Highlighting the correct answer in a quiz app - ios

Question

I'm new to iOS development and have been working through some online courses. In one of these we develop a quiz app and I'd like to improve my skills by improving the app beyond what is covered in the course.
The app uses a .json file as the 'database' of questions and answers. This .json file looks as follows...
{
"id" : "1",
"question": "Earth is a:",
"answers": [
"Planet",
"Meteor",
"Star",
"Asteroid"
],
"difficulty": "1"
}
...and just keeps going for over 500 questions.
At present, the app presents the user a question with the four possible answers. In the .json file, the first answer is always the correct answer, but the app is coded to shuffle the answers so that the correct answer is not always listed first.
The app is also coded so that the four buttons (I use four different coloured images for the buttons) displaying the answers are disabled and also dimmed in appearance after the user makes a selection, except that the button they selected is not dimmed so that their choice is highlighted.
What I would like to do is change this so that the button with the correct answer is highlighted instead, as a way of notifying the user what the correct answer was.
I'm using the following code to load the questions and answers and to shuffle the answers:
func loadAllQuestionsAndAnswers()
{
let path = NSBundle.mainBundle().pathForResource("content", ofType: "json")
let jsonData : NSData = NSData(contentsOfFile: path!)!
allEntries = (try! NSJSONSerialization.JSONObjectWithData(jsonData, options: NSJSONReadingOptions.MutableContainers)) as! NSArray
//println(allEntries)
}
func loadQuestion(index : Int)
{
let entry : NSDictionary = allEntries.objectAtIndex(index) as! NSDictionary
let question : NSString = entry.objectForKey("question") as! NSString
let arr : NSMutableArray = entry.objectForKey("answers") as! NSMutableArray
//println(question)
//println(arr)
labelQuestion.text = question as String
let indices : [Int] = [0,1,2,3]
//let newSequence = shuffle(indices)
let newSequence = indices.shuffle()
var i : Int = 0
for(i = 0; i < newSequence.count; i++)
{
let index = newSequence[i]
if(index == 0)
{
// we need to store the correct answer index
currentCorrectAnswerIndex = i
}
let answer = arr.objectAtIndex(index) as! NSString
switch(i)
{
case 0:
buttonA.setTitle(answer as String, forState: UIControlState.Normal)
break;
case 1:
buttonB.setTitle(answer as String, forState: UIControlState.Normal)
break;
case 2:
buttonC.setTitle(answer as String, forState: UIControlState.Normal)
break;
case 3:
buttonD.setTitle(answer as String, forState: UIControlState.Normal)
break;
default:
break;
}
At present I am using this code to check the answer:
var currentCorrectAnswerIndex : Int = 0
func checkAnswer( answerNumber : Int)
{
if(answerNumber == currentCorrectAnswerIndex)
{
// we have the correct answer
labelFeedback.text = "Correct! +1"
labelFeedback.textColor = UIColor.greenColor()
score = score + 1
labelScore.text = "score: \(score)"
SaveScore()
// later we want to play a "correct" sound effect
PlaySoundCorrect()
}
else
{
// we have the wrong answer
labelFeedback.text = "Wrong answer"
labelFeedback.textColor = UIColor.redColor()
// we want to play a "incorrect" sound effect
PlaySoundWrong()
}
In terms of highlighting the buttons I was going to use coding such as:
func resetAnswerButtons()
{
buttonA.alpha = 1.0
buttonB.alpha = 1.0
buttonC.alpha = 1.0
buttonD.alpha = 1.0
buttonA.enabled = true
buttonB.enabled = true
buttonC.enabled = true
buttonD.enabled = true
}
#IBAction func PressedButtonA(sender: UIButton) {
print("button A pressed")
buttonB.alpha = 0.3
buttonC.alpha = 0.3
buttonD.alpha = 0.3
buttonA.enabled = false
buttonB.enabled = false
buttonC.enabled = false
buttonD.enabled = false
CheckAnswer(0)
}
#IBAction func PressedButtonB(sender: UIButton) {
print("button B pressed")
buttonA.alpha = 0.3
buttonC.alpha = 0.3
buttonD.alpha = 0.3
buttonA.enabled = false
buttonB.enabled = false
buttonC.enabled = false
buttonD.enabled = false
CheckAnswer(1)
}
#IBAction func PressedButtonC(sender: UIButton) {
print("button C pressed")
buttonA.alpha = 0.3
buttonB.alpha = 0.3
buttonD.alpha = 0.3
buttonA.enabled = false
buttonB.enabled = false
buttonC.enabled = false
buttonD.enabled = false
CheckAnswer(2)
}
#IBAction func PressedButtonD(sender: UIButton) {
print("button D pressed")
buttonA.alpha = 0.3
buttonB.alpha = 0.3
buttonC.alpha = 0.3
buttonA.enabled = false
buttonB.enabled = false
buttonC.enabled = false
buttonD.enabled = false
CheckAnswer(3)
}
What I can't get my head around is how to code the app so that it highlights the correct answer? At present, the above code effectively highlights the button that was pressed by dimming the alpha of the 'other' buttons. How do I get the app to identify which 'shuffled' button contains the correct answer and highlight that one instead?

Answer 1

When rolling your dice, remember the index of the button containing the right answer.
Also, you may put all buttons in an array and manipulate all of them with forall loops. That makes the code much, much cleaner and gets rid of the weird variable names and the switch case.