Android Cursor with ORMLite to use in CursorAdapte

2020-01-26 23:44发布

Is there any way, how to get Cursor for a query, which I am processing with ORMLite Dao object?

4条回答
乱世女痞
2楼-- · 2020-01-27 00:32

Did you try some of Gray's advice from this post? He explains how you can select a column as another name, such as, select id as _id.

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smile是对你的礼貌
3楼-- · 2020-01-27 00:33

ORMLite now supports next(), previous(), moveRelative(offset), ... methods on the CloseableIterator class. This should allow you to move the underlying Cursor object around at will.

It also supports the following DAO Cursor methods:


When you are building your own query with ORMLite, you use the QueryBuilder object. queryBuilder.prepare() returns a PreparedQuery which is used by various methods in the DAO. You can call dao.iterator(preparedQuery) which will return a CloseableIterator which is used to iterate through the results. There is a iterator.getRawResults() to get access to the DatabaseResults class. Under Android, this can be cast to an AndroidDatabaseResults which has a getCursor() method on it to return the Android Cursor.

Something like the following code:

// build your query
QueryBuilder<Foo, String> qb = fooDao.queryBuilder();
qb.where()...;
// when you are done, prepare your query and build an iterator
CloseableIterator<Foo> iterator = dao.iterator(qb.prepare());
try {
   // get the raw results which can be cast under Android
   AndroidDatabaseResults results =
       (AndroidDatabaseResults)iterator.getRawResults();
   Cursor cursor = results.getRawCursor();
   ...
} finally {
   iterator.closeQuietly();
}

This is a bit complicated but you are definitely having to peer behind the vale to get to this object which is hidden by the database abstraction classes.

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三岁会撩人
4楼-- · 2020-01-27 00:37

If you're in an Activity and don't want to mess around with the QueryBuilder give the following a go, which is just as effective.

Cursor cursor = getHelper().getReadableDatabase().query(tableName, projection, selection, selectionArgs, groupBy, having, sortOrder)
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不美不萌又怎样
5楼-- · 2020-01-27 00:45

If you mean the getHelper() method to reach the dao methods create etc. you only have to inherit from the OrmLiteBaseActivity<YourDBHelper> and you can call it. It will look sth like this:

public class YourClass extends OrmLiteBaseActivity<YourDBHelper> {
  @Override
  protected void onCreate(Bundle savedInstanceState) {
     ...
     getHelper().getDao().queryForAll();
     ...
  }
}

If you mean the cursor to handle database operation: I don't think that you can reach it! But I don't understand why you should need it. ORMLite has nearly all functions of the cursor. So what do you need it for?

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