Java boolean array instantiating as null

Question

I'm creating a boolean array pre-populated with false values. I understand that I don't have to declare false values as they are automatically assigned however I've been trying different methods to try and solve the problem.

package com.bignerdranch.android.geoquiz;

import android.app.ActionBar;
import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;


public class QuizActivity extends ActionBarActivity {

    private static final String TAG = "QuizActivity";
    private static final String KEY_INDEX = "index";

    private Button mTrueButton;
    private Button mFalseButton;
    private Button mNextButton;
    private Button mCheatButton;
    private TextView mQuestionTextView;

    private TrueFalse[] mQuestionBank = new TrueFalse[] {
        new TrueFalse(R.string.question_oceans, true),
        new TrueFalse(R.string.question_mideast, false),
        new TrueFalse(R.string.question_africa, false),
        new TrueFalse(R.string.question_americas, true),
        new TrueFalse(R.string.question_asia, true),
    };

    private int mCurrentIndex = 0;

    private boolean mIsCheater;

    private boolean[] mCheatedAnswers = new boolean[] {false, false, false, false, false};

I have a breakpoint on the last line, and when the program breaks here the mCheatedAnswers is instantiated as null. I don't understand why as I have given it a boolean array - does anyone know why this could be?

The previous variables all have the correct values assigned to them when I check them in the debug mode.

score 3 · Accepted Answer · answered Feb 21 '15 at 21:59

3

If you've put the breakpoint on the last line, then when it hits, the assignment hasn't executed yet.

If you put a breakpoint in the constructor body - or just step over the line - you'll find the value is assigned appropriately. (It would be simpler just to use new boolean[5], mind you... false is the default value... Mind you, it would probably be better to have a class which included the question and whether or not the user cheated. Then you'd only need one collection.)

answered Feb 21 '15 at 21:59

Jon Skeet

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Ahh thank you. Yeah I only declared false as not declaring them didn't seem to work at the time. Good suggestion changing the class - I didn't think of that – algorhythm Feb 21 '15 at 22:19

Java boolean array instantiating as null

1 Answers1