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我有一个问题，我现在正在努力解决几天。它一直给我一个错误，即我的数据库没有关闭。我从我的 sql 数据库中取出项目并将它们放在带有自定义适配器的 gridview 中。如果您单击一个项目，它将带您到另一个类（answer.java）。什么都不做并点击后退按钮不会导致错误，但是如果我调用某个函数并在此函数之后点击后退按钮，我会在按下后退按钮时收到 close() 错误。所以这是确切的错误：

    11-19 19:56:22.485: E/Database(7403): close() was never explicitly called on database '/data/data/com.test.game/databases/quizDb' 
11-19 19:56:22.485: E/Database(7403): android.database.sqlite.DatabaseObjectNotClosedException: Application did not close the cursor or database object that was opened here
11-19 19:56:22.485: E/Database(7403):   at android.database.sqlite.SQLiteDatabase.<init>(SQLiteDatabase.java:1847)
11-19 19:56:22.485: E/Database(7403):   at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:820)
11-19 19:56:22.485: E/Database(7403):   at com.test.game.db.DataBaseHelper.openDataBase(DataBaseHelper.java:117)
11-19 19:56:22.485: E/Database(7403):   at com.test.game.Answer.loadDataBase(Answer.java:179)
11-19 19:56:22.485: E/Database(7403):   at com.test.game.Answer.onClick(Answer.java:240)
11-19 19:56:22.485: E/Database(7403):   at android.view.View.performClick(View.java:2491)
11-19 19:56:22.485: E/Database(7403):   at android.view.View$PerformClick.run(View.java:9086)
11-19 19:56:22.485: E/Database(7403):   at android.os.Handler.handleCallback(Handler.java:587)
11-19 19:56:22.485: E/Database(7403):   at android.os.Handler.dispatchMessage(Handler.java:92)
11-19 19:56:22.485: E/Database(7403):   at android.os.Looper.loop(Looper.java:130)
11-19 19:56:22.485: E/Database(7403):   at android.app.ActivityThread.main(ActivityThread.java:3683)
11-19 19:56:22.485: E/Database(7403):   at java.lang.reflect.Method.invokeNative(Native Method)
11-19 19:56:22.485: E/Database(7403):   at java.lang.reflect.Method.invoke(Method.java:507)
11-19 19:56:22.485: E/Database(7403):   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:861)
11-19 19:56:22.485: E/Database(7403):   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:619)
11-19 19:56:22.485: E/Database(7403):   at dalvik.system.NativeStart.main(Native Method)

我想我找到了导致此错误的代码部分，如果我不再在 answer.java 文件中调用 myDbHelper.insertString(...) ，我就不会再收到错误了...

public void insertString(int id, int level, String field, String player) {

    Cursor c = myDataBase.rawQuery(
            "SELECT * FROM ANSWERS WHERE QUESTION_ID=" + id
                    + " AND PLAYER ='" + player + "'", null);

    myDataBase = this.getWritableDatabase();

    if (c != null) {
        myDataBase.execSQL("UPDATE ANSWERS SET " + field + "=1"
                + " WHERE QUESTION_ID=" + id + " AND LEVEL =" + level
                + " AND PLAYER='" + player + "'");
    } else {
        myDataBase
                .execSQL("INSERT INTO ANSWERS (level, player, question_id, "
                        + field + ") VALUES ("+ level + ",'" + player + "'," + id + ", 1)");
    }

    c.close();
    if (myDataBase != null) {
        myDataBase.close();

    }

}

我尝试但未解决的一件事是将其添加到我的 answer.java 文件中：

@Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if (keyCode == KeyEvent.KEYCODE_BACK) {
            if (myDbHelper != null) {
                 myDbHelper.close();
            }
return true;
        }

        return super.onKeyDown(keyCode, event);
    }

// 我的 databasehelper.java 中的 .close() 是：

@Override
public synchronized void close() {
    if (myDataBase != null)
        myDataBase.close();
    if (c != null)
        c.close();
    super.close();
}

希望有人能给我指点灯！

编辑

@sam 你的解决方案给了我这个：

11-19 19:52:42.735: E/AndroidRuntime(6982): FATAL EXCEPTION: main
11-19 19:52:42.735: E/AndroidRuntime(6982): android.database.sqlite.SQLiteException: attempt to write a readonly database: UPDATE ANSWERS SET showhint1=1 WHERE QUESTION_ID=18 AND LEVEL =1 AND PLAYER='trst'
11-19 19:52:42.735: E/AndroidRuntime(6982):     at android.database.sqlite.SQLiteDatabase.native_execSQL(Native Method)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1763)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at com.test.game.db.DataBaseHelper.insertString(DataBaseHelper.java:301)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at com.test.game.Answer.onClick(Answer.java:241)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at android.view.View.performClick(View.java:2491)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at android.view.View$PerformClick.run(View.java:9086)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at android.os.Handler.handleCallback(Handler.java:587)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at android.os.Handler.dispatchMessage(Handler.java:92)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at android.os.Looper.loop(Looper.java:130)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at android.app.ActivityThread.main(ActivityThread.java:3683)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at java.lang.reflect.Method.invokeNative(Native Method)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at java.lang.reflect.Method.invoke(Method.java:507)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:861)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:619)
11-19 19:52:42.735: E/AndroidRuntime(6982):     at dalvik.system.NativeStart.main(Native Method)
4

3 回答 3

3 
Cursor c = myDataBase.rawQuery(
        "SELECT * FROM ANSWERS WHERE QUESTION_ID=" + id
                + " AND PLAYER ='" + player + "'", null);

//Try adding this
myDatabase.close();

myDataBase = this.getWritableDatabase();

编辑：尝试进行如下更改：

myDatabase.close();
myDataBase = this.getWritableDatabase();
Cursor c = myDataBase.rawQuery(
        "SELECT * FROM ANSWERS WHERE QUESTION_ID=" + id
                + " AND PLAYER ='" + player + "'", null);

//move this to before the rawQuery
//myDataBase = this.getWritableDatabase();
于 2012-11-19T18:40:11.723 回答
2

显然，您在多个位置打开数据库：

// myDataBase is already open or else this could not work
Cursor c = myDataBase.rawQuery(
        "SELECT * FROM ANSWERS WHERE QUESTION_ID=" + id
                + " AND PLAYER ='" + player + "'", null);

// You are opening myDataBase again
myDataBase = this.getWritableDatabase();

只需通过您的代码查找getWritableDatabase()并getReadableDatabase()找到您忘记关闭它的任何位置。或者，如果您经常访问数据库，请在 Activity 中打开数据库一次，onResume()然后在onPause().

于 2012-11-19T18:10:01.463 回答
0

这与其说是一个黑客的答案。但是您可以尝试在数据库助手类的 openDatabase 方法中关闭数据库。像下面这样的东西可能会起作用。

    if (this.db.isOpen()) {
       this.db.close();
    }
于 2012-11-19T17:57:47.220 回答