Changing profiles based on the active window title/class

[teras]

Recapping some info based on previous discussions.

When the focus moved to another application's window then (probably) a new profile should be selected. For example the focus is on FIrefox, now it's on Nemo, now it's on the Desktop (i.e. none).

This is a feature of the app itself, and this is what other applications are doing, and maybe the paradigm should be similar.

StreamController screenshot

StreamDeck screenshot

Demo code in rust

Cargo.toml

```toml [package] name = "focus_listener" version = "0.1.0" edition = "2021" [dependencies] x11rb = "0.13.1" ```

test.rs

```rust use std::error::Error; use x11rb::atom_manager; use x11rb::connection::Connection; use x11rb::protocol::xproto::{AtomEnum, ConnectionExt, EventMask, PropertyNotifyEvent, Window}; use x11rb::rust_connection::RustConnection; atom_manager! { pub Atoms: AtomsCookie { _NET_ACTIVE_WINDOW, WM_CLASS, _NET_WM_NAME, WM_NAME, UTF8_STRING, } } struct X11FocusListener { conn: RustConnection, root: Window, atoms: Atoms, last_active_window: Option, } impl X11FocusListener { fn new() -> Result> { let (conn, screen_num) = RustConnection::connect(None)?; let screen = &conn.setup().roots[screen_num]; let root = screen.root; let atoms = Atoms::new(&conn)?.reply()?; conn.change_window_attributes(root, &x11rb::protocol::xproto::ChangeWindowAttributesAux::new() .event_mask(EventMask::PROPERTY_CHANGE | EventMask::SUBSTRUCTURE_NOTIFY))?; for child in conn.query_tree(root)?.reply()?.children { conn.change_window_attributes(child, &x11rb::protocol::xproto::ChangeWindowAttributesAux::new() .event_mask(EventMask::PROPERTY_CHANGE))?; } Ok(Self { conn, root, atoms, last_active_window: None, }) } fn get_next_focus_change(&mut self) -> Result<(String, String), Box> { loop { let event = self.conn.wait_for_event()?; if let x11rb::protocol::Event::PropertyNotify(PropertyNotifyEvent { atom, .. }) = event { if atom == self.atoms._NET_ACTIVE_WINDOW { if let Ok(reply) = self.conn.get_property(false, self.root, self.atoms._NET_ACTIVE_WINDOW, AtomEnum::WINDOW, 0, 1)?.reply() { if let Some(window_id) = reply.value32().and_then(|mut v| v.next()) { if self.last_active_window != Some(window_id) { self.last_active_window = Some(window_id); let wm_class = self.get_window_class(window_id)?; let wm_title = self.get_window_title(window_id)?; return Ok((wm_title.unwrap_or_default(), wm_class.unwrap_or_default())); } } } } } } } fn get_window_class(&self, window: Window) -> Result, Box> { if let Ok(reply) = self.conn.get_property(false, window, self.atoms.WM_CLASS, AtomEnum::STRING, 0, 1024)?.reply() { if let Some(value) = reply.value8() { return Ok(Some(String::from_utf8_lossy(&value.collect::>()).split(' ').filter(|s| !s.is_empty()).collect::>().join("."))); } } Ok(None) } fn get_window_title(&self, window: Window) -> Result, Box> { if let Ok(reply) = self.conn.get_property(false, window, self.atoms._NET_WM_NAME, self.atoms.UTF8_STRING, 0, 1024)?.reply() { if let Some(value) = reply.value8() { return Ok(Some(String::from_utf8_lossy(&value.collect::>()).to_string())); } } if let Ok(reply) = self.conn.get_property(false, window, self.atoms.WM_NAME, AtomEnum::STRING, 0, 1024)?.reply() { if let Some(value) = reply.value8() { return Ok(Some(String::from_utf8_lossy(&value.collect::>()).to_string())); } } Ok(None) } } fn main() -> Result<(), Box> { let mut listener = X11FocusListener::new()?; loop { let (title, class) = listener.get_next_focus_change()?; println!("Class: {}", class); println!("Title: {}", title); } } ```

Some key notes need discussion

• The solution can't be multi platform, since i.e. Wayland doesn't support this (in many cases, like in Gnome)
• About being a plugin, I think we agreed to it
• Something I forgot?

[ninjadev64]

All good :)

Looking forward to it!

[teras]

Actually I am not sure I can do this , at least alone. I know that I requested it, but it's not something I feel I can manage there.

[ninjadev64]

Well, you've done 75% of the work already! If you have Discord or Matrix, feel free to join the OpenDeck chats and I can show you which bits of the OpenDeck internals you need to interface with ;)

[teras]

I might have an old Discord account. We''l find some time that both of us are online.

[ninjadev64]

Awesome