android - Androidデータベースがタブレットで読み取れない

Question

基本的に私が作成しているのは、データベースから質問とその質問のそれぞれのオプションを読み取るクイズアプリケーションです。このアプリはタブレット用なので、画面の左側に質問のリスト (データベース内の質問の数に基づいて作成されたもの) が表示され、右側には質問と 4 つのオプションが表示されます。私が抱えている問題は、エミュレーターでは完全に動作しますが、タブレットでは動作しないことです。bin フォルダーから .apk を取得してタブレットにインストールしましたが、データベースを正常に読み取っていないようです。投稿しようとしているコードがお粗末に見える場合は申し訳ありません。Android を使用するのはこれが初めてであり、私が行っていることはすべて、インターネットで読んださまざまなチュートリアルで読んだ内容に基づいています。 .

これはデータベースヘルパーです。

//Declaration of the Questions Database
public class DBHelper extends SQLiteOpenHelper{
//Columns to be created in the table questions
public static final String TABLE_QUESTIONS = "questions";
public static final String COLUMN_QUESTIONID = "_questionid";
public static final String COLUMN_QUESTION = "question";
public static final String COLUMN_EXPLANATION = "explanation";
public static final String COLUMN_QIMAGE = "questionimage";
public static final String COLUMN_EIMAGE = "explanationimage";
public static final String COLUMN_MODULEID = "moduleid";
//***************************************************************//
//Columns to be created in the table options
public static final String TABLE_OPTIONS = "options";
public static final String COLUMN_OPTIONID = "_optionid";
public static final String COLUMN_OPTION = "option";
public static final String COLUMN_CORRECTANSWER = "correctanswer";
//public static final String COLUMN_QUESTIONID = "questionid";
//***************************************************************//
//Database name and version
private static final String DATABASE_NAME = "discipulus.db";
private static final int DATABASE_VERSION = 1;

// Database creation SQL statement of questions table
private static final String QUESTIONS_CREATE = "CREATE TABLE " + TABLE_QUESTIONS + "(" + COLUMN_QUESTIONID + " integer primary key autoincrement, " 
        + COLUMN_QUESTION + " text not null, " 
        + COLUMN_EXPLANATION + " text not null, "
        + COLUMN_QIMAGE + " text not null, "
        + COLUMN_EIMAGE + " text not null, "
        + COLUMN_MODULEID + " integer not null);";

private static final String OPTIONS_CREATE = "CREATE TABLE " + TABLE_OPTIONS + "(" + COLUMN_OPTIONID + " integer primary key autoincrement, " 
        + COLUMN_OPTION + " text not null, " 
        + COLUMN_CORRECTANSWER + " integer not null, "
        + COLUMN_QUESTIONID + " integer not null);";

public DBHelper(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
}

@Override
public void onCreate(SQLiteDatabase database) {
    database.execSQL(QUESTIONS_CREATE);
    database.execSQL(OPTIONS_CREATE);
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    Log.w(DBHelper.class.getName(),
            "Upgrading database from version " + oldVersion + " to "
                    + newVersion + ", which will destroy all old data");
    db.execSQL("DROP TABLE IF EXISTS " + TABLE_QUESTIONS);
    db.execSQL("DROP TABLE IF EXISTS " + TABLE_OPTIONS);
    onCreate(db);
}
}

public class QuestionDataSource {
private SQLiteDatabase database;
private DBHelper dbHelper;
private String[] allColumns = { DBHelper.COLUMN_QUESTIONID, DBHelper.COLUMN_QUESTION, DBHelper.COLUMN_EXPLANATION, 
    DBHelper.COLUMN_QIMAGE, DBHelper.COLUMN_EIMAGE, DBHelper.COLUMN_MODULEID };

public QuestionDataSource(Context context) {
    dbHelper = new DBHelper(context);
}

public void open() throws SQLException {
    database = dbHelper.getWritableDatabase();
}

public void close() {
    dbHelper.close();
}

これはHelper表の質問です

public Question createQuestion(String question, String explanation, String questionImage, String explanationImage, int moduleID) {
    ContentValues values = new ContentValues();
    values.put(DBHelper.COLUMN_QUESTION, question);
    values.put(DBHelper.COLUMN_EXPLANATION, explanation);
    values.put(DBHelper.COLUMN_QIMAGE, questionImage);
    values.put(DBHelper.COLUMN_EIMAGE, explanationImage);
    values.put(DBHelper.COLUMN_MODULEID, moduleID);
    long insertID  = database.insert(DBHelper.TABLE_QUESTIONS, null, values);

    Cursor cursor = database.query(DBHelper.TABLE_QUESTIONS, allColumns, DBHelper.COLUMN_QUESTIONID + " = " + insertID, null, null, 
            null, null);
    cursor.moveToFirst();
    Question newQuestion = cursorToQuestion(cursor);
    cursor.close();
    return newQuestion;
}

public List<Question> getAllQuestions() {
    List<Question> questions = new ArrayList<Question>();
    Cursor cursor = database.query(DBHelper.TABLE_QUESTIONS, allColumns, null, null, null, null, null);
    cursor.moveToFirst();
    while (!cursor.isAfterLast()) {
        Question question = cursorToQuestion(cursor);
        questions.add(question);
        cursor.moveToNext();
    }
    cursor.close();
    return questions;
}

private Question cursorToQuestion(Cursor cursor) {
    Question question = new Question();
    question.setQuestionID(cursor.getInt(0));
    question.setQuestion(cursor.getString(1));
    question.setExplanation(cursor.getString(2));
    question.setQuestionImage(cursor.getString(3));
    question.setExplanationImage(cursor.getString(4));
    question.setModuleId(cursor.getInt(5));
    return question;
}
}

そして、これはテーブルオプションのヘルパーです

public class OptionDataSource {
private SQLiteDatabase database;
private DBHelper dbHelper;
private String[] allColumns = { DBHelper.COLUMN_OPTIONID, DBHelper.COLUMN_OPTION, DBHelper.COLUMN_CORRECTANSWER, 
    DBHelper.COLUMN_QUESTIONID };

public OptionDataSource(Context context) {
    dbHelper = new DBHelper(context);
}

public void open() throws SQLException {
    database = dbHelper.getWritableDatabase();
}

public void close() {
    dbHelper.close();
}

public Option createOption(String option, int correctAnswer, int questionID) {
    ContentValues values = new ContentValues();
    values.put(DBHelper.COLUMN_OPTION, option);
    values.put(DBHelper.COLUMN_CORRECTANSWER, correctAnswer);
    values.put(DBHelper.COLUMN_QUESTIONID, questionID);
    long insertID  = database.insert(DBHelper.TABLE_OPTIONS, null, values);
    Cursor cursor = database.query(DBHelper.TABLE_OPTIONS, allColumns, DBHelper.COLUMN_OPTIONID + " = " + insertID, null, null, 
            null, null);
    cursor.moveToFirst();
    Option newOption = cursorToOption(cursor);
    cursor.close();
    return newOption;
}

public List<Option> getAllOptions() {
    List<Option> options = new ArrayList<Option>();
    Cursor cursor = database.query(DBHelper.TABLE_OPTIONS, allColumns, null, null, null, null, null);
    cursor.moveToFirst();
    while (!cursor.isAfterLast()) {
        Option option = cursorToOption(cursor);
        options.add(option);
        cursor.moveToNext();
    }
    cursor.close();
    return options;
}

public List<Option> getOptions(int qID) {
    List<Option> options = new ArrayList<Option>();
    String MY_QUERY = "SELECT * FROM options WHERE _questionid = " + qID + ";";
    Cursor cursor = database.rawQuery(MY_QUERY, null);
    cursor.moveToFirst();
    while (!cursor.isAfterLast()) {
        Option option = cursorToOption(cursor);
        options.add(option);
        cursor.moveToNext();
    }
    cursor.close();
    return options;
}

private Option cursorToOption(Cursor cursor) {
    Option option = new Option();
    option.setOptionID(cursor.getInt(0));
    option.setOption(cursor.getString(1));
    int cAnswer = cursor.getInt(2);
    if (cAnswer == 0) {
        option.setCorrectAnswer(false);
    }else {
        option.setCorrectAnswer(true);
    }
    option.setQuestionID(cursor.getInt(3));
    return option;
}
}

そして、これはMainActivityクラスです：

public class MainActivity extends ListActivity {
private QuestionDataSource dataSourceQuestions;
private OptionDataSource dataSourceOptions;
ArrayList<String> listItems = new ArrayList<String>();
ArrayAdapter<String> adapter;

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

    dataSourceQuestions = new QuestionDataSource(this);
    dataSourceQuestions.open();

    dataSourceOptions = new OptionDataSource(this);
    dataSourceOptions.open();

    List<Question> questions = dataSourceQuestions.getAllQuestions();
    int qnCount = questions.size();
    for(Question qn : questions) {
        TextView pregunta = (TextView) findViewById(R.id.textView1);
        pregunta.setText(qn.getQuestion());
    }
    for (int i = 0; i < qnCount; i++) {
        listItems.add("Question " + (i + 1));
    }
    listItems.add("Question 3");
    adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, listItems);
    setListAdapter(adapter);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.activity_main, menu);
    return true;
}

protected void onListItemClick(ListView l, View v, int position, long id) {
    List<Question> questions = dataSourceQuestions.getAllQuestions();
    TextView pregunta = (TextView) findViewById(R.id.textView1);
    pregunta.setText(questions.get(position).getQuestion());
    int questionID = questions.get(position).getQuestionID();
    setRadioButtons(questionID);
}

private void setRadioButtons(int questionID) {
    List<Option> options = dataSourceOptions.getOptions(questionID);

    RadioButton rdb1 = (RadioButton) findViewById(R.id.rdbOption1);
    rdb1.setText(options.get(0).getOption());

    RadioButton rdb2 = (RadioButton) findViewById(R.id.rdbOption2);
    rdb2.setText(options.get(1).getOption());

    RadioButton rdb3 = (RadioButton) findViewById(R.id.rdbOption3);
    rdb3.setText(options.get(2).getOption());

    RadioButton rdb4 = (RadioButton) findViewById(R.id.rdbOption4);
    rdb4.setText(options.get(3).getOption());
}
}

誰かがこの問題で私を助けることができれば、私はとても感謝しています. 繰り返しますが、私が抱えている問題は、エミュレーターで正常に動作することですが、タブレットで実行するとデータベースを読み取っていないようです (タブレットに .apk をインストールします)。

score 0 · Accepted Answer

0

onCreate()代わりに挿入クエリを挿入するMainActivityと、完全に機能しました。

于 2012-09-11T20:17:33.893 に答える

android - Androidデータベースがタブレットで読み取れない

1 に答える 1

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