Finish initial implementation of Project 2

02-guess-the-flag/Guess the Flag/Guess the Flag/Base.lproj/Main.storyboard

@@ -24,21 +24,30 @@
                                 <state key="normal" image="us">
                                     <color key="titleColor" red="0.45880425499999999" green="0.42457667529999998" blue="0.85103040929999996" alpha="1" colorSpace="custom" customColorSpace="displayP3"/>
                                 </state>
+                                <connections>
+                                    <action selector="buttonTapped:" destination="BYZ-38-t0r" eventType="touchUpInside" id="60c-f8-bO2"/>
+                                </connections>
                             </button>
-                            <button opaque="NO" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="ZzW-Kt-38n">
+                            <button opaque="NO" tag="1" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="ZzW-Kt-38n">
                                 <rect key="frame" x="87.5" y="230" width="200" height="100"/>
                                 <color key="backgroundColor" red="0.98754758880000004" green="0.35643531880000001" blue="0.43980186630000001" alpha="1" colorSpace="custom" customColorSpace="displayP3"/>
                                 <size key="titleShadowOffset" width="2" height="-2"/>
                                 <state key="normal" image="us">
                                     <color key="titleColor" red="0.45880425499999999" green="0.42457667529999998" blue="0.85103040929999996" alpha="1" colorSpace="custom" customColorSpace="displayP3"/>
                                 </state>
+                                <connections>
+                                    <action selector="buttonTapped:" destination="BYZ-38-t0r" eventType="touchUpInside" id="5VZ-Mb-yvZ"/>
+                                </connections>
                             </button>
-                            <button opaque="NO" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="NEb-PX-xnZ">
+                            <button opaque="NO" tag="2" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="NEb-PX-xnZ">
                                 <rect key="frame" x="87.5" y="360" width="200" height="100"/>
                                 <color key="backgroundColor" red="0.98754758880000004" green="0.35643531880000001" blue="0.43980186630000001" alpha="1" colorSpace="custom" customColorSpace="displayP3"/>
                                 <state key="normal" image="us">
                                     <color key="titleColor" red="0.45880425499999999" green="0.42457667529999998" blue="0.85103040929999996" alpha="1" colorSpace="custom" customColorSpace="displayP3"/>
                                 </state>
+                                <connections>
+                                    <action selector="buttonTapped:" destination="BYZ-38-t0r" eventType="touchUpInside" id="U4R-CP-ARt"/>
+                                </connections>
                             </button>
                         </subviews>
                         <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>

02-guess-the-flag/Guess the Flag/Guess the Flag/ViewController.swift

@@ -30,7 +30,8 @@ class ViewController: UIViewController {
     @IBOutlet var button3: UIButton!
     
     var currentScore = 0
-    
+    var flagChoiceKeys = [String]()
+    var correctFlagKey: String?
     
     override func viewDidLoad() {
         super.viewDidLoad()
@@ -42,15 +43,18 @@ class ViewController: UIViewController {
 
     
     func askQuestion() {
-        let flagKeys = flagFilePathsAndNames.keys.shuffled()[..<3]
+        flagChoiceKeys = Array(flagFilePathsAndNames.keys.shuffled()[..<3])
-        let flagToGuess = flagFilePathsAndNames[flagKeys.randomElement() ?? flagKeys[0]]
+        correctFlagKey = flagChoiceKeys.randomElement()
 
-        if let _flagToGuess = flagToGuess {
+        if let _key = correctFlagKey {
-            title = "Which flag belongs to \(_flagToGuess)"
+            if let flagName = flagFilePathsAndNames[_key] {
+                // 📝 If we didn't get here, that would be a serious problem that needed more robust error handling
+                title = "Which flag belongs to \(flagName)?"
+            }
         }
         
         for (index, button) in [button1, button2, button3].enumerated() {
-            button?.setImage(UIImage(named: flagKeys[index]), for: .normal)
+            button?.setImage(UIImage(named: flagChoiceKeys[index]), for: .normal)
         }
     }
     
@@ -61,5 +65,45 @@ class ViewController: UIViewController {
             button?.layer.borderColor = UIColor(red: 1.00, green: 0.28, blue: 0.38, alpha: 1.00).cgColor
         }
     }
+    
+    
+    func handleChoice(wasCorrect: Bool) {
+        if wasCorrect {
+            title = "Correct!"
+            currentScore += 1
+        } else {
+            title = "Incorrect!"
+            currentScore = min(currentScore - 3, 0)
+        }
+        
+        let responseMessage = "Your score is now \(currentScore)."
+        let alertController = UIAlertController(title: title, message: responseMessage, preferredStyle: .alert)
+        
+        alertController.addAction(
+            UIAlertAction(title: "Continue", style: .default, handler: _askAnotherQuestion)
+        )
+        
+        present(alertController, animated: true)
+    }
+    
+    
+    @IBAction func buttonTapped(_ sender: UIButton) {
+        let flagKeyChosen = flagChoiceKeys[sender.tag]
+        
+        if flagKeyChosen == correctFlagKey {
+            handleChoice(wasCorrect: true)
+        } else {
+            handleChoice(wasCorrect: false)
+        }
+    }
+    
+    /// callback for the UIAlertAction that conforms to the signature it expects
+    /// (that is, taking a UIAlertAction argument).
+    ///
+    /// All we really want to do, though, is ask another quesstion, so this function
+    /// just hides the handler implementation detail away from `askQuestion`
+    func _askAnotherQuestion(action: UIAlertAction) {
+        askQuestion()
+    }
 }