Scroll down in vim omni completion popup

Question

Using a combination of Omni Completion and SuperTab, I'm able to do something like:

import random
random.

in Insert mode, then press Tab and have all of the options come up. Additionally, a popup window appears with documentation on the particular method that's currently selected. The problem is that only the first 12 lines or so of documentation are displayed in this popup window.

Is there a way to either switch to the popup window and scroll manually, or make the popup display bigger?

Answer 1

What you see is the extra information shown about matches in the preview window, configured via preview in 'completeopt'.

Normally, you could switch to the preview window (e.g. <C-W>P) and increase its size (e.g. <C-W>+), but that would abort completion when leaving insert mode. You have to change the default height of the preview window:

:set previewheight=20