From Zed's title bar, you can click on buttons to open three modal
pickers: remote projects, projects, and branches. All of these pickers
use the modal layer, which by default, renders them centered on the UI.
However, a UX issue we've been bothered by is that when you _click_ to
open them, they show up just way too far from where your mouse likely is
(nearby the trigger you just clicked). So, this PR introduces a
`ModalPlacement` enum to the modal layer, so that we can pick between
the "centered" and "anchored" options to render the picker. This way, we
can make the pickers use anchored positioning when triggered through a
mouse click and use the default centered positioning when triggered
through the keybinding.
One thing to note is that the anchored positioning here is not as
polished as regular popovers/dropdowns, because it simply uses the x and
y coordinates of the click to place the picker as opposed to using
GPUI's `Corner` enum, thus making them more connected to their triggers.
I chose to do it this way for now because it's a simpler and more
contained change, given it wouldn't require a tighter connection at the
code level between trigger and picker. But maybe we will want to do that
in the near future because we can bake in some other related behaviors
like automatically hiding the button trigger tooltip if the picker is
open and changing its text color to communicate which button triggered
the open picker.
https://github.com/user-attachments/assets/30d9c26a-24de-4702-8b7d-018b397f77e1
Release Notes:
- Improved the UX of title bar modal pickers (remote projects, projects,
and branches) by making them open closer to the trigger when triggering
them with the mouse.
a7d43063d4