hledger-ui keeps scrolling at the end of lists

[waj]

Hi! Is there any reason or real usefulness for making the lists keep scrolling once the cursor is at the end of the list?
I personally find this behavior annoying but also unexpected since it's different from any other TUI application or even graphical interfaces. Specially when the entire list of items fits in one page, it's odd that part of it becomes off screen. And even when it doesn't fit, I can see no point in not using as much screen as possible to display information instead of blank space.

I can see this is not a default behavior in brick, but instead made explicit for example here:

hledger/hledger-ui/Hledger/UI/AccountsScreen.hs

Lines 319 to 321 in 659e493

	-- DOWN key when selection is at the last item: scroll instead of moving, until maximally scrolled
	VtyEvent e | e `elem` moveDownEvents, isBlankItem mnextelement -> vScrollBy (viewportScroll $ l^.listNameL) 1
	where mnextelement = listSelectedElement $ listMoveDown l

I could try fixing this and send a PR unless there's a good reason or personal attachment to this behavior. 😄

[simonmichael]

Hi @waj.. it originally worked as you expected. It may not be optimal right now, but there was a reason. I think it was something to do with preserving a stable selection and/or scroll position as you enter and exit sub-screens.

[simonmichael]

Strangely it's not mentioned in the commit messages (or I failed to find it).

[simonmichael]

@waj: PS, if it wasn't clear, experiments with changing this are welcome. But that is one of the things to consider - how selection and scroll position change as you navigate, with various window and data sizes.