Why is my vim colorscheme changing when I change buffers

Question

I have some prefered colorscheme on some filetypes, but when I open another file (different file type with different colorscheme) and come back on a previous one, the new co

Answer 1

Ingo's answer is smarter but these autocommands

autocmd BufEnter *     colorscheme default
autocmd BufEnter *.php colorscheme desert
autocmd BufEnter *.py  colorscheme darkblue

should work. Well, they work, here.