How to update an homescreen widget (the right way)

WidgetHelper.java

package net.frakbot.gists.widgethelper;

/*
 * Copyright 2014 Sebastiano Poggi
 *
 * 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.appwidget.AppWidgetManager;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;

/**
 * An helper class for handling homescreen widgets.
 * 
 * <b>NOTE:</b> this class assumes that you have an {@link android.appwidget.AppWidgetProvider}
 * named <code>WidgetProvider</code> (that handles widgets events).
 * In <code>WidgetProvider</code>, you have to define:
 * <code>public static final String EXTRA_WIDGET_IDS = "widget_ids";</code>
 * 
 * It would also be good practice to have widget updates happening in an
 * {@link android.app.IntentService} to avoid ANRs, as <code>AppWidgetProvider</code>
 * is a <code>BroadcastReceiver<code> and can't block the main thread for long.
 * You would then invoke this updater service from both the <code>WidgetProvider</code>
 * and from the {@link #updateAllHomescreenWidgets}. For the latter, you
 * simply have to change the <code>updateIntent</code> declaration to:
 * <code>Intent updateIntent = new Intent(c, <b>UpdaterService.class</b>);</code>
 */
public class WidgetHelper {

    /**
     * Updates all the homescreen widgets for this application.
     *
     * @param c The Context used to update the widgets.
     */
    public static void updateAllHomescreenWidgets(Context c) {
        AppWidgetManager widgetMgr = AppWidgetManager.getInstance(c);

        if (widgetMgr != null) {
            int[] widgetIds = widgetMgr.getAppWidgetIds(new ComponentName(c, WidgetProvider.class));

            Intent updateIntent = new Intent(c, WidgetProvider.class);
            updateIntent.setAction(AppWidgetManager.ACTION_APPWIDGET_UPDATE);
            updateIntent.putExtra(WidgetProvider.EXTRA_WIDGET_IDS, widgetIds);
            c.sendBroadcast(updateIntent);
        }
    }
}

Using the BroadcastReceiver / AppWidgetProvider when you're triggering the widget update yourself is a complete red herring. Just talk directly to the AppWidgetManager from a background thread (ideally wrapped via a Service).