Introduction

This GNOME Shell Extension aims to display information to center box. Using DBUS protocol, any application can add or remove text and icons in the upper bar, right after date & clock.

Installation

Create a symbolic link from your .local directory and enable extension

ln -s $PWD/generic-monitor@gnome-shell-extensions/ ~/.local/share/gnome-shell/extensions/ gnome-extensions enable generic-monitor@gnome-shell-extensions

Restart GNOME

DBUS protocol

All functions read JSON formatted parameters

notify(): { "group": "groupname", "items": [ { "name" : "", "box" : "", // Optional : left, right or center "text" : <text_object>, // Optional "icon" : <icon_object>, // Optional "popup" : <popup_object>, // Optional <signals_description>, // Optional }, ... ] } }

deleteItems(): { "items": ["@", ...] }

deleteGroups(): { "groups": ["", ...] }

openPopup(): { "item": "@" }

closePopup(): { "item": "@" }

togglePopup(): { "item": "@" }

DBUS object

<text_object> is defined as : { "text" : "Text to be displayed", "style" : "CSS style to be applied", // Optional }

<icon_object> is defined as : { "path" : "Icon path", "style" : "CSS style to be applied", // Optional }

<picture_object> is defined as : { "path" : "Icon path", "width" : XXX, // Optional : Force width in pixels, can be -1 for defaut value "height" : XXX, // Optional : Force height in pixels, can be -1 for defaut value }

<popup_object is defuned as : { "items": [<text_objects> and/or <picture_objects>] }

Signals description

Signals can be :

"on-click" : ["signal"|"delete"|"open-popup"|"close-popup"|"toggle-popup"] "on-dblclick" : ["signal"|"delete"|"open-popup"|"close-popup"|"toggle-popup"] "on-rightclick" : ["signal"|"delete"|"open-popup"|"close-popup"|"toggle-popup"] "on-rightdblclick" : ["signal"|"delete"|"open-popup"|"close-popup"|"toggle-popup"] "on-enter" : ["signal"|"delete"|"open-popup"|"close-popup"|"toggle-popup"] "on-leave" : ["signal"|"delete"|"open-popup"|"close-popup"|"toggle-popup"] "on-scroll" : ["signal"|"delete"|"open-popup"|"close-popup"|"toggle-popup"]

<!!> WARNING <!!> : It seems that GNOME 3.38.0 had some troubles managing on-enter/on-leave signal

Targets :

• signal : emit a signal to desktop application
• delete : Delete item
• open-popup : Open the popup if there is one
• close-popup : Close the popup if there is one
• toggle-popup : Toggle (open/close) the popup if there is one

Signal names emit when action "signal" is specified :

• onClick
• onRightClick
• onDblClick
• onRightDblClick
• onEnter
• onLeave
• onScrollUp
• onScrollDown

Each signal is sent with one parameter : "@"

Other signals are available when extension is activated/deactivated :

• onActivate
• onDeactivate

Example

You can test it with command line :

gdbus call --session --dest org.gnome.Shell --object-path /com/soutade/GenericMonitor --method com.soutade.GenericMonitor.notify '{"group":"new","items":[{"name":"first","on-click":"toggle-popup","text":"Hello","style":"color:green","popup":{"items":[{"picture":{"path":"/tmp/cat2.jpg"}}]}}]}'

gdbus call --session --dest org.gnome.Shell --object-path /com/soutade/GenericMonitor --method com.soutade.GenericMonitor.deleteGroups '{"groups":["new"]}'

Python example is available

Development

After doing code update, you can test it within a nested window. In other cases you have to restart GNOME.

dbus-run-session -- gnome-shell --nested [--wayland]

To see log & errors :

journalctl /usr/bin/gnome-shell

Licence

GNU GPL 3