how to solve errors related to scores and proceed to next round in android general knowledge quiz?

Question

i am working on android quiz. when i run it on emulator first question appear and i answer it. its stopped working. and then restart from start. i dont know where's problem in my code.

questionactivity.class

import java.util.List;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;


public class QuestionActivity extends Activity implements OnClickListener{

    private Question currentQ;
    private GamePlay currentGame;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.question);
        /**
         * Configure current game and get question
         */
        currentGame = ((CYKApplication)getApplication()).getCurrentGame();
        currentQ = currentGame.getNextQuestion();
        Button nextBtn1 = (Button) findViewById(R.id.answer1);
        nextBtn1.setOnClickListener(this);
        Button nextBtn2 = (Button) findViewById(R.id.answer2);
        nextBtn2.setOnClickListener(this);
        Button nextBtn3 = (Button) findViewById(R.id.answer3);
        nextBtn3.setOnClickListener(this);
        Button nextBtn4 = (Button) findViewById(R.id.answer4);
        nextBtn4.setOnClickListener(this);
        /**
         * Update the question and answer options..
         */
        setQuestions();

    }


    /**
     * Method to set the text for the question and answers from the current games
     * current question
     */
    private void setQuestions() {
        //set the question text from current question
        String question = Utility.capitalise(currentQ.getQuestion());
        TextView qText = (TextView) findViewById(R.id.question);
        qText.setText(question);

        //set the available options
        List<String> answers = currentQ.getQuestionOptions();
        TextView option1 = (TextView) findViewById(R.id.answer1);
        option1.setText(Utility.capitalise(answers.get(0)));

        TextView option2 = (TextView) findViewById(R.id.answer2);
        option2.setText(Utility.capitalise(answers.get(1)));

        TextView option3 = (TextView) findViewById(R.id.answer3);
        option3.setText(Utility.capitalise(answers.get(2)));

        TextView option4 = (TextView) findViewById(R.id.answer4);
        option4.setText(Utility.capitalise(answers.get(3)));
    }


    @Override
    public void onClick(View arg0) {
        //Log.d("Questions", "Moving to next question");

        if(!checkAnswer()) return;

        /**
         * check if end of game
         */
        if (currentGame.isGameOver()){
            //Log.d("Questions", "End of game! lets add up the scores..");
            //Log.d("Questions", "Questions Correct: " +            currentGame.getRight());
            //Log.d("Questions", "Questions Wrong: " + currentGame.getWrong());
            Intent i = new Intent(this, EndgameActivity.class);
            startActivity(i);
            finish();
        }
        else{
            Intent i = new Intent(this, QuestionActivity.class);
            startActivity(i);
            finish();
        }
    }




    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event)
    {
        switch (keyCode)
        {
        case KeyEvent.KEYCODE_BACK :
            return true;
        }

        return super.onKeyDown(keyCode, event);
    }


    /**
     * Check if a checkbox has been selected, and if it
     * has then check if its correct and update gamescore
     */
    private boolean checkAnswer() {
        String answer = getSelectedAnswer();

            if (currentQ.getAnswer().equalsIgnoreCase(answer))
            {
                //Log.d("Questions", "Correct Answer!");
                currentGame.incrementScore();
            }
            else{
                //Log.d("Questions", "Incorrect Answer!");
                currentGame.decrementScore();
            }
            return true;
        }

    /**
     * 
     */
    private String getSelectedAnswer() {
        Button c1 = (Button)findViewById(R.id.answer1);
        Button c2 = (Button)findViewById(R.id.answer2);
        Button c3 = (Button)findViewById(R.id.answer3);
        Button c4 = (Button)findViewById(R.id.answer4);
        if (c1.callOnClick())
        {
            return c1.getText().toString();
        }
        if (c2.callOnClick())
        {
            return c2.getText().toString();
        }
        if (c3.callOnClick())
        {
            return c3.getText().toString();
        }
        if (c4.callOnClick())
        {
            return c4.getText().toString();
        }

        return null;
    }

}

Log output:

    09-02 08:17:30.083: E/Trace(2148): error opening trace file: No such file or directory (2)
    09-02 08:17:30.193: D/dalvikvm(2148): GC_FOR_ALLOC freed 65K, 8% free 2413K/2620K, paused 26ms, total 28ms
    09-02 08:17:30.203: I/dalvikvm-heap(2148): Grow heap (frag case) to 4.553MB for 2160016-byte allocation
    09-02 08:17:30.313: D/dalvikvm(2148): GC_FOR_ALLOC freed 1K, 5% free 4521K/4732K, paused 104ms, total 104ms
    09-02 08:17:30.363: D/dalvikvm(2148): GC_CONCURRENT freed <1K, 5% free 4521K/4732K, paused 4ms+3ms, total 50ms
    09-02 08:17:30.832: D/gralloc_goldfish(2148): Emulator without GPU emulation detected.
    09-02 08:17:35.432: D/dalvikvm(2148): GC_FOR_ALLOC freed 17K, 4% free 4988K/5148K, paused 42ms, total 45ms
    09-02 08:17:35.482: I/dalvikvm-heap(2148): Grow heap (frag case) to 7.068MB for 2160016-byte allocation
    09-02 08:17:35.562: D/dalvikvm(2148): GC_CONCURRENT freed 4K, 3% free 7092K/7260K, paused 4ms+4ms, total 77ms
    09-02 08:17:36.512: I/Choreographer(2148): Skipped 764 frames!  The application may be doing too much work on its main thread.
    09-02 08:17:38.682: I/dalvikvm(2148): threadid=1: stack overflow on call to Landroid/view/View;.findViewById:LI
    09-02 08:17:38.682: I/dalvikvm(2148):   method requires 12+20+8=40 bytes, fp is 0x4205a320 (32 left)
    09-02 08:17:38.682: I/dalvikvm(2148):   expanding stack end (0x4205a300 to 0x4205a000)
    09-02 08:17:38.682: I/dalvikvm(2148): Shrank stack (to 0x4205a300, curFrame is 0x4205fec4)
    09-02 08:17:38.682: D/AndroidRuntime(2148): Shutting down VM
    09-02 08:17:38.682: W/dalvikvm(2148): threadid=1: thread exiting with uncaught exception (group=0x40a71930)
    09-02 08:17:39.092: E/AndroidRuntime(2148): FATAL EXCEPTION: main
    09-02 08:17:39.092: E/AndroidRuntime(2148): java.lang.StackOverflowError
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.ViewGroup.findViewTraversal(ViewGroup.java:3053)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.findViewById(View.java:15104)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.ViewGroup.findViewTraversal(ViewGroup.java:3053)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.findViewById(View.java:15104)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.ViewGroup.findViewTraversal(ViewGroup.java:3053)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.findViewById(View.java:15104)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.ViewGroup.findViewTraversal(ViewGroup.java:3053)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.findViewById(View.java:15104)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.Window.findViewById(Window.java:900)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.app.Activity.findViewById(Activity.java:1839)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.starchazer.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:144)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.starchazer.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.starchazer.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.callOnClick(View.java:4222)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.starchazer.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:148)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.starchazer.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.starchazer.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.callOnClick(View.java:4222)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:148)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.callOnClick(View.java:4222)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:148)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.callOnClick(View.java:4222)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:148)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.callOnClick(View.java:4222)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:148)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.callOnClick(View.java:4222)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:148)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.callOnClick(View.java:4222)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:148)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.callOnClick(View.java:4222)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:148)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.callOnClick(View.java:4222)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:148)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.callOnClick(View.java:4222)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:148)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.View.callOnClick(View.java:4222)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.getSelectedAnswer(QuestionActivity.java:148)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.checkAnswer(QuestionActivity.java:126)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at com.cyk.QuestionActivity.onClick(QuestionActivity.java:85)
    09-02 08:17:39.092: E/AndroidRuntime(2148):     at android.view.V
    09-02 08:17:39.122: D/dalvikvm(2148): GC_CONCURRENT freed 762K, 11% free 7907K/8812K, paused 69ms+5ms, total 117ms
    09-02 08:17:39.122: D/dalvikvm(2148): WAIT_FOR_CONCURRENT_GC blocked 16ms
    09-02 08:22:39.222: I/Process(2148): Sending signal. PID: 2148 SIG: 9
    09-02 08:22:39.783: E/Trace(2182): error opening trace file: No such file or directory (2)
    09-02 08:22:39.883: D/dalvikvm(2182): GC_FOR_ALLOC freed 68K, 9% free 2413K/2624K, paused 25ms, total 27ms
    09-02 08:22:39.893: I/dalvikvm-heap(2182): Grow heap (frag case) to 4.553MB for 2160016-byte allocation
    09-02 08:22:40.013: D/dalvikvm(2182): GC_FOR_ALLOC freed 1K, 5% free 4521K/4736K, paused 114ms, total 114ms
    09-02 08:22:40.063: D/dalvikvm(2182): GC_CONCURRENT freed <1K, 5% free 4521K/4736K, paused 4ms+3ms, total 49ms
    09-02 08:22:40.513: D/gralloc_goldfish(2182): Emulator without GPU emulation detected.

when i remove call to checkAnswer() method from onClick() method my game work. but then my game not check my answer right or wrong. on the other hand if i am not remove call to this method. my game works and after answering first question my app stop working and restart. can someone help me to find error in my code?

Answer 1

onClick provides you with the view that was clicked (arg0 in your code), so pass that to your checkAnswer method. Then in checkAnswer (or getSelectedAnswer) you can simply check which view was clicked and use it directly to validate the answer.

The method you use now is probably causing some kind of recursion because you invoke onClick for each button in getSelectedAnswer and that results in a stack overflow.

---

Edit: example code (untested) to illustrate the idea

@Override
public void onClick(View arg0) {

    // NEW: pass the received view to checkAnswer
    if(!checkAnswer(arg0)) return;

    if (currentGame.isGameOver()){
        //Log.d("Questions", "End of game! lets add up the scores..");
        //Log.d("Questions", "Questions Correct: " +            currentGame.getRight());
        //Log.d("Questions", "Questions Wrong: " + currentGame.getWrong());
        Intent i = new Intent(this, EndgameActivity.class);
        startActivity(i);
        finish();
    }
    else{
        Intent i = new Intent(this, QuestionActivity.class);
        startActivity(i);
        finish();
    }
}

// NEW: add view as argument to checkAnswer
private boolean checkAnswer(View v) {

    // NEW: retrieve answer from clicked view
    Button b = (Button)v;
    String answer = b.getText().toString();

    // now check if the answer is correct
    if (currentQ.getAnswer().equalsIgnoreCase(answer))  {
        //Log.d("Questions", "Correct Answer!");
        currentGame.incrementScore();
    }
    else  {
        //Log.d("Questions", "Incorrect Answer!");
        currentGame.decrementScore();
    }
    return true;
}

Since I don't exactly know how your app is laid out, I am assuming here that you have four "buttons", each with an answer set as it's caption. What the code above does is retrieve the view that was clicked and extract it's caption (text), then checks that against the correct answer. Of course since you could also NOT click one of the buttons you will probably need to check if the clicked view is indeed one of the buttons, and if not you should skip the answer checking - I have omitted this in the example code above.