GnomeShellGenericMonitor/README.md

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": ["<itemName>@<groupName>", ...]
  }

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

  openPopup():
  {
     "item": "<itemName>@<groupName>"
  }

  closePopup():
  {
     "item": "<itemName>@<groupName>"
  }

  togglePopup():
  {
     "item": "<itemName>@<groupName>"
  }


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 : "<itemName>@<groupName>"

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