更改音量时更新小部件

Question

My app has 1 activity and 1 widget. I need to update my widget UI when users change the devices volume

In activity I can do it by registering a content observer:

public class SettingsContentObserver extends ContentObserver {
    private AudioManager audioManager;

    public SettingsContentObserver(Context context, Handler handler) {
        super(handler);
        audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
    }

    @Override
    public boolean deliverSelfNotifications() {
        return false;
    }

    @Override
    public void onChange(boolean selfChange) {
        int currentVolume = audioManager.getStreamVolume(AudioManager.STREAM_MUSIC);

        // Do something
    }
}

But with widget I do not know what to do. Can any help? Thanks in advance!

Answer 1

To achieve that, you need to make a Service with your ContentObserver , and onChange() just make a new RemoteViews.

So in OnChange() something like that:

AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(this);
int widgetIds[] = appWidgetManager.getAppWidgetIds(new ComponentName(context,
                WidgetClass.class));
RemoteViews views = new RemoteViews(context, R.id.widget_layout);//configure here your remoteViews
appWidgetManager.updateAppWidget(widgetIds, views);