Android example source code file (WordWidget.java)

This example Android source code file (WordWidget.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

android, api, app, application, appwidgetmanager, componentname, content, couldn't, intent, matcher, override, pendingintent, regex, remoteviews, resources, string, time, widget, wordwidget, wotd_pattern

The WordWidget.java Android example source code

/*
 * Copyright (C) 2009 The Android Open Source Project
 *
 * 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.
 */

package com.example.android.wiktionary;

import com.example.android.wiktionary.SimpleWikiHelper.ApiException;
import com.example.android.wiktionary.SimpleWikiHelper.ParseException;

import android.app.PendingIntent;
import android.app.Service;
import android.appwidget.AppWidgetManager;
import android.appwidget.AppWidgetProvider;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.res.Resources;
import android.net.Uri;
import android.os.IBinder;
import android.text.format.Time;
import android.util.Log;
import android.widget.RemoteViews;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Define a simple widget that shows the Wiktionary "Word of the day." To build
 * an update we spawn a background {@link Service} to perform the API queries.
 */
public class WordWidget extends AppWidgetProvider {
    @Override
    public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
        // To prevent any ANR timeouts, we perform the update in a service
        context.startService(new Intent(context, UpdateService.class));
    }

    public static class UpdateService extends Service {
        @Override
        public void onStart(Intent intent, int startId) {
            // Build the widget update for today
            RemoteViews updateViews = buildUpdate(this);

            // Push update for this widget to the home screen
            ComponentName thisWidget = new ComponentName(this, WordWidget.class);
            AppWidgetManager manager = AppWidgetManager.getInstance(this);
            manager.updateAppWidget(thisWidget, updateViews);
        }

        @Override
        public IBinder onBind(Intent intent) {
            return null;
        }

        /**
         * Regular expression that splits "Word of the day" entry into word
         * name, word type, and the first description bullet point.
         */
        private static final String WOTD_PATTERN =
            "(?s)\\{\\{wotd\\|(.+?)\\|(.+?)\\|([^#\\|]+).*?\\}\\}";

        /**
         * Build a widget update to show the current Wiktionary
         * "Word of the day." Will block until the online API returns.
         */
        public RemoteViews buildUpdate(Context context) {
            // Pick out month names from resources
            Resources res = context.getResources();
            String[] monthNames = res.getStringArray(R.array.month_names);

            // Find current month and day
            Time today = new Time();
            today.setToNow();

            // Build the page title for today, such as "March 21"
            String pageName = res.getString(R.string.template_wotd_title,
                    monthNames[today.month], today.monthDay);
            String pageContent = null;

            try {
                // Try querying the Wiktionary API for today's word
                SimpleWikiHelper.prepareUserAgent(context);
                pageContent = SimpleWikiHelper.getPageContent(pageName, false);
            } catch (ApiException e) {
                Log.e("WordWidget", "Couldn't contact API", e);
            } catch (ParseException e) {
                Log.e("WordWidget", "Couldn't parse API response", e);
            }

            RemoteViews views = null;
            Matcher matcher = Pattern.compile(WOTD_PATTERN).matcher(pageContent);
            if (matcher.find()) {
                // Build an update that holds the updated widget contents
                views = new RemoteViews(context.getPackageName(), R.layout.widget_word);

                String wordTitle = matcher.group(1);
                views.setTextViewText(R.id.word_title, wordTitle);
                views.setTextViewText(R.id.word_type, matcher.group(2));
                views.setTextViewText(R.id.definition, matcher.group(3).trim());

                // When user clicks on widget, launch to Wiktionary definition page
                String definePage = String.format("%s://%s/%s", ExtendedWikiHelper.WIKI_AUTHORITY,
                        ExtendedWikiHelper.WIKI_LOOKUP_HOST, wordTitle);
                Intent defineIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(definePage));
                PendingIntent pendingIntent = PendingIntent.getActivity(context,
                        0 /* no requestCode */, defineIntent, 0 /* no flags */);
                views.setOnClickPendingIntent(R.id.widget, pendingIntent);

            } else {
                // Didn't find word of day, so show error message
                views = new RemoteViews(context.getPackageName(), R.layout.widget_message);
                views.setTextViewText(R.id.message, context.getString(R.string.widget_error));
            }
            return views;
        }
    }
}