code: public void setDialogContainer(StackPane dialogContainer) {
          if (dialogContainer != null) {
              this.dialogContainer = dialogContainer;
              // FIXME: need to be improved to consider only the parent boundary
              offsetX = dialogContainer.getBoundsInLocal().getWidth();
              offsetY = dialogContainer.getBoundsInLocal().getHeight();
              animation = getShowAnimation(transitionType.get());
          }
      }
docs: set the dialog container
  Note: the dialog container must be StackPane, its the container for the dialog to be shown in.
  
  @param dialogContainer