Migrated quiz module from Java to Kotlin (commons-app#5952)

* Rename .java to .kt

* Migrated quiz module to Kotlin

* unit test failing fixed

* unit test failing fixed

Author: Saifuddin53

app/src/main/java/fr/free/nrw/commons/quiz/QuizActivity.java

@@ -0,0 +1,154 @@
+package fr.free.nrw.commons.quiz
+
+import android.annotation.SuppressLint
+import android.content.Intent
+import android.os.Bundle
+
+import androidx.appcompat.app.AlertDialog
+import androidx.appcompat.app.AppCompatActivity
+import androidx.vectordrawable.graphics.drawable.VectorDrawableCompat
+
+import com.facebook.drawee.drawable.ProgressBarDrawable
+import com.facebook.drawee.generic.GenericDraweeHierarchyBuilder
+
+import fr.free.nrw.commons.databinding.ActivityQuizBinding
+import java.util.ArrayList
+
+import fr.free.nrw.commons.R
+
+
+class QuizActivity : AppCompatActivity() {
+
+    private lateinit var binding: ActivityQuizBinding
+    private val quizController = QuizController()
+    private var quiz = ArrayList<QuizQuestion>()
+    private var questionIndex = 0
+    private var score = 0
+
+    /**
+     * isPositiveAnswerChecked : represents yes click event
+     */
+    private var isPositiveAnswerChecked = false
+
+    /**
+     * isNegativeAnswerChecked : represents no click event
+     */
+    private var isNegativeAnswerChecked = false
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        binding = ActivityQuizBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+
+        quizController.initialize(this)
+        setSupportActionBar(binding.toolbar.toolbar)
+        binding.nextButton.setOnClickListener { notKnowAnswer() }
+        displayQuestion()
+    }
+
+    /**
+     * To move to next question and check whether answer is selected or not
+     */
+    fun setNextQuestion() {
+        if (questionIndex <= quiz.size && (isPositiveAnswerChecked || isNegativeAnswerChecked)) {
+            evaluateScore()
+        }
+    }
+
+    private fun notKnowAnswer() {
+        customAlert("Information", quiz[questionIndex].answerMessage)
+    }
+
+    /**
+     * To give warning before ending quiz
+     */
+    override fun onBackPressed() {
+        AlertDialog.Builder(this)
+            .setTitle(getString(R.string.warning))
+            .setMessage(getString(R.string.quiz_back_button))
+            .setPositiveButton(R.string.continue_message) { dialog, _ ->
+                val intent = Intent(this, QuizResultActivity::class.java)
+                dialog.dismiss()
+                intent.putExtra("QuizResult", score)
+                startActivity(intent)
+            }
+            .setNegativeButton("Cancel") { dialogInterface, _ -> dialogInterface.dismiss() }
+            .create()
+            .show()
+    }
+
+    /**
+     * To display the question
+     */
+    @SuppressLint("SetTextI18n")
+    private fun displayQuestion() {
+        quiz = quizController.getQuiz()
+        binding.question.questionText.text = quiz[questionIndex].question
+        binding.questionTitle.text = getString(R.string.question) + quiz[questionIndex].questionNumber
+
+        binding.question.questionImage.hierarchy = GenericDraweeHierarchyBuilder
+            .newInstance(resources)
+            .setFailureImage(VectorDrawableCompat.create(resources, R.drawable.ic_error_outline_black_24dp, theme))
+            .setProgressBarImage(ProgressBarDrawable())
+            .build()
+
+        binding.question.questionImage.setImageURI(quiz[questionIndex].getUrl())
+        isPositiveAnswerChecked = false
+        isNegativeAnswerChecked = false
+
+        binding.answer.quizPositiveAnswer.setOnClickListener {
+            isPositiveAnswerChecked = true
+            setNextQuestion()
+        }
+        binding.answer.quizNegativeAnswer.setOnClickListener {
+            isNegativeAnswerChecked = true
+            setNextQuestion()
+        }
+    }
+
+    /**
+     * To evaluate score and check whether answer is correct or wrong
+     */
+    fun evaluateScore() {
+        if (
+            (quiz[questionIndex].isAnswer && isPositiveAnswerChecked)
+                ||
+            (!quiz[questionIndex].isAnswer && isNegativeAnswerChecked)
+            ) {
+            customAlert(
+                getString(R.string.correct),
+                quiz[questionIndex].answerMessage
+            )
+            score++
+        } else {
+            customAlert(
+                getString(R.string.wrong),
+                quiz[questionIndex].answerMessage
+            )
+        }
+    }
+
+    /**
+     * To display explanation after each answer, update questionIndex and move to next question
+     * @param title The alert title
+     * @param message The alert message
+     */
+    fun customAlert(title: String, message: String) {
+        AlertDialog.Builder(this)
+            .setTitle(title)
+            .setMessage(message)
+            .setPositiveButton(R.string.continue_message) { dialog, _ ->
+                questionIndex++
+                if (questionIndex == quiz.size) {
+                    val intent = Intent(this, QuizResultActivity::class.java)
+                    dialog.dismiss()
+                    intent.putExtra("QuizResult", score)
+                    startActivity(intent)
+                } else {
+                    displayQuestion()
+                }
+            }
+            .create()
+            .show()
+    }
+}