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重写DaoMaster类中的OpenHelper 和DevOpenHelper 类中的方法
public static abstract class OpenHelper extends SQLiteOpenHelper {
public OpenHelper(Context context, String name, CursorFactory factory) {
//super(context, name, factory, SCHEMA_VERSION);
super(new ContextWrapper(context) {
/**
* 获得数据库路径,如果不存在,则创建对象对象
*
* @param name
*/
@Override
public File getDatabasePath(String name) {
// 判断是否存在sd卡
boolean sdExist = android.os.Environment.MEDIA_MOUNTED.equals(android.os.Environment.getExternalStorageState());
if (!sdExist) {// 如果不存在,
Log.e("SD卡管理:", "SD卡不存在,请加载SD卡");
return null;
} else {// 如果存在
// 获取sd卡路径
String dbMainDir = Constants.DATABASE_DIR;
String dbPath = dbMainDir + name;// 数据库路径
String dpdir = dbPath.substring(0, dbPath.lastIndexOf(File.separator));
Debug.e(" dbPath 数据库 dpdir " + dpdir + " dbPath:" + dbPath);
// 判断目录是否存在,不存在则创建该目录
File dirFile = new File(dpdir);
if (!dirFile.exists()) {
boolean dir = dirFile.mkdirs();
Debug.e(" 数据库目录创建失败 " + dir + " dbPath:" + dbPath);
}
// 数据库文件是否创建成功
boolean isFileCreateSuccess = false;
// 判断文件是否存在,不存在则创建该文件
File dbFile = new File(dbPath);
if (!dbFile.exists()) {
try {
isFileCreateSuccess = dbFile.createNewFile();// 创建文件
} catch (IOException e) {
e.printStackTrace();
Debug.e("数据库创建失败 " + e.toString());
}
} else {
isFileCreateSuccess = true;
}
Debug.e(" 返回数据库文件对象 " + isFileCreateSuccess);
// 返回数据库文件对象
if (isFileCreateSuccess)
return dbFile;
else
return super.getDatabasePath(name);
}
}
/**
* 重载这个方法,是用来打开SD卡上的数据库的,android 2.3及以下会调用这个方法。
*
* @param name
* @param mode
* @param factory
*/
@Override
public SQLiteDatabase openOrCreateDatabase(String name, int mode, CursorFactory factory) {
return SQLiteDatabase.openOrCreateDatabase(getDatabasePath(name), null);
}
/**
* Android 4.0会调用此方法获取数据库。
*
* @see ContextWrapper#openOrCreateDatabase(String,
* int,
* CursorFactory,
* DatabaseErrorHandler)
* @param name
* @param mode
* @param factory
* @param errorHandler
*/
@Override
public SQLiteDatabase openOrCreateDatabase(String name, int mode, CursorFactory factory, DatabaseErrorHandler errorHandler) {
return SQLiteDatabase.openOrCreateDatabase(getDatabasePath(name), null);
}
}, name, factory, SCHEMA_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
Log.i("greenDAO", "Creating tables for schema version " + SCHEMA_VERSION);
createAllTables(db, false);
}
}
/* WARNING: Drops all table on Upgrade! Use only during development. */
public static class DevOpenHelper extends OpenHelper {
public DevOpenHelper(Context context, String name, CursorFactory factory) {
super(context, name, factory);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.i("greenDAO", "Upgrading schema from version " + oldVersion + " to " + newVersion + " by dropping all tables");
dropAllTables(db, true);
onCreate(db);
}
}