text window/box

I’m searching for an easy way to show a text window to the user with a close button at the bottom.
I know that there is e.g.

Code:
import xbmcgui

dialog = xbmcgui.Dialog()
dialog.ok('note', 'line1', 'line2', 'line3')

But this is too less text to show, I need something bigger.
Since Jarvis, there is also xbmcgui.Dialog().textviewer() but I would need something which works also with Isengard.

What options do I have?