AnKo SQLite : populate listview asynchronously from database?

Question

I'm trying to translate my app from Java to Kotlin. I'm managing database with AnKo SQLite

All is OK except listviews with CursorLoaders : I can't find how to replace CursorLoader while using AnKo SQLite. (and same problem with expandableListViews)

Can somebody help me please?

Answer 1

OK, here is my solution... I don't know if it is the best :

1. create a new kotlin class "MyCursorLoader" that extends CursorLoader

2. set the primary constructor like this :

   class MyCursorLoader( mContext: Context, val mTableName: String, var mProjection: Array<String>? = null, var mSelection: String = "1", var mSelectionArgs: Array<String> = emptyArray(), var mGroupBy: String = MySqlHelper.ID, var mHaving: String = "", var mSortOrder: String = "${MySqlHelper.ID} ASC", var mLimit: String = "", var mDistinct: Boolean = true ): CursorLoader(mContext) { val mObserver: Loader<Cursor>.ForceLoadContentObserver = Loader<Cursor>(mContext).ForceLoadContentObserver() var mCancellationSignal: CancellationSignal? = null

3. override the OnLoadInBackground method with te same code than built-in one, just replacing the val cursor = ContentResolverCompat.query(... line with :

   val cursor = MySqlHelper.instance.readableDatabase.query(
       mDistinct, mTableName, mProjection, mSelection, mSelectionArgs, mGroupBy, mHaving, mSortOrder, mLimit, mCancellationSignal)
   

So no need to recreate a dataprovider in manifest, no need to deal with Uri's... I can use MyCursorLoader exactly like built-in CursorLoader, calling it like this :

    override fun onCreateLoader(id: Int, args: Bundle?): Loader<Cursor> {
        when (id) {
            DAY_HEADER_LOADER ->
                return MyCursorLoader(mContext, TABLE_EVENTS, arrayOf(ID, DAY), mGroupBy = DAY, mSortOrder = "$DAY  DESC")
        ...
        }
    }

Let me know if ther is a better solution.

Hope that can help.