I am using FLUID to design my fltk window, but one time I closed the fltk window which is under design in FLUID by the upper-right close button in the window, and then saved the .fl file in Widgets Browser , then when I reopen the .fl file in Widgets Browser, my fltk window disapeard, only left the Widgets Browser, and the widgets Bin.
I don't know how to make it appeare.

The FLUID I am using is included in FLTK 1.1.6

I don't know whether it is a bug, or something else. :-(

Hi Realkin and welcome to GIDForums™.

Try to double click on the window descriptor in the fluid list (tree view thing) and see if that pulls the window back up.

Thanks for your reply.

Now I can make it reappear.

To make it reappear , we should double click the "double window" thing in the widgets browser, otherwise, It cannot work.