RecomendationCardView ContentProvider Example

SampleRecommendationContentProvider

/**
 * The MIT License (MIT)
 * Copyright (c) 2014 David Carver
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS
 * OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package us.nineworlds.serenity.core;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLDecoder;

import us.nineworlds.serenity.SerenityApplication;
import android.content.ContentProvider;
import android.content.ContentValues;
import android.database.Cursor;
import android.net.Uri;
import android.os.ParcelFileDescriptor;
import android.util.Log;

import com.squareup.okhttp.OkHttpClient;

/**
 * Provides a background image for Recommendations for a RecommendationCardView.
 *
 * The card view changed to require a content provider be created. It requests
 * items via the openFile(Uri uri) method. This is an example of how to retrieve
 * an image from a web site and provide a ParcelFileDescriptor back that
 * contains the contents.
 *
 * This is based on code from the following stackoverflow description on how to
 * populate a ParcelFileDescriptor from any input stream.
 *
 * http://stackoverflow.com/a/14734310/1950264
 *
 * You still need to setup a ContentProvider entry and Authority in the
 * AndroidManifest.xml
 *
 * See
 * http://developer.android.com/reference/android/content/ContentProvider.html
 *
 */
public class SampleRecommendationContentProvider extends ContentProvider {

	public static String AUTHORITY = "your unique authority here";
	public static String CONTENT_URI = "content://" + AUTHORITY + "/";

	@Override
	public boolean onCreate() {
		return true;
	}

	@Override
	public ParcelFileDescriptor openFile(Uri uri, String mode)
			throws FileNotFoundException {
		ParcelFileDescriptor[] pipe = null;

		String url = uri.getPath();

		try {
			String decodedUrl = URLDecoder.decode(url.replaceFirst("/", ""),
					"UTF-8");
			pipe = ParcelFileDescriptor.createPipe();

			// This uses OKHttp to
			OkHttpClient httpClient = new OkHttpClient();
			HttpURLConnection connection = httpClient.open(new URL(decodedUrl));

			new TransferThread(connection.getInputStream(),
					new ParcelFileDescriptor.AutoCloseOutputStream(pipe[1]))
					.start();
		} catch (IOException e) {
			Log.e(getClass().getSimpleName(), "Exception opening pipe", e);
			throw new FileNotFoundException("Could not open pipe for: "
					+ uri.toString());
		}

		return (pipe[0]);
	}

	@Override
	public Cursor query(Uri uri, String[] projection, String selection,
			String[] selectionArgs, String sortOrder) {
		return null;
	}

	@Override
	public String getType(Uri uri) {
		return "image/*";
	}

	@Override
	public Uri insert(Uri uri, ContentValues values) {
		return null;
	}

	@Override
	public int delete(Uri uri, String selection, String[] selectionArgs) {
		return 0;
	}

	@Override
	public int update(Uri uri, ContentValues values, String selection,
			String[] selectionArgs) {
		return 0;
	}

	static class TransferThread extends Thread {
		InputStream in;
		OutputStream out;

		TransferThread(InputStream in, OutputStream out) {
			this.in = in;
			this.out = out;
		}

		@Override
		public void run() {
			byte[] buf = new byte[8192];
			int len;

			try {
				while ((len = in.read(buf)) > 0) {
					out.write(buf, 0, len);
				}

				in.close();
				out.flush();
				out.close();
			} catch (IOException e) {
				Log.e(getClass().getSimpleName(),
						"Exception transferring file", e);
			}
		}
	}

}