There is currently no way to use a Filter for a Resource in the default view. However, for the desired outcome, it’s possible to use a combination of the Nova indexQuery method and Laravels global scopes.

1. Create a scope with the desired default filter: php artisan make:scope DefaultFilterScope
2. Use this scope in the indexQuery method of the Nova Resource like so:
   public static function indexQuery(NovaRequest $request, $query) { return $query->withGlobalScope(DefaultFilterScope::class, new DefaultFilterScope); }
3. In the other Filters for this Resource, add $query = $query->withoutGlobalScope(DefaultFilterScope::class); in the first line of the apply method, to remove the Global Scope added in the indexQuery method, and just use whatever the Filter does.

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