Question

所以我犯了一个大错误，在Android 4.0 +上测试我的代码，并认为它可以在其他版本上正常工作。但我面临的问题是2.X和3.X与SQLiteOpenHelper。

首先是代码：

 public class HelperDB extends SQLiteOpenHelper implements BaseColumns {

 public static final int DATABASE_VERSION = 2;
 public static final String DATABASE_NAME = "MYDB.db";
 public static final String TABLE_NAME = "MYtable";
 public static final String TABLE_NAME_LOGO = "MYLogos";
 public static final String COLUMN_NAME_1 = "xxxxx";
 public static final String COLUMN_NAME_2 = "yyyy";
 public static final String COLUMN_NAME_3 = "zzzz";
 public static final String COLUMN_NAME_4 = "aaaa";
 public static final String COLUMN_NAME_LOGO = "logo";
 public static final String COLUMN_NAME_5 = "3333";
 public static final String COLUMN_NAME_6 = "fffff";
 public static final String COLUMN_NAME_7= "Abc";

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

@Override
 public void onCreate(SQLiteDatabase db){

    db.execSQL("CREATE TABLE " + TABLE_NAME + "(" + _ID + " INTEGER PRIMARY KEY autoincrement," + COLUMN_NAME_1 + " TEXT not null," + COLUMN_NAME_2
            + " TEXT not null," + COLUMN_NAME_3 + " TEXT not null," + COLUMN_NAME_4 + " LONG not null," + COLUMN_NAME_5 + " INT DEFAULT 99," + COLUMN_NAME_6 +" INT DEFAULT 99);");


    db.execSQL("CREATE TABLE " + TABLE_NAME_LOGO + "(" + _ID + " INTEGER PRIMARY KEY autoincrement," + COLUMN_NAME_6 + " TEXT not null,"  +  COLUMN_NAME_7 + " INTERGET not null);");

}

      @Override
   public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

}

 }
******************************************************************************

  public class MatchesDB {

private HelperDB dbHelper;  
private SQLiteDatabase dbw, dbr; 
public static int id;

public MatchesDB(Context context){  

    dbHelper = new HelperDB(context); 
    dbw = dbHelper.getWritableDatabase();
    dbr = dbHelper.getReadableDatabase();
}

public void fillinfotable(){}
And all other functions to query the database and delete etc

通过调用

创建数据库

      MatchesDB newdb = new MatchesDB(context);
  newdb.fillinfotable();

所有这一切都适用于所有4.0 +设备。但是，当我尝试在2.x设备上运行时，我收到以下错误

07-14 21:29:14.890: E/Database(22231): CREATE TABLE android_metadata failed
07-14 21:29:14.898: E/Database(22231): CREATE TABLE android_metadata failed
07-14 21:29:15.640: E/Database(22231): Failed to setLocale() when constructing, closing      the database
07-14 21:29:15.640: E/Database(22231): android.database.sqlite.SQLiteException:  database is locked
07-14 21:29:15.640: E/Database(22231):  at android.database.sqlite.SQLiteDatabase.native_setLocale(Native Method)
07-14 21:29:15.640: E/Database(22231):  at   android.database.sqlite.SQLiteDatabase.setLocale(SQLiteDatabase.java:2000)
07-14 21:29:15.640: E/Database(22231):  at android.database.sqlite.SQLiteDatabase. <init>(SQLiteDatabase.java:1857)
07-14 21:29:15.640: E/Database(22231):  at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:822)
07-14 21:29:15.640: E/Database(22231):  at android.database.sqlite.SQLiteDatabase.openOrCreateDatabase(SQLiteDatabase.java:856)
07-14 21:29:15.640: E/Database(22231):  at android.database.sqlite.SQLiteDatabase.openOrCreateDatabase(SQLiteDatabase.java:849)
07-14 21:29:15.640: E/Database(22231):  at android.app.ContextImpl.openOrCreateDatabase(ContextImpl.java:556)
07-14 21:29:15.640: E/Database(22231):  at android.content.ContextWrapper.openOrCreateDatabase(ContextWrapper.java:203)
07-14 21:29:15.640: E/Database(22231):  at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:118)

任何帮助都非常感谢!!真的想快速解决，因为该应用已经在Play商店，我需要发布更新

Answer 1

不确定它是否是一种“最佳实践”，但在我的应用程序中，我从不保持数据库打开。我在几乎每个CRUD动作之前/之后打开和关闭它。它适用于Android 2.2。

Answer 2

问题是我使用asyntasks从一个小部件进行这些数据库操作。虽然这在Android 4.0 +设备上运行得很好，但是对于较小版本的android，我必须先创建一个活动，然后在应用程序中创建所有数据库并填充表格，然后让小部件检索并显示该数据。

在Android 2.X和3.X上使用SQLiteOpenHelper的问题

2 个答案: