使用AlarmManager更新应用小部件

时间:2011-03-29 18:00:44

标签: android android-widget alarmmanager

我试图比1.6docs施加的30分钟限制更频繁地更新Widget。在阅读了SO中的几乎所有帖子,以及开发人员文档和其他各种来源之后,我认为我已经达到了可以实现它的程度。所以,我尝试过,但失败了。从那时起,我已经搜索了更多的论坛和解决方案,我似乎无法更新它。

我有一个设置AlarmManager的Update类:

public class Update extends Service{

    @Override
    public void onStart(Intent intent, int startId) {
          String currentTemp = Battery.outputTemp;
          String currentLevel = Battery.outputLevel;
          String currentCard = Battery.outputCard;
          String currentInternal = Battery.memory;
          String currentRam = String.valueOf(Battery.outputRam).substring(0, 3) + "MB";

          // Change the text in the widget
          RemoteViews updateViews = new RemoteViews( 
          this.getPackageName(), R.layout.main);
          //update temp
          updateViews.setTextViewText(R.id.batteryTemp, currentTemp); 
          //update %
          updateViews.setTextViewText(R.id.batteryLevel, currentLevel);     
          //update level
          updateViews.setTextViewText(R.id.sdCard, currentCard);
          //update internal memory
          updateViews.setTextViewText(R.id.internal, currentInternal);
          //update ram
          updateViews.setTextViewText(R.id.ram, currentRam);

          ComponentName thisWidget = new ComponentName(this, Widget.class);
          AppWidgetManager manager = AppWidgetManager.getInstance(this);
          manager.updateAppWidget(thisWidget, updateViews);

    }
    @Override
    public IBinder onBind(Intent intent) {
        // no need to bind
        return null;
    }

}

这导致我的widget类中的onReceive经常触发(我有一个Toast来查看它何时触发),但它没有任何意图(toast意味着显示它,因为它们被收到但是它是空白的)。

我无法弄明白(我是一个相对较新的2个月的慢速Android开发者),并欣赏你们有任何洞察力。

继承我的widget类供参考:

    public class Widget extends AppWidgetProvider {


    @Override
    public void onUpdate(Context context, AppWidgetManager appWidgetManager,
            int[] appWidgetIds) {

        AlarmManager alarmManager;
        Intent intent = new Intent(context, Update.class);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 0,
                intent, PendingIntent.FLAG_UPDATE_CURRENT);
        alarmManager = (AlarmManager) context
                .getSystemService(Context.ALARM_SERVICE);
        Calendar cal = Calendar.getInstance();
        cal.setTimeInMillis(System.currentTimeMillis());
        cal.add(Calendar.SECOND, 10);
        alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, cal
                .getTimeInMillis(), 5 * 1000, pendingIntent);

        String currentTemp = Battery.outputTemp;
        String currentLevel = Battery.outputLevel;
        String currentCard = Battery.outputCard;
        String currentInternal = Battery.memory;
        String currentRam = String.valueOf(Battery.outputRam).substring(0, 3)
                + "MB";

        // Change the text in the widget
        RemoteViews updateViews = new RemoteViews(context.getPackageName(),
                R.layout.main);
        // update temp
        updateViews.setTextViewText(R.id.batteryTemp, currentTemp);
        appWidgetManager.updateAppWidget(appWidgetIds, updateViews);
        // update %
        updateViews.setTextViewText(R.id.batteryLevel, currentLevel);
        appWidgetManager.updateAppWidget(appWidgetIds, updateViews);
        // update level
        updateViews.setTextViewText(R.id.sdCard, currentCard);
        appWidgetManager.updateAppWidget(appWidgetIds, updateViews);
        // update internal memory
        updateViews.setTextViewText(R.id.internal, currentInternal);
        appWidgetManager.updateAppWidget(appWidgetIds, updateViews);
        // update ram
        updateViews.setTextViewText(R.id.ram, currentRam);
        appWidgetManager.updateAppWidget(appWidgetIds, updateViews);
        super.onUpdate(context, appWidgetManager, appWidgetIds);

    }

    public void onReceive(Context context, Intent intent) {

        super.onReceive(context, intent);
        Toast
                .makeText(context, intent.getAction() + context,
                        Toast.LENGTH_LONG).show();
        Bundle extras = intent.getExtras();
        if (extras != null) {
            AppWidgetManager appWidgetManager = AppWidgetManager
                    .getInstance(context);
            ComponentName thisAppWidget = new ComponentName(context
                    .getPackageName(), Widget.class.getName());
            int[] appWidgetIds = appWidgetManager
                    .getAppWidgetIds(thisAppWidget);

            onUpdate(context, appWidgetManager, appWidgetIds);
        }

    }
}

4 个答案:

答案 0 :(得分:20)

这是我的解决方案,如何比30分钟更频繁地自动更新小部件。我使用AlarmManager。在使用AlarmManager刷新appwidget之前,请确保您知道自己在做什么,因为这种技术可能会耗尽设备的电量。

详细了解Android文档中的widget update - 尤其是有关updatePeriodMillis参数的内容。

这是我的Manifest.xml的一部分。我定义自定义操作AUTO_UPDATE。

<receiver android:name=".appwidget.AppWidget" >
    <intent-filter>
        <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
    </intent-filter>
    <intent-filter>
        <action android:name="AUTO_UPDATE" />
    </intent-filter>
    <meta-data android:name="android.appwidget.provider" android:resource="@xml/appwidget_info" />
</receiver>

这是我的AppWidget.java的一部分。在onReceive方法中,我处理自定义操作AUTO_UPDATE。在onEnabled和onDisabled方法中,我启动/停止警报。

public class AppWidget extends AppWidgetProvider
{
    public static final String ACTION_AUTO_UPDATE = "AUTO_UPDATE";

    @Override
    public void onReceive(Context context, Intent intent)
    {
        super.onReceive(context, intent);

        if(intent.getAction().equals(ACTION_AUTO_UPDATE))
        {
            // DO SOMETHING
        }

        ...
    }

    @Override
    public void onEnabled(Context context)
    {
        // start alarm
        AppWidgetAlarm appWidgetAlarm = new AppWidgetAlarm(context.getApplicationContext());
        appWidgetAlarm.startAlarm();
    }

    @Override
    public void onDisabled(Context context)
    {
        // stop alarm only if all widgets have been disabled
        AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
        ComponentName thisAppWidgetComponentName = new ComponentName(context.getPackageName(),getClass().getName());
        int[] appWidgetIds = appWidgetManager.getAppWidgetIds(thisAppWidgetComponentName);
        if (appWidgetIds.length == 0) {
            // stop alarm
            AppWidgetAlarm appWidgetAlarm = new AppWidgetAlarm(context.getApplicationContext());
            appWidgetAlarm.stopAlarm();
    }

    }

    ...
}

这是我的AppWidgetAlarm.java,它启动/停止警报。警报管理器向AppWidget发送广播。

public class AppWidgetAlarm
{
    private final int ALARM_ID = 0;
    private final int INTERVAL_MILLIS = 10000;

    private Context mContext;


    public AppWidgetAlarm(Context context)
    {
        mContext = context;
    }


    public void startAlarm()
    {
        Calendar calendar = Calendar.getInstance();
        calendar.add(Calendar.MILLISECOND, INTERVAL_MILLIS);

        Intent alarmIntent = new Intent(AppWidget.ACTION_AUTO_UPDATE);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(mContext, ALARM_ID, alarmIntent, PendingIntent.FLAG_CANCEL_CURRENT);

        AlarmManager alarmManager = (AlarmManager) mContext.getSystemService(Context.ALARM_SERVICE);
        // RTC does not wake the device up
        alarmManager.setRepeating(AlarmManager.RTC, calendar.getTimeInMillis(), INTERVAL_MILLIS, pendingIntent);
    }


    public void stopAlarm()
    {
        Intent alarmIntent = new Intent(AppWidget.ACTION_AUTO_UPDATE);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(mContext, ALARM_ID, alarmIntent, PendingIntent.FLAG_CANCEL_CURRENT);

        AlarmManager alarmManager = (AlarmManager) mContext.getSystemService(Context.ALARM_SERVICE);
        alarmManager.cancel(pendingIntent);
    }
}

答案 1 :(得分:12)

  

我有一个设置AlarmManager的Update类:

不,你没有。 <{1}}无法在代码段中显示。

在第二个代码段中引用了AlarmManager。那里的问题包括:

  • 每次应用小部件更新

  • 时,您都会设置新的重复闹钟
  • 你在警报上设置了5秒的频率,这完全疯了

  • 您在AlarmManager警报上设置了5秒的频率,我认为这是您在某些司法管辖区被捕的理由

  • 你有一个毫无意义的_WAKEUP方法,甚至忽略了临时onReceive()

  • 您假设Toast中的Intent上会有一个操作字符串,但您在创建Toast时未指定操作字符串放入Intent进行警报

  • 你的代码指的是我认为PendingIntent类上的静态数据成员,但很可能那些都是空的/ null ...或者至少它们会是,如果你有报警上的一个合理的频率

答案 2 :(得分:1)

感谢本示例-使用更高版本的Android版本也遇到了问题。

这篇文章对我有用: widget case that doesn't work(请参阅Larry Schiefer的回答)。

因此,请用上面的代码代替它:

Intent alarmIntent = new Intent(AppWidget.ACTION_AUTO_UPDATE);
PendingIntent pendingIntent = PendingIntent.getBroadcast(mContext, ALARM_ID, alarmIntent, PendingIntent.FLAG_CANCEL_CURRENT);

与此相关:

Intent alarmIntent=new Intent(mContext, MyWidget.class);
alarmIntent.setAction(AppWidget.ACTION_AUTO_UPDATE);
PendingIntent pendingIntent = PendingIntent.getBroadcast(mContext, ALARM_ID, alarmIntent, PendingIntent.FLAG_CANCEL_CURRENT);

工作完成了。

答案 3 :(得分:1)

petrnohejl解决方案的一些修改版本。这个正在我的项目中工作。 (用kotlin编写):

这是Manifest.xml的一部分。我添加了以下操作:AUTO_UPDATE,APPWIDGET_UPDATE,APPWIDGET_ENABLED,APWIDGET_DISABLED。

                <receiver android:name=".AppWidget">
                    <intent-filter>
                        <action android:name="android.appwidget.action.APPWIDGET_UPDATE"/>
                        <action android:name="android.appwidget.action.APPWIDGET_ENABLED" />
                        <action android:name="android.appwidget.action.APPWIDGET_DISABLED"/>
                    </intent-filter>
                    <intent-filter>
                        <action android:name="ACTION_AUTO_UPDATE" />
                    </intent-filter>

                    <meta-data
                            android:name="android.appwidget.provider"
                            android:resource="@xml/appwidget_info"/>
                </receiver>

这是AppWidget.kt的一部分。在这里,我实现了onUpdate(),onEnabled(),onDisabled(),onReceive()函数。

class AppWidget: AppWidgetProvider() {

    override fun onUpdate(context: Context, appWidgetManager: AppWidgetManager, appWidgetIds: IntArray) {

        // There may be multiple widgets active, so update all of them
        for (appWidgetId in appWidgetIds) {
            updateAppWidget(context, appWidgetManager, appWidgetId)
        }
    }

    override fun onEnabled(context: Context) { // Enter relevant functionality for when the first widget is created

        // start alarm
        val appWidgetAlarm = AppWidgetAlarm(context.applicationContext)
        appWidgetAlarm.startAlarm()
    }

    override fun onDisabled(context: Context) { // Enter relevant functionality for when the last widget is disabled

        // stop alarm only if all widgets have been disabled
        val appWidgetManager = AppWidgetManager.getInstance(context)

        if (appWidgetIds.isEmpty()) {
            // stop alarm
            val appWidgetAlarm = AppWidgetAlarm(context.getApplicationContext())
            appWidgetAlarm.stopAlarm()
        }
    }

    companion object {

        val ACTION_AUTO_UPDATE = "AUTO_UPDATE"

        fun updateAppWidget(context: Context, appWidgetManager: AppWidgetManager, appWidgetId: Int) {

        val widgetText = Random.nextInt(0, 100).toString()

            // Construct the RemoteViews object
            val views = RemoteViews(context.packageName, R.layout.appwidget)
            views.setTextViewText(R.id.widget_text, widgetText)

            // Instruct the widget manager to update the widget
            appWidgetManager.notifyAppWidgetViewDataChanged(appWidgetId, R.id.widget_text)
            appWidgetManager.updateAppWidget(appWidgetId, views)
        }
    }

    override fun onReceive(context: Context?, intent: Intent?) {
        super.onReceive(context, intent)

        // Do something

        /*if (intent!!.action == ACTION_AUTO_UPDATE) {
            // DO SOMETHING
        }*/
    }
}

这是AppWidgetAlarm.kt。这是我的主要修改。答案并没有帮助我,但正在起作用。我在这里设置了重复警报。 (https://developer.android.com/training/scheduling/alarms

class AppWidgetAlarm(private val context: Context?) {
        private val ALARM_ID = 0
        private val INTERVAL_MILLIS : Long = 10000

    fun startAlarm() {
        val calendar: Calendar = Calendar.getInstance()
        calendar.add(Calendar.MILLISECOND, INTERVAL_MILLIS.toInt())        

        val alarmIntent = Intent(context, AppWidget::class.java).let { intent ->
            //intent.action = AppWidget.ACTION_AUTO_UPDATE
            PendingIntent.getBroadcast(context, 0, intent, 0)
        }
        with(context!!.getSystemService(Context.ALARM_SERVICE) as AlarmManager) {
           setRepeating(AlarmManager.RTC,calendar.timeInMillis, INTERVAL_MILLIS ,alarmIntent)
        }
    }

    fun stopAlarm() {
        val alarmIntent = Intent(AppWidget.ACTION_AUTO_UPDATE)
        val pendingIntent = PendingIntent.getBroadcast(context, ALARM_ID, alarmIntent, PendingIntent.FLAG_CANCEL_CURRENT)
        val alarmManager = context!!.getSystemService(Context.ALARM_SERVICE) as AlarmManager
        alarmManager.cancel(pendingIntent)
    }
}