In my Sway configuration I have two lines that start an application in a specific way:
bindsym Mod4+e exec ~/.config/sway/run-or-raise Emacs emacs
bindsym Mod4+w exec ~/.config/sway/run-or-raise Firefox firefox
What does this do?
First, the “exec” clause calls a python script, run-or-raise.
This python scripts wants two arguments. The first one is a container name. It
uses swaymsg -t get_tree to get all outputs, work spaces and containers. And
then it looks for any container (that is: application, Wayland client) that
matches the name. This match is actually done case insensitive.
Now we can have 3 outcomes:
- It finds no matching container. In that case, it just starts one with the 2nd command line argument for the binary / script. And since some applications (e.g. Firefox) can take a bit time to start, a short startup notification will be displayed.
- It finds exactly one matching container. This container will then get the
focus using
swaymsg [con_id=...] focus. - It finds several matching containers. Then again the logic is like this:
- none of them has the focus: select the first one to get the focus
- one of them already has focus: focus the next one, possibly wrapping around to the start of the list.
And now, with that I can use Logo+e to switch to my Emacs windows, wherever I
am. Normally, Emacs is already started, thanks to my default Sway layout
setup.
And Logo+w starts a web browser (here Firefox). If already running, it will be
focused. If several separate windows are open, one after the other will be
selected.
I could use tabs as well, but some web applications slow down if they are in an unselected tab. So I tear out these tabs and put them in separate windows. And I can quickly select them that way.
This is a (tiny) part of my Sway configuration.