Android Widget - update when a button is clicked

Question

Good day. I'm trying to create a widget that will show the balance on the screen. Created 2 buttons and set up the listener to determine which button was pressed.

Difficulty: How to update data by clicking on the button or reload the widget so that the data is updated?

import android.app.AlarmManager;
import android.app.PendingIntent;
import android.appwidget.AppWidgetManager;
import android.appwidget.AppWidgetProvider;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.util.Log;
import android.widget.RemoteViews;
import android.widget.Toast;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.text.DateFormat;
import java.util.Date;

public class EthWidgetProvider extends AppWidgetProvider {
    private static final String SYNC_CLICKED    = "automaticWidgetSyncButtonClick";
    private static final String SYNC_CLICKED2    = "automaticWidgetSyncButtonClick2";


    static void updateAppWidget(final Context context, final AppWidgetManager appWidgetManager, final int appWidgetId) {
        RequestSingleton.getInstance(context).fetchData(new VolleyCallback() {
            @Override
            public void onSuccessRequest(JSONArray result) {
                Log.i("Response", result.toString());
                String price = "";
                try {
                    JSONObject etherObject = result.getJSONObject(0);
                    price = etherObject.getString("price_usd");
                } catch (JSONException e) {
                    Log.e("JSONException", e.toString());
                }
                Log.i("Price", price);
                RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.example_widget);
                views.setTextViewText(R.id.gprs, "$" + price);

                String currentDateTimeString = DateFormat.getDateTimeInstance().format(new Date());
                views.setTextViewText(R.id.timeofday, currentDateTimeString);

                appWidgetManager.updateAppWidget(appWidgetId, views);
            }
        });
    }
    @Override
    public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {


        RemoteViews remoteViews;
        ComponentName watchWidget;

        remoteViews = new RemoteViews(context.getPackageName(), R.layout.example_widget);
        watchWidget = new ComponentName(context, EthWidgetProvider.class);

        remoteViews.setOnClickPendingIntent(R.id.refresh, getPendingSelfIntent(context, SYNC_CLICKED));
        remoteViews.setOnClickPendingIntent(R.id.example_widget_button, getPendingSelfIntent(context, SYNC_CLICKED2));
        appWidgetManager.updateAppWidget(watchWidget, remoteViews);

        for(int appId : appWidgetIds) {
            updateAppWidget(context, appWidgetManager, appId);
        }
    }

    @Override
    public void onReceive(Context context, Intent intent) {
        // TODO Auto-generated method stub
        super.onReceive(context, intent);

        if (SYNC_CLICKED.equals(intent.getAction())) {

            AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);

            RemoteViews remoteViews;
            ComponentName watchWidget;

            remoteViews = new RemoteViews(context.getPackageName(), R.layout.example_widget);
            watchWidget = new ComponentName(context, EthWidgetProvider.class);

            remoteViews.setTextViewText(R.id.timeofday, "TESTING");

            appWidgetManager.updateAppWidget(watchWidget, remoteViews);

        }

        if (SYNC_CLICKED2.equals(intent.getAction())) {

            AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);

            RemoteViews remoteViews;
            ComponentName watchWidget;

            remoteViews = new RemoteViews(context.getPackageName(), R.layout.example_widget);
            watchWidget = new ComponentName(context, EthWidgetProvider.class);

            remoteViews.setTextViewText(R.id.timeofday, "TESTING2");

            appWidgetManager.updateAppWidget(watchWidget, remoteViews);

        }
    }

protected PendingIntent getPendingSelfIntent(Context context, String action) {
        Intent intent = new Intent(context, getClass());
        intent.setAction(action);
        return PendingIntent.getBroadcast(context, 0, intent, 0);
    }
}

By pressing button 1, I need to show the activity. By pressing the second button, you need to update the widget so that the data is updated, that is, so that the request to the server goes again and the data is updated.

Any help would be appreciated.

Check my solution to a related issue [here](https://stackoverflow.com/a/75645961/2408879) — makata, Mar 05 '23 at 23:25

score 2 · Answer 1 · answered Nov 01 '19 at 13:13

2

I don't get you idea with the Broadcast.

The broadcast should not be inner class
Broadcast should extend BroadcastReceiver class
Broadcast should be defined in manifest

So when you do this, your receiver should be called after buttons are clicked.

But, you want something to wake up your Widget. And then Widget#onUpdate will fetch the updated data (that you download on widget click) and show them. To request update of your widget, you can use something like this:

public static void updateAppWidget(@NonNull Context applicationContext,
        @NonNull Class<? extends AppWidgetProvider> widgetProviderClass) {
    final ComponentName component = new ComponentName(applicationContext, widgetProviderClass);
    final int[] widgetIds;
    try {
        widgetIds = AppWidgetManager.getInstance(applicationContext).getAppWidgetIds(component);
    } catch (RuntimeException re) {
        Log.d(re, "Unable to obtain widget IDs.");
        return;
    }

    if (widgetIds.length == 0) {
        Log.d("There is no widget to be updated.");
        return;
    }

    final Intent intent = new Intent(applicationContext, widgetProviderClass);
    intent.setAction(AppWidgetManager.ACTION_APPWIDGET_UPDATE);
    intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_IDS, widgetIds);

    applicationContext.sendBroadcast(intent);
}

So to sum it up:

In widget setup views, listeners, and populate with last known data.
In listener broadcast either open Activity, or run some download
Don't forget BroadcastReceivers are running on UI thread; use goAsync() approach.
The downloaded data should be stored to some place, where widget can obtain them
call mentioned function to trigger widget update.

I believe, this is a quite specific and complex topic unlike the rest of Android, so feel free to ask anything I might missed :)

answered Nov 01 '19 at 13:13

l0v3

963
7
26

My goal is to create a widget that will show the balance from a specific resource. The widget at startup send a request and show the received response. There will be a button in the widget that should update the data by sending a request to the server. I wrote this code based on video lessons and records that I found on the network. If you help me with this, I will be very grateful. – Ahmadjoni Muhamad Nov 01 '19 at 13:57
@AhmadjoniMuhamad I would say, this is conceptually wrong idea. Widget's are very sensitive thing. And the update button is kinda anti pattern of widget usage. While the constant update is also wrong. So as for me, I would recommend you to use SyncAdapter, some persistent storage and through widget just fetch the data from the storage and show them. You can then omit the button completely. see: https://developer.android.com/training/sync-adapters/creating-sync-adapter – l0v3 Nov 01 '19 at 14:08
To avoid stress on the server, I decided to make a manual update of data at the right time to the user. Can you help me with this? – Ahmadjoni Muhamad Nov 01 '19 at 14:11
So instead of server you will transfer the balance to the user? Why you even creating widget? The app that syncs with the server on open will serve the same purpose. And it will also require one click from the user. But it won't have any battery impact on user. The widget's are usually made for quick action or as preview without any action needed. – l0v3 Nov 01 '19 at 14:16
In order to balance was always on the screen, I decided to create a widget. I so understand you have experience in creating widgets and work their on networks, help if not it is difficult. Do not think that it is right or not. Just help, I will be very happy for your help – Ahmadjoni Muhamad Nov 01 '19 at 14:27
Sorry friend, this is your fight. I can only lead you. But I cannot point you on something that is against guidelines as nobody writes about that. It was not about to judge. But anyway, I believe, everything you need is in my first answer, it's up to you if you can use it. Btw, you didn't say, where is the problem. The listener is not called, or what? – l0v3 Nov 01 '19 at 14:37
I will not say, this is my fight! “My fight may become your battle tomorrow” - Zamir Greziev – Ahmadjoni Muhamad Nov 01 '19 at 14:41

score 1 · Answer 2 · answered Aug 30 '20 at 22:03

There is a very helpful must-read official guide titled "Build an App Widget": (https://developer.android.com/guide/topics/appwidgets)

Please read this page carefully so you understand the concepts and focus on the AppWidgetProvider section for your problem. Although in this section, they use: PendingIntent.getActivity(), you are supposed to use a Service as PendingIntent.getService() to have your Service called on button click, and then have the Service update your Widget.

Basically you'll see that you need to:

Create a Service

Create a PendingIntent:

Intent intent = new Intent(context, YourService.class);
PendingIntent pendingIntent = PendingIntent.getService(context, 0, intent, 0);

Set the onClickPendingIntent listener on your RemoteViews object like this:
```
views.setOnClickPendingIntent(R.id.button, pendingIntent);
```

score 0 · Answer 3 · answered Nov 01 '19 at 13:22

0

To call activity:

remoteViews.setOnClickPendingIntent( R.id.button1, PendingIntent.getActivity(context, 0, new Intent( context, Main.class), 0) );

To update widgets from another class :

AppWidgetManager appWidgetManager = AppWidgetManager.getInstance( context );
int ids[] = appWidgetManager.getAppWidgetIds( componentName );
for( int id : ids ){
    //update textView here
    appWidgetManager.updateAppWidget( id, views);
}

answered Nov 01 '19 at 13:22

Style-7

985
12
27

Thanks for the answer. I need to update the widget not from another class, but by clicking on the button in the widget itself. What to do in this case? Your code did not work in my case – Ahmadjoni Muhamad Nov 01 '19 at 13:52
This is easy: you can call a service to update widgets. Then use PendingIntent.getService() – Style-7 Nov 01 '19 at 13:58
I tried to do this but could not, can I send you my project code so that you look once? – Ahmadjoni Muhamad Nov 01 '19 at 14:14

Android Widget - update when a button is clicked

3 Answers3