nanogui: Thread: How to move the cursor in flnx

Hello :

     I want to change the mouse and cursor position in the window just throght the code ,how can I do ? Does the flnx provide the interface to do it ? I find through all the classes : Fl_Window and Fl_Group and Fl_Widget ,but I can't find the method to do this . 

        Thanks in advance !
                           zxg