pass the selected object to the new view controller.
+        super.prepare(for: segue, sender: sender)
+        
+        switch(segue.identifier ?? "") {
+            
+        case "AddItem":
+            os_log("Adding a new meal.", log: OSLog.default, type: .debug)
+        
+        case "ShowDetail":
+            guard let mealDetailViewController = segue.destination as? MealViewController else {
+                fatalError("Unexpected destination: \(segue.destination)")
+            }
+            
+            guard let selectedMealCell = sender as? MealTableViewCell else {
+                fatalError("Unexpected sender: \(String(describing: sender))")
+            }
+            
+            guard let indexPath = tableView.indexPath(for: selectedMealCell) else {
+                fatalError("The selected cell is not being displayed by the table")
+            }
+            
+            let selectedMeal = meals[indexPath.row]
+            mealDetailViewController.meal = selectedMeal
+        
+        default:
+            fatalError("Unexpected Segue Identifier; \(String(describing: segue.identifier))")
+        }
     }
-    */
     
     // MARK: Actions
     
     @IBAction func unwindToMealList(sender: UIStoryboardSegue) {
         if let sourceViewController = sender.source as? MealViewController, let meal = sourceViewController.meal {
-            // Add a new meal.
-            let newIndexPath = IndexPath(row: meals.count, section: 0)
-            
-            meals.append(meal)
-            tableView.insertRows(at: [newIndexPath], with: .automatic)
+            if let selectedIndexPath = tableView.indexPathForSelectedRow {
+                // Update an existing meal.
+                meals[selectedIndexPath.row] = meal
+                tableView.reloadRows(at: [selectedIndexPath], with: .none)
+            }
+            else {
+                // Add a new meal.
+                let newIndexPath = IndexPath(row: meals.count, section: 0)
+                
+                meals.append(meal)
+                tableView.insertRows(at: [newIndexPath], with: .automatic)
+            }
         }
     }
 

iOSTemplate/MealViewController.swift

@@ -27,6 +27,14 @@ class MealViewController: UIViewController, UITextFieldDelegate, UIImagePickerCo
         // Handle the text field’s user input through delegate callbacks.
         nameTextField.delegate = self
         
+        // Set up views if editing an existing Meal.
+        if let meal = meal {
+            navigationItem.title = meal.name
+            nameTextField.text   = meal.name
+            photoImageView.image = meal.photo
+            ratingControl.rating = meal.rating
+        }
+        
         // Enable the Save button only if the text field has a valid Meal name.
         updateSaveButtonState()
     }
@@ -72,7 +80,18 @@ class MealViewController: UIViewController, UITextFieldDelegate, UIImagePickerCo
     // MARK: Navigation
     
     @IBAction func cancel(_ sender: UIBarButtonItem) {
-         dismiss(animated: true, completion: nil)
+        // Depending on style of presentation (modal or push presentation), this view controller needs to be dismissed in two different ways.
+        let isPresentingInAddMealMode = presentingViewController is UINavigationController
+        
+        if isPresentingInAddMealMode {
+            dismiss(animated: true, completion: nil)
+        }
+        else if let owningNavigationController = navigationController{
+            owningNavigationController.popViewController(animated: true)
+        }
+        else {
+            fatalError("The MealViewController is not inside a navigation controller.")
+        }
     }
     
     // This method lets you configure a view controller before it's presented.