java - 错误不断崩溃 E/AndroidRuntime : FATAL EXCEPTION: main

Question

这个问题已经有答案了:

What causes a java.lang.ArrayIndexOutOfBoundsException and how do I prevent it? (25 个回答)

已关闭 5 年前。

您好，我是一名学生，我的任务量严重重载，而且我的其中一项作品总是崩溃。每当我启动该应用程序时，它就会停止工作。

我是 Android Studio 的新手，我需要更多知识，谢谢!

01-19 22:55:31.562 26778-26778/? E/AndroidRuntime: FATAL EXCEPTION: main
                                               Process: ict402.germio.examplequiz, PID: 26778
                                               java.lang.RuntimeException: Unable to start activity ComponentInfo{ict402.germio.examplequiz/ict402.germio.examplequiz.MainActivity}: java.lang.ArrayIndexOutOfBoundsException: length=3; index=3
                                                   at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2779)
                                                   at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2844)
                                                   at android.app.ActivityThread.-wrap12(ActivityThread.java)
                                                   at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1572)
                                                   at android.os.Handler.dispatchMessage(Handler.java:110)
                                                   at android.os.Looper.loop(Looper.java:203)
                                                   at android.app.ActivityThread.main(ActivityThread.java:6361)
                                                   at java.lang.reflect.Method.invoke(Native Method)
                                                   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1063)
                                                   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:924)
                                                Caused by: java.lang.ArrayIndexOutOfBoundsException: length=3; index=3
                                                   at ict402.germio.examplequiz.Question.getChoice4(Question.java:38)
                                                   at ict402.germio.examplequiz.MainActivity.updateQuestion(MainActivity.java:120)
                                                   at ict402.germio.examplequiz.MainActivity.onCreate(MainActivity.java:49)
                                                   at android.app.Activity.performCreate(Activity.java:6675)
                                                   at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
                                                   at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2732)
                                                   at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2844) 
                                                   at android.app.ActivityThread.-wrap12(ActivityThread.java) 
                                                   at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1572) 
                                                   at android.os.Handler.dispatchMessage(Handler.java:110) 
                                                   at android.os.Looper.loop(Looper.java:203) 
                                                   at android.app.ActivityThread.main(ActivityThread.java:6361) 
                                                   at java.lang.reflect.Method.invoke(Native Method) 
                                                   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1063) 
                                                   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:924)

这是我在 MainActivity.java 中的代码

    package ict402.germio.examplequiz;

import android.content.DialogInterface;
import android.content.Intent;
import android.support.v7.app.AlertDialog;
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 java.util.Random;

public class MainActivity extends AppCompatActivity {

Button choice1, choice2, choice3, choice4, quit;

TextView score, question;

private Question mQuestions = new Question();

private String mAnswer;
private int mScore = 0;
private int mQuestionsLength = mQuestions.mQuestions.length;
Random r;

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

    r = new Random();


    //Buttons
    choice1 = findViewById(R.id.choice1);
    choice2 = findViewById(R.id.choice2);
    choice3 = findViewById(R.id.choice3);
    choice4 = findViewById(R.id.choice4);
    quit = findViewById(R.id.quit);

    //TextViews
    score = findViewById(R.id.score);
    question =  findViewById(R.id.question);

    score.setText("Score: " + mScore);

    updateQuestion(r.nextInt(mQuestionsLength));


    choice1.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            if (choice1.getText() == mAnswer) {
                mScore++;
                score.setText("Score: " + mScore);
                updateQuestion(r.nextInt(mQuestionsLength));
            } else {
                gameOver();
            }


        }
    });
    choice2.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            if (choice2.getText() == mAnswer) {
                mScore++;
                score.setText("Score: " + mScore);
                updateQuestion(r.nextInt(mQuestionsLength));
            } else {
                gameOver();
            }
        }
    });
    choice3.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            if (choice3.getText() == mAnswer) {
                mScore++;
                score.setText("Score: " + mScore);
                updateQuestion(r.nextInt(mQuestionsLength));
            } else {
                gameOver();
            }
        }
    });
    choice4.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            if (choice4.getText() == mAnswer) {
                mScore++;
                score.setText("Score: " + mScore);
                updateQuestion(r.nextInt(mQuestionsLength));
            } else {
                gameOver();
            }
        }
    });
    quit.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

        }
    });

}


private void updateQuestion(int num) {

    question.setText(mQuestions.getQuestion(num));

    choice1.setText(mQuestions.getChoice1(num));
    choice2.setText(mQuestions.getChoice2(num));
    choice3.setText(mQuestions.getChoice3(num));
    choice4.setText(mQuestions.getChoice4(num));


    mAnswer = mQuestions.getCorrectAnswer(num);


}


private void gameOver() {
    AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(MainActivity.this);
    alertDialogBuilder
            .setMessage("Game Over! Your Score is " + mScore + "pts.")
            .setCancelable(false)
            .setPositiveButton("NEW GAME",
                    new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialogInterface, int i) {

                            startActivity(new Intent(getApplicationContext(), MainActivity.class));

                        }
                    })
            .setNegativeButton("EXIT",
                    new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialogInterface, int i) {

                            finish();

                        }
                    });

    AlertDialog alertDialog = alertDialogBuilder.create();
    alertDialog.show();

}
}

这是我的 Question.java Activity

package ict402.germio.examplequiz;

公开课问题{

public String mQuestions [] = {
        "Complete the Statement Pogi si _________.",
        "What is the our Company Name?",
        "What is the Filipino word for Verb?",
        "Neil armstrong stepping onto the _________."

};

private String mChoices [][] = {
        {"Neil", "Ranier", "Jason"},
        {"Google Inc.", "innoTech", "STI"},
        {"Panguri", "Pandesal", "Panaguri"},
        {"Jupiter", "Moon", "Tae ng Kalabaw"}
};
private String mCorrectAnswers[] = {"Neil", "innoTech", "Pandesal", "Tae ng Kalabaw"};

public String getQuestion(int a) {
    String question = mQuestions[a];
    return question;
}
public String getChoice1(int a) {
    String choice = mChoices[a][0];
    return choice;
}
public String getChoice2(int a) {
    String choice = mChoices[a][1];
    return choice;
}
public String getChoice3(int a) {
    String choice= mChoices[a][2];
    return choice;
}
public String getChoice4(int a) {
    String choice = mChoices[a][3];
    return choice;
}

public String getCorrectAnswer(int a) {
    String answer = mCorrectAnswers[a];
    return answer;
}

}

Answer 1

您遇到 ArrayIndexOutOfBoundsException 问题。这意味着“您正在尝试触摸数组中不存在的元素”

这是因为您有 mChoices[a][3] 但 mChoices 的所有元素只有 3 个元素，这意味着只有索引 [0,1, 2]存在