Check Widget is Placed on Android Screen

Question

Can someone tell me how to check that my widget have been placed on the homescreen?

I have some code in my app that should run only if the widget is placed on the ho

Answer 1

I know it's an old question, but looking at this today I saw that there are a couple of problems with the accepted answer from @larsona1:

1. if the user cleared the shared preferences - there's still widget, but the app won't know about it.
2. if the user regret between "add widget" and before pressing "ok" - onEnabled will be called anyway, and a widget will be registered in the home screen even though there is no widget, and no way to remove it later. (it may be a bug in ADT home launcher).

I found a solution to the first problem. No shared preferences are needed at all, since it's unreliable anyway. It has to be checked in runtime.

// in some class you define a static variable, say in S.java
static boolean sWidgetMayExist = true;

In your widget provider:

// MyAppWidgetProvider.java
// to respond to runtime changes, when widgets are added and removed
@Override
public void onEnabled(Context context) {
    super.onEnabled(context);
    S.sWidgetMayExist = true;
}

@Override
public void onDisabled(Context context) {
    super.onDisabled(context);
    S.sWidgetMayExist = true;
}

And, in your service code add this:

AppWidgetManager manager = null;
RemoteViews views = null;
ComponentName widgetComponent = null;

    // ..and in your update thread

    if (!S.sWidgetMayExist) { return; }

if (manager == null || widgetComponent == null) {
    widgetComponent = new ComponentName(c,
            MyAppWidgetProvider.class);
    manager = AppWidgetManager.getInstance(c);
}

if (manager.getAppWidgetIds(widgetComponent) == null) {
    S.sWidgetMayExist = false;
}