How to implement a Button on an Android Widget

Question

I am just getting started with Android development and I have created a nice little widget that displays some info on my home screen. However, I now want to implement a Button on my widget that updates the info in my widget TextView.

Can anyone advise how to go about doing this?

Thanks

Answer 1

Solved - I can confirm that an Activity is NOT needed if you want create a Button to update an Android AppWidget.

I have been able to implement my AppWidgetProvider class such that it registers an android.appwidget.action.APPWIDGET_UPDATE intent-filter with the Broadcast receiver in the AndroidManifest.xml, which then fires the onUpdate event in the AppWidgetProvider class (which in turn then runs the UpdateService).

<!-- Broadcast Receiver that will process AppWidget updates -->
<receiver android:name=".MyWidget" android:label="@string/widget_name">
   <intent-filter>
      <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
   </intent-filter>
   <meta-data android:name="android.appwidget.provider" android:resource="@xml/widget" />
</receiver>

The UpdateService in my AppWidgetProvider class then uses onHandleIntent to run a private buildUpdate method - which registers the onClick event with a call to setOnClickPendingIntent as follows:

// set intent and register onclick
Intent i = new Intent(this, MyWidget.class);
PendingIntent pi = PendingIntent.getBroadcast(context,0, i,0);
updateViews.setOnClickPendingIntent(R.id.update_button,pi);

Here is a link to some source code of a working example, which shows how an update button can be used to update a Twitter widget:

https://github.com/commonsguy/cw-advandroid/tree/b01438e7f0fed8f795ddec4be43066905f03d0cc/AppWidget/TwitterWidget

Answer 2

Button is supported in appwidget so not sure what the problem is. Look at this example on how assign actions via views.setOnClickPendingIntent(R.id.YOURVIEW ID, yourIntent);

A RemoteViews object (and, consequently, an App Widget) can support the following layout classes:

FrameLayout LinearLayout RelativeLayout

And the following widget classes:

AnalogClock Button Chronometer ImageButton ImageView ProgressBar TextView Descendants of these classes are not supported.