Simple App Crashes

Question

Hey so I'm building a math game from an educational book. I had asked a similar question, and uninstalling then reinstalling android helped, the same code ran. Now, I've gotten further in the code and can't seem to find an error. I have a feeling it may be the placement of my setQuestion() method in the onClick method of the GameActivity.java. Also, the score and level elements aren't updating, not sure if that's part of the problem, but I feel like the code is just crashing before it updates them. If runs (in both an emulator and on my phone) until the user selects an answer, and then it crashes. Here is my code:

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.baylamafia.snzyt.mathgamechapter2.MainActivity">

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:text="My Math Game"
    android:id="@+id/textView"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:textSize="30sp" />

<ImageView
    android:layout_width="150dp"
    android:layout_height="150dp"
    android:id="@+id/imageView"
    android:layout_below="@+id/textView"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="20dp" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Play"
    android:id="@+id/buttonPlay"
    android:layout_centerVertical="true"
    android:layout_alignEnd="@+id/button2"
    android:layout_alignStart="@+id/button2" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="High Scores"
    android:id="@+id/button2"
    android:layout_below="@+id/buttonPlay"
    android:layout_centerHorizontal="true" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Quit"
    android:id="@+id/button3"
    android:layout_below="@+id/button2"
    android:layout_alignStart="@+id/button2"
    android:layout_alignEnd="@+id/button2" />

MainActivity.java

package com.baylamafia.snzyt.mathgamechapter2;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity implements     View.OnClickListener{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button buttonPlay = (Button)findViewById(R.id.buttonPlay);
        buttonPlay.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        Intent i;
        i = new Intent(this, GameActivity.class);
        startActivity(i);
    }
}

activity_game.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.baylamafia.snzyt.mathgamechapter2.GameActivity">

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:text="2"
    android:id="@+id/textPartA"
    android:textSize="70sp"
    android:layout_alignParentTop="true"
    android:layout_alignParentStart="true"
    android:layout_alignBottom="@+id/textOperator" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:text="x"
    android:id="@+id/textOperator"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:textSize="70sp" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:text="2"
    android:id="@+id/textPartB"
    android:textSize="70sp"
    android:layout_alignTop="@+id/textOperator"
    android:layout_alignParentEnd="true"
    android:layout_alignBottom="@+id/textOperator" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:text="="
    android:id="@+id/textView2"
    android:textIsSelectable="true"
    android:layout_below="@+id/textOperator"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="50dp" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="3"
    android:id="@+id/buttonChoice1"
    android:layout_alignTop="@+id/buttonChoice2"
    android:layout_toStartOf="@+id/buttonChoice2"
    android:textSize="40sp" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="4"
    android:id="@+id/buttonChoice2"
    android:layout_alignParentBottom="true"
    android:layout_centerHorizontal="true"
    android:layout_marginBottom="164dp"
    android:textSize="40sp" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="7"
    android:id="@+id/buttonChoice3"
    android:layout_alignTop="@+id/buttonChoice2"
    android:layout_toEndOf="@+id/buttonChoice2"
    android:textSize="40sp" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:text="Score: 999"
    android:id="@+id/textScore"
    android:layout_alignParentBottom="true"
    android:layout_alignParentStart="true" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:text="Level: 4"
    android:id="@+id/textLevel"
    android:layout_alignTop="@+id/textScore"
    android:layout_alignEnd="@+id/textPartB" />

GameActivity.java

package com.baylamafia.snzyt.mathgamechapter2;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import org.w3c.dom.Text;

import java.util.Random;

public class GameActivity extends AppCompatActivity implements     View.OnClickListener{

    int correctAnswer;
    Button buttonObjectChoice1;
    Button buttonObjectChoice2;
    Button buttonObjectChoice3;
    TextView textObjectPartA;
    TextView textObjectPartB;
    TextView textObjectScore;
    TextView textObjectLevel;
    int currentScore = 0;
    int currentLevel = 1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_game);

    /*here we get a working object based on either the button or TextView class and base as well
    as link our new objects directly to the appropriate UI elements that we created previously
     */

        textObjectPartA =
                (TextView)findViewById(R.id.textPartA);

        textObjectPartB =
                (TextView)findViewById(R.id.textPartB);

        buttonObjectChoice1 =
                (Button)findViewById(R.id.buttonChoice1);

        buttonObjectChoice2 =
                (Button)findViewById(R.id.buttonChoice2);

        buttonObjectChoice3 =
                (Button)findViewById(R.id.buttonChoice3);

        buttonObjectChoice1.setOnClickListener(this);
        buttonObjectChoice2.setOnClickListener(this);
        buttonObjectChoice3.setOnClickListener(this);

        setQuestion();
    }

    void setQuestion(){
    //generate the parts of the question
        int numberRange = currentLevel * 3;
        Random randInt = new Random();

        int partA = randInt.nextInt(numberRange);
        partA++;

        int partB = randInt.nextInt(numberRange);
        partB++;

        correctAnswer = partA * partB;
        int wrongAnswer1 = correctAnswer-2;
        int wrongAnswer2 = correctAnswer+2;

        textObjectPartA.setText(""+partA);
        textObjectPartB.setText(""+partB);

    //set the multi choice button

        int buttonLayout = randInt.nextInt(3);
        switch (buttonLayout){

            case 0:
                buttonObjectChoice1.setText(""+correctAnswer);
                buttonObjectChoice2.setText(""+wrongAnswer1);
                buttonObjectChoice3.setText(""+wrongAnswer2);
                break;

            case 1:
                buttonObjectChoice1.setText(""+wrongAnswer1);
                buttonObjectChoice2.setText(""+correctAnswer);
                buttonObjectChoice3.setText(""+wrongAnswer2);
                break;

            case 2:
                buttonObjectChoice1.setText(""+wrongAnswer1);
                buttonObjectChoice2.setText(""+wrongAnswer2);
                buttonObjectChoice3.setText(""+correctAnswer);
                break;

        }
    }

    void updateScoreAndLevel (int answerGiven) {

        if(isCorrect(answerGiven)){
            for(int i = 1; i < currentLevel; i++){
                currentScore = currentScore + i;
            }

            currentLevel++;

        }else{
            currentScore = 0;
            currentLevel = 1;
        }

        textObjectScore.setText("Score: " + currentScore);
        textObjectLevel.setText("Level: " + currentLevel);
    }

    boolean isCorrect(int answerGiven){
        boolean correctTrueOrFalse;
        if (answerGiven == correctAnswer){
            Toast.makeText(getApplicationContext(), "Well done!",     Toast.LENGTH_LONG).show();
            correctTrueOrFalse=true;
        }else{
            Toast.makeText(getApplicationContext(), "Sorry", Toast.LENGTH_LONG).show();
            correctTrueOrFalse=false;
        }

        return correctTrueOrFalse;
    }

    @Override
    public void onClick(View view){
        int answerGiven = 0;
        switch (view.getId()) {

            case R.id.buttonChoice1:
                answerGiven = Integer.parseInt("" + buttonObjectChoice1.getText());
                break;

            case R.id.buttonChoice2:
                answerGiven = Integer.parseInt("" + buttonObjectChoice2.getText());
                break;

            case R.id.buttonChoice3:
                answerGiven = Integer.parseInt("" + buttonObjectChoice3.getText());
                break;

        }

        updateScoreAndLevel(answerGiven);
        setQuestion();
    }


}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.baylamafia.snzyt.mathgamechapter2">

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity android:name=".GameActivity"></activity>
</application>

I figured it out, actually. All I had to do was move my onClick() method to just after my onCreate() method. I figured this out just by fiddling with it though. Can someone explain to me why this is? — snzy, Jun 20 '16 at 21:59
Also, my logcat goes over the character limit for my original post and comments, is there a way to post it and get around this? Maybe a link to a text file? — snzy, Jun 20 '16 at 22:00
you can use [Codeshare](http://codeshare.io) for posting extra codes — Yasin Kaçmaz, Jun 20 '16 at 22:09
you must have changed something else. Moving methods has 0 effect. — zapl, Jun 20 '16 at 22:25
zapi - nope, i literally copied and pasted the method and ran it, no other changes. not sure what the error was there. — snzy, Jun 23 '16 at 02:29

score 0 · Answer 1 · edited May 23 '17 at 12:08

Don't use getApplicationContext here:

 Toast.makeText(getApplicationContext(), "Well done!",     Toast.LENGTH_LONG).show();

Use this to use the current activity:

 Toast.makeText(this, "Well done!",     Toast.LENGTH_LONG).show();

Difference between getContext() , getApplicationContext() , getBaseContext() and "this"

For starters, get rid of all these extraneous ""+ they serve no purpose. You are adding nothing to the string:

buttonObjectChoice1.setText(""+correctAnswer); 

answerGiven = Integer.parseInt("" + buttonObjectChoice1.getText());

Also this

answerGiven = Integer.parseInt("" + buttonObjectChoice1.getText());

will fail if there is not the correct input i.e. int.

Also, I'm not sure what you are using this for import org.w3c.dom.Text.

Simple App Crashes

1 Answers1