Restrict Android Widget To One Instance Per Device

How could I restrict Android widgets in a way that only one instance can be created by the user at all times? A possible way is to store a SharedPreference including a counter vari

Solution 1:

How could I restrict Android widgets in a way that only one instance can be created by the user at all times?

You can't.

However, just because the user asks for multiple instances of your app widget does not mean you have to manage separate data for each. Just ignore the IDs and use the updateAppWidget() method that does not take any IDs.

Solution 2:

I do like this:

On Widget onUpdate method when user create first widget I save the ID of widget and update widget, for second time when onUpdate is called ( when added widget is updated ) then I check for the same id of widget and update it else tell the user that only one widget is allowed.

@OverridepublicvoidonUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {

        for (int appWidgetId : appWidgetIds) {

            //TinyDb is SharedPreferences ClassTinyDBtinydb=newTinyDB(context);
            int WidgetId= tinydb.getInt("WidgetID",-1);

            //Check if WidgetID is same as Added ID if yes UPDATEif (WidgetId == appWidgetId){
                updateAppWidget(context, appWidgetManager, appWidgetId);
                return;
            //Check if no widget is added then add widget and save widget ID to sharedPreferences
            } elseif (WidgetId == -1){
                tinydb.putInt("WidgetID", appWidgetId);
                updateAppWidget(context, appWidgetManager, appWidgetId);
                return;
            }
            else
                {
                //Make toast to tell the user that only one widget is allowed
                Toast.makeText(context, context.getResources().getString(R.string.Only_one_widget_allowed), Toast.LENGTH_SHORT).show();
                }
        }
    }

And don't forget: if user remove all widgets to save it to shared preferences, I use int -1 so I use this code:

@OverridepublicvoidonDisabled(Context context) {
        // Enter relevant functionality for when the last widget is disabledTinyDBtinydb=newTinyDB(context);
            tinydb.putInt("WidgetID", -1);
    }

and it works like a charm! Wholaa!