Ormlite+RecyclerView

CursorRecyclerViewAdapter

/*
 * Copyright (C) 2014 [email protected]
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

import android.content.Context;
import android.database.Cursor;
import android.database.DataSetObserver;
import android.support.v7.widget.RecyclerView;

// Code from https://gist.github.com/skyfishjy/443b7448f59be978bc59
// Fix to remove observers (when using CursorLoaders) by: https://gist.github.com/quanturium/46541c81aae2a916e31d
public abstract class CursorRecyclerViewAdapter<VH extends RecyclerView.ViewHolder> extends RecyclerView.Adapter<VH> {

    private Cursor mCursor;
    private boolean mDataValid;
    private int mRowIdColumn;

    public CursorRecyclerViewAdapter(Cursor cursor) {
        mCursor = cursor;
        mDataValid = cursor != null;
        mRowIdColumn = mDataValid ? mCursor.getColumnIndexOrThrow("_id") : -1;
        setHasStableIds(true);
    }
    
    public Cursor getCursor() {
        return mCursor;
    }

    @Override
    public int getItemCount() {
        if (mDataValid && mCursor != null) {
            return mCursor.getCount();
        } else {
            return 0;
        }
    }

    @Override
    public long getItemId(int position) {
        if (hasStableIds() && mDataValid && mCursor != null) {
            if (mCursor.moveToPosition(position)) {
                return mCursor.getLong(mRowIdColumn);
            } else {
                return RecyclerView.NO_ID;
            }
        } else {
            return RecyclerView.NO_ID;
        }
    }

    public Object getItem(int position) {
        if (mDataValid && mCursor != null) {
            mCursor.moveToPosition(position);
            return mCursor;
        } else {
            return null;
        }
    }

    public abstract void onBindViewHolder(VH viewHolder, Cursor cursor);

    @Override
    public void onBindViewHolder(VH viewHolder, int position) {
        if (!mDataValid) {
            throw new IllegalStateException("this should only be called when the cursor is valid");
        }
        if (!mCursor.moveToPosition(position)) {
            throw new IllegalStateException("couldn't move cursor to position " + position);
        }
        onBindViewHolder(viewHolder, mCursor);
    }

    /**
     * Change the underlying cursor to a new cursor. If there is an existing cursor it will be
     * closed.
     */
    public void changeCursor(Cursor cursor) {
        Cursor old = swapCursor(cursor);
        if (old != null) {
            old.close();
        }
    }

    /**
     * Swap in a new Cursor, returning the old Cursor.  Unlike
     * {@link #changeCursor(Cursor)}, the returned old Cursor is <em>not</em>
     * closed.
     */
    public Cursor swapCursor(Cursor newCursor) {
        if (newCursor == mCursor) {
            return null;
        }
        final int oldCursorSize = getItemCount();
        final Cursor oldCursor = mCursor;
        mCursor = newCursor;
        if (mCursor != null) {
            mRowIdColumn = newCursor.getColumnIndexOrThrow("_id");
            mDataValid = true;
            notifyDataSetChanged();
        } else {
            mRowIdColumn = -1;
            mDataValid = false;
            // notify the observers about the lack of a data set
            notifyItemRangeRemoved(0, oldCursorSize);
        }
        return oldCursor;
    }
}

Implementation example

import android.content.Context;
import android.graphics.Typeface;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class DrawerRecyclerViewAdapter extends OrmliteCursorRecyclerViewAdapter<Championship, DrawerRecyclerViewAdapter.ViewHolder> {
    public DrawerRecyclerViewAdapter(Context context) {
        super(context);
    }

    @Override
    public DrawerRecyclerViewAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.drawer_row, parent, false);
        return new ViewHolder(v);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, Championship championship) {
        holder.drawerTextView.setText(championship.getCommonName());
    }

    public static class ViewHolder extends RecyclerView.ViewHolder {
        public final TextView drawerTextView;

        public ViewHolder(View drawerView) {
            super(drawerView);
            drawerTextView = (TextView) drawerView.findViewById(R.id.drawerTextView);
        }
    }
}

OrmliteCursorRecyclerViewAdapter

import android.content.Context;
import android.database.Cursor;
import android.support.v7.widget.RecyclerView;

import com.j256.ormlite.android.AndroidDatabaseResults;
import com.j256.ormlite.stmt.PreparedQuery;

import java.sql.SQLException;

// Based on https://github.com/j256/ormlite-android/pull/8
public abstract class OrmliteCursorRecyclerViewAdapter<T, VH extends RecyclerView.ViewHolder> extends CursorRecyclerViewAdapter<VH> {
    protected PreparedQuery<T> preparedQuery;

    public OrmliteCursorRecyclerViewAdapter(Context context){
        super(context,null);
    }

    public abstract void onBindViewHolder(VH holder, T t);

    public final void onBindViewHolder(VH viewHolder, Cursor cursor){
        try {
            onBindViewHolder(viewHolder, this.cursorToObject(cursor));
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    public final void changeCursor(Cursor cursor) {
        throw new UnsupportedOperationException("Please use OrmLiteCursorAdapter.changeCursor(Cursor,PreparedQuery) instead");
    }

    public void changeCursor(Cursor cursor, PreparedQuery<T> preparedQuery) {
        this.setPreparedQuery(preparedQuery);
        super.changeCursor(cursor);
    }

    public void setPreparedQuery(PreparedQuery<T> preparedQuery) {
        this.preparedQuery = preparedQuery;
    }

    public T getTypedItem(int position) {
        try {
            return this.cursorToObject((Cursor)getItem(position));
        } catch (SQLException var3) {
            throw new RuntimeException(var3);
        }
    }

    protected T cursorToObject(Cursor cursor) throws SQLException {
        return this.preparedQuery.mapRow(new AndroidDatabaseResults(cursor, null));
    }
}