PowerWidget.java

/*
Copyright (C) 2011 The University of Michigan

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.

Please send inquiries to powertutor@umich.edu
*/

package edu.umich.PowerTutor.widget;

import android.app.PendingIntent;
import android.appwidget.AppWidgetProvider;
import android.appwidget.AppWidgetManager;
import android.content.Context;
import android.content.ComponentName;
import android.content.Intent;
import android.content.SharedPreferences;
import android.preference.PreferenceManager;
import android.util.Log;
import android.widget.RemoteViews;

import edu.umich.PowerTutor.R;
import edu.umich.PowerTutor.service.PowerEstimator;
import edu.umich.PowerTutor.service.UMLoggerService;
import edu.umich.PowerTutor.ui.UMLogger;
import edu.umich.PowerTutor.util.Counter;
import edu.umich.PowerTutor.util.HexEncode;
import edu.umich.PowerTutor.util.SystemInfo;

import java.io.ByteArrayInputStream;
import java.io.ObjectInputStream;
import java.io.IOException;

public class PowerWidget extends AppWidgetProvider {
  private static final String TAG = "PowerWidget";

  private static final int[] text_ids = {
    R.id.text_minute,
    R.id.text_hour,
    R.id.text_day,
  };

  private static long sumArray(long[] A) {
    long ret = 0;
    for(long x : A) {
      ret += x;
    }
    return ret;
  }

  // Called once initially.
  public void onUpdate(Context context, AppWidgetManager appWidgetManager,
                       int[] appWidgetIds) {
    updateWidgetDone(context);
  }

  public void onDeleted(Context context, int[] appWidgetIds) {
    SharedPreferences.Editor edit =
            PreferenceManager.getDefaultSharedPreferences(context).edit();
    for(int id : appWidgetIds) {
      edit.remove("widget_" + id);
    }
    edit.commit();
  }

  public static void updateWidgetDone(Context context) {
    AppWidgetManager manager = AppWidgetManager.getInstance(context);
    ComponentName comp = new ComponentName(context, PowerWidget.class);
    RemoteViews views = new RemoteViews(context.getPackageName(),
                                        R.layout.widget_layout);

    Intent notificationIntent = new Intent(context, UMLogger.class);
    PendingIntent pendingIntent = PendingIntent.getActivity(context, 0,
                                                notificationIntent,
                            PendingIntent.FLAG_UPDATE_CURRENT);

    views.setOnClickPendingIntent(R.id.power_button, pendingIntent);
    views.setInt(R.id.power_button, "setImageResource",
                 R.drawable.power_off);
    for(int i = 0; i < text_ids.length; i++) {
      views.setTextViewText(text_ids[i], "N/A");
    }
    manager.updateAppWidget(comp, views);
  }

  // Called by the UMLogger Service every so often.
  public static void updateWidget(Context context, PowerEstimator p) {
    AppWidgetManager manager = AppWidgetManager.getInstance(context);
    ComponentName comp = new ComponentName(context, PowerWidget.class);

    for(int id : manager.getAppWidgetIds(comp)) {
      RemoteViews views = new RemoteViews(context.getPackageName(),
                                          R.layout.widget_layout);

      Intent notificationIntent = new Intent(context, UMLogger.class);
      notificationIntent.putExtra("isFromIcon", true);
      PendingIntent pendingIntent = PendingIntent.getActivity(context, 0,
                                                  notificationIntent,
                              PendingIntent.FLAG_UPDATE_CURRENT);

      views.setOnClickPendingIntent(R.id.power_button, pendingIntent);
      views.setInt(R.id.power_button, "setImageResource",
                   R.drawable.power_on);

      boolean ok = false;
      try {
        SharedPreferences prefs =
            PreferenceManager.getDefaultSharedPreferences(context);
        String key = "widget_" + id;
        String val = prefs.getString(key, null);
        if(val != null) {
          ObjectInputStream objin = new ObjectInputStream(
              new ByteArrayInputStream(HexEncode.decode(val)));
          for(int i = 0; i < text_ids.length; i++) {
            DataSource dataSource = (DataSource)objin.readObject();
            views.setTextViewText(text_ids[i], dataSource.getValue(p));
          }
          ok = true;
        } else {
          Log.w(TAG, "Could not find widget data source preference");
        }
      } catch(IOException e) {
        Log.w(TAG, "Failed to extract widget data sources");
      } catch(ClassCastException e) {
        Log.w(TAG, "Failed to extract widget data sources");
      } catch(ClassNotFoundException e) {
        Log.w(TAG, "Failed to extract widget data sources");
      }
      if(!ok) {
        for(int i =0; i < text_ids.length; i++) {
          views.setTextViewText(text_ids[i], "N/A");
        }
      }
      for(int i =0; i < text_ids.length; i++) {
        views.setTextColor(text_ids[i], 0xFFFFFFFF);
      }

      manager.updateAppWidget(id, views);
    }
  }
}