UI
Through the built-in Editor of the Engine, after making a UI file, you can load it through the loader provided by Gui object and add it to SceneBox to display it. Reference code:
function on_begin_play(component)
local gui = nx_value("gui");
local lscene = component.Scene
local scenebox = lscene.SceneBox
local loader = gui.Loader
local form = loader:LoadForm(nx_resource_path(), "skin\\test_form.ui")
form.lscene = lscene
scenebox.test_form = form
scenebox:Add(form)
end