The first and only screen: a search field, the cards under it, a footer.

Typing filters. There is no mode to enter and no key to press first — the search field has the keyboard from the moment the UI opens, because searching is what this tool is for and anything else is a key you have to remember. So every printable character is the search field's, and everything the application does of its own is bound to a key the field does not want: the vertical arrows, Enter, ESC and a handful of Ctrl chords.

^I          the card in full          ^O ⏎   open the card in a browser
^F          the filter switches       ^R     reload the board
^A          what this is              ESC    clear the search, then quit
↑ ↓ ^P ^N   move the selection        ^C     quit
PgUp PgDn   a screen at a time

^I is the byte the Tab key sends — a terminal cannot tell the two apart — so Tab opens the card too, and the switches moved to ^F to make room.

q is a letter, so here it goes into the search field like any other. In the popups, where there is nothing to type into, it closes — see Gitpro.Views.Detail, Gitpro.Views.Filters and Gitpro.Views.About.

^A is the one binding taken off the search field: Atui.TextInput has it as readline's "start of the line", and Home still does that.

Loading

A board of a few hundred cards is several round trips, so the cards are fetched in an Atui.Fetch and the first frame is drawn before any of them have arrived. The UI is usable while it loads — the search field takes what you type, and the query is already applied when the cards land.

Who holds the filter

This view does. Gitpro.Views.Filters is pushed over it as a popup and sends the filter back on every toggle, so the list behind the popup narrows while the switches are being set rather than when the popup closes. While either popup is up, this view — which as the root view sees every key first — claims nothing, or the search field would eat the keys meant for them.

The switches for the labels and the assignees cannot exist before the cards do, so load/1 hands the filter the ones it found every time the board arrives. Switches already set survive that, and a popup that is open while it happens is told as well.