我正在创建测验应用程序并将 SQLite 数据库文件导入到我的 Android 项目中，如下所示：
它只有一个id，实际问题，正确答案时，3个错误答案和问题的难度。id 有数字，问题和答案有文本类型，因为我想在他们的字段中添加数字和文本，而难度有数字类型。所以我只是将此文件导入到名为dbQuestion的资产文件夹中并尝试运行我的应用程序，按下播放按钮，它会从数据库中打开第一个问题，但是当我检查单选按钮并按下下一个问题时，我收到以下错误：
08-08 06:42:15.266: D/AndroidRuntime(2459): Shutting down VM
08-08 06:42:15.266: W/dalvikvm(2459): threadid=1: thread exiting with uncaught exception (group=0x414c4700)
08-08 06:42:15.367: E/AndroidRuntime(2459): FATAL EXCEPTION: main
08-08 06:42:15.367: E/AndroidRuntime(2459): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.tmm.android.chuck/com.tmm.android.chuck.QuestionActivity}: java.lang.IndexOutOfBoundsException: Invalid index 1, size is 1
08-08 06:42:15.367: E/AndroidRuntime(2459): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
08-08 06:42:15.367: E/AndroidRuntime(2459): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
08-08 06:42:15.367: E/AndroidRuntime(2459): at android.app.ActivityThread.access$600(ActivityThread.java:141)
08-08 06:42:15.367: E/AndroidRuntime(2459): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
08-08 06:42:15.367: E/AndroidRuntime(2459): at android.os.Handler.dispatchMessage(Handler.java:99)
08-08 06:42:15.367: E/AndroidRuntime(2459): at android.os.Looper.loop(Looper.java:137)
08-08 06:42:15.367: E/AndroidRuntime(2459): at android.app.ActivityThread.main(ActivityThread.java:5103)
08-08 06:42:15.367: E/AndroidRuntime(2459): at java.lang.reflect.Method.invokeNative(Native Method)
08-08 06:42:15.367: E/AndroidRuntime(2459): at java.lang.reflect.Method.invoke(Method.java:525)
08-08 06:42:15.367: E/AndroidRuntime(2459): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
08-08 06:42:15.367: E/AndroidRuntime(2459): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
08-08 06:42:15.367: E/AndroidRuntime(2459): at dalvik.system.NativeStart.main(Native Method)
08-08 06:42:15.367: E/AndroidRuntime(2459): Caused by: java.lang.IndexOutOfBoundsException: Invalid index 1, size is 1
08-08 06:42:15.367: E/AndroidRuntime(2459): at java.util.ArrayList.throwIndexOutOfBoundsException(ArrayList.java:255)
08-08 06:42:15.367: E/AndroidRuntime(2459): at java.util.ArrayList.get(ArrayList.java:308)
08-08 06:42:15.367: E/AndroidRuntime(2459): at com.tmm.android.chuck.quiz.GamePlay.getNextQuestion(GamePlay.java:112)
08-08 06:42:15.367: E/AndroidRuntime(2459): at com.tmm.android.chuck.QuestionActivity.onCreate(QuestionActivity.java:39)
08-08 06:42:15.367: E/AndroidRuntime(2459): at android.app.Activity.performCreate(Activity.java:5133)
08-08 06:42:15.367: E/AndroidRuntime(2459): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
08-08 06:42:15.367: E/AndroidRuntime(2459): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
08-08 06:42:15.367: E/AndroidRuntime(2459): ... 11 more
08-08 06:42:19.576: D/dalvikvm(2485): GC_FOR_ALLOC freed 67K, 6% free 2844K/3016K, paused 187ms, total 197ms
08-08 06:42:20.756: D/gralloc_goldfish(2485): Emulator without GPU emulation detected.
这就是我的 DbHelper.class 的样子：
package com.tmm.android.chuck.db;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import com.tmm.android.chuck.quiz.Question;
/**
* @author robert.hinds
*
*/
public class DBHelper extends SQLiteOpenHelper {
// The Android's default system path of your application database
private static String DB_PATH = "/data/data/com.tmm.android.chuck/databases/";
private static String DB_NAME = "dbQuestion";
private SQLiteDatabase myDataBase;
private final Context myContext;
/**
* Constructor Takes and keeps a reference of the passed context in order to
* access to the application assets and resources.
*
* @param context
*/
public DBHelper(Context context) {
super(context, DB_NAME, null, 1);
this.myContext = context;
}
/**
* Creates a empty database on the system and rewrites it with your own
* database.
* */
public void createDataBase() throws IOException {
boolean dbExist = checkDataBase();
if (!dbExist) {
// By calling this method and empty database will be created into
// the default system path
// of your application so we are gonna be able to overwrite that
// database with our database.
this.getReadableDatabase();
try {
copyDataBase();
} catch (IOException e) {
throw new Error("Error copying database");
}
}
}
/**
* Check if the database already exist to avoid re-copying the file each
* time you open the application.
*
* @return true if it exists, false if it doesn't
*/
private boolean checkDataBase() {
File dbFile = myContext.getDatabasePath(DB_NAME);
return dbFile.exists();
}
/**
* Copies your database from your local assets-folder to the just created
* empty database in the system folder, from where it can be accessed and
* handled. This is done by transfering bytestream.
* */
private void copyDataBase() throws IOException {
// Open your local db as the input stream
InputStream myInput = myContext.getAssets().open(DB_NAME);
// Path to the just created empty db
String outFileName = DB_PATH + DB_NAME;
// Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
// transfer bytes from the inputfile to the outputfile
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer)) > 0) {
myOutput.write(buffer, 0, length);
}
// Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
}
public void openDataBase() throws SQLException {
// Open the database
String myPath = DB_PATH + DB_NAME;
myDataBase = SQLiteDatabase.openDatabase(myPath, null,
SQLiteDatabase.OPEN_READONLY);
}
@Override
public synchronized void close() {
if (myDataBase != null)
myDataBase.close();
super.close();
}
@Override
public void onCreate(SQLiteDatabase db) {
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
// Add your public helper methods to access and get content from the
// database.
// You could return cursors by doing "return myDataBase.query(....)" so it'd
// be easy
// to you to create adapters for your views.
public List<Question> getQuestionSet(int difficulty, int numQ) {
List<Question> questionSet = new ArrayList<Question>();
Cursor c = myDataBase.rawQuery(
"SELECT * FROM QUESTIONS WHERE DIFFICULTY=" + difficulty
+ " ORDER BY RANDOM() LIMIT " + numQ, null);
while (c.moveToNext()) {
// Log.d("QUESTION", "Question Found in DB: " + c.getString(1));
Question q = new Question();
q.setQuestion(c.getString(1));
q.setAnswer(c.getString(2));
q.setOption1(c.getString(3));
q.setOption2(c.getString(4));
q.setOption3(c.getString(5));
q.setRating(difficulty);
questionSet.add(q);
}
return questionSet;
}
}
游戏类：
/**
*
*/
package com.tmm.android.chuck.quiz;
import java.util.ArrayList;
import java.util.List;
/**
* @author robert.hinds
*
* This class represents the current game being played
* tracks the score and player details
*
*/
public class GamePlay {
private int numRounds;
private int difficulty;
private String playerName;
private int right;
private int wrong;
private int round;
private List<Question> questions = new ArrayList<Question>();
/**
* @return the playerName
*/
public String getPlayerName() {
return playerName;
}
/**
* @param playerName the playerName to set
*/
public void setPlayerName(String playerName) {
this.playerName = playerName;
}
/**
* @return the right
*/
public int getRight() {
return right;
}
/**
* @param right the right to set
*/
public void setRight(int right) {
this.right = right;
}
/**
* @return the wrong
*/
public int getWrong() {
return wrong;
}
/**
* @param wrong the wrong to set
*/
public void setWrong(int wrong) {
this.wrong = wrong;
}
/**
* @return the round
*/
public int getRound() {
return round;
}
/**
* @param round the round to set
*/
public void setRound(int round) {
this.round = round;
}
/**
* @param difficulty the difficulty to set
*/
public void setDifficulty(int difficulty) {
this.difficulty = difficulty;
}
/**
* @return the difficulty
*/
public int getDifficulty() {
return difficulty;
}
/**
* @param questions the questions to set
*/
public void setQuestions(List<Question> questions) {
this.questions = questions;
}
/**
* @param q the question to add
*/
public void addQuestions(Question q) {
this.questions.add(q);
}
/**
* @return the questions
*/
public List<Question> getQuestions() {
return questions;
}
public Question getNextQuestion(){
//get the question
Question next = questions.get(this.getRound());
//update the round number to the next round
this.setRound(this.getRound()+1);
return next;
}
/**
* method to increment the number of correct answers this game
*/
public void incrementRightAnswers(){
right ++;
}
/**
* method to increment the number of incorrect answers this game
*/
public void incrementWrongAnswers(){
wrong ++;
}
/**
* @param numRounds the numRounds to set
*/
public void setNumRounds(int numRounds) {
this.numRounds = numRounds;
}
/**
* @return the numRounds
*/
public int getNumRounds() {
return numRounds;
}
/**
* method that checks if the game is over
* @return boolean
*/
public boolean isGameOver(){
return (getRound() >= getNumRounds());
}
}
感谢任何帮助:)
这是我的整个项目->> https://www.dropbox.com/s/e7jl14b1503aj6v/AndroidChuckQuiz-master.rar