code: @Nullable public static <P> P getPresenter(@NonNull Activity activity, @NonNull String viewId) {
      if (activity == null) {
        throw new NullPointerException("Activity is null");
      }
  
      if (viewId == null) {
        throw new NullPointerException("View id is null");
      }
  
      ActivityScopedCache scopedCache = getActivityScope(activity);
      return scopedCache == null ? null : (P) scopedCache.getPresenter(viewId);
    }
docs: Get the presenter for the View with the given (Mosby - internal) view Id or <code>null</code>
  if no presenter for the given view (via view id) exists.
  
  @param activity The Activity (used for scoping)
  @param viewId The mosby internal View Id (unique among all {@link MvpView}
  @param <P> The Presenter type
  @return The Presenter or <code>null</code>