I don't work with Graphical interfaces very much, most of my experience has been with Java. I realize the operating system provides some "native" controls that allow you to do things. What if I want to do things that are a little more fancy but feel like the native control?
What I'm thinking is having the simplicity of editing in a TextArea while provide the ability to collapse lists just like a tree. I would also like to be able to display text between lines that the user could click, it should be aligned under the right most text and be smaller.
I'm not thinking in terms of any language or GUI library. Just wondering how to go about creating something like this. Would I overlay some drawing onto the TextArea which would scroll with it? Would I use something like Cairo and build my own text field losing built in copy and paste...
What do other text editors use that allow them to fold code?