Create/Init RichEditor dynamically without page reload

The situation is, that I need to create a RichEditor in my plugin page dynamically. When the user selects an issue from a list, I create the html code for the RichEditor and I add it to the page (without page reload, with javascript).
But it looks like that I need to call some JS function that initializes this html code to create the “real” RichEditor.

Can anybody help?

Thx!