Unable to open a GtkWindow from a cinnamon applet - applet

Question

When I try to open a GtkWindow from a cinnamon applet, the entire desktop freezes.
No errors in the ~/.cinnamon/glass.log file.
const Gtk = imports.gi.Gtk;
function MyApplet(orientation)
{
this._init(orientation);
}
MyApplet.prototype =
{
__proto__: Applet.IconApplet.prototype,
_init: function(orientation)
{
Applet.IconApplet.prototype._init.call(this, orientation);
try {
this.set_applet_icon_name("dialog-question");
this.set_applet_tooltip("test");
}
catch (e) {
global.logError(e);
};
},
on_applet_clicked: function(event)
{
Gtk.init(null, 0);
let mwindow = new Gtk.Window ({type : Gtk.WindowType.TOPLEVEL});
mwindow.title = "Hello World!";
mwindow.connect ("destroy", function(){Gtk.main_quit()});
mwindow.show();
Gtk.main();
}
};
function main(metadata, orientation)
{
let myApplet = new MyApplet(orientation);
return myApplet;
}
The code is executed until Gtk.main() then no window is displayed and the desktop get frozen.
Anyone knows how to make it work correctly?

Answer 1

Javascript can't do multithreading, that's why calling Gtk.main(); breaks Cinnamon.
Cinnamon applet already runs a main loop and the call of Gtk.main(); tries to create another one.
So it's not possible to open a GtkWindow from a cinnamon applet directly in Javascript.
The solution could be to open a GtkWindow through a Python script, and to use DBus to communicate between the Cinnamon applet and the Python/GTK window.
Opened issue in Cinnamon GitHub

Answer 2

This is how you can do it:
const Gtk = imports.gi.Gtk;
const Util = imports.misc.util;
function MyApplet(orientation)
{
this._init(orientation);
}
MyApplet.prototype =
{
__proto__: Applet.IconApplet.prototype,
_init: function(orientation)
{
Applet.IconApplet.prototype._init.call(this, orientation);
try {
this.set_applet_icon_name("dialog-question");
this.set_applet_tooltip("test");
}
catch (e) {
global.logError(e);
};
},
on_applet_clicked: function(event)
{
//path to your applet directory; hardcoded for now!
let path="~/.local/share/cinnamon/applets/your_applet#you.org";
//create in your applet directory a file "yourgtkfile.js" and
//make it executable "chmod +x yourgtkfile.js"
Util.spawnCommandLine(path + "/yourgtkfile.js");
}
};
function main(metadata, orientation)
{
let myApplet = new MyApplet(orientation);
return myApplet;
}
You can copy/paste this in yourgtkfile.js. (Change #!/usr/bin/gjs with #!/usr/bin/cjs)
Or, this one (taken from here) (Change #!/usr/bin/gjs with #!/usr/bin/cjs):
#!/usr/bin/cjs
const Lang = imports.lang;
const Gtk = imports.gi.Gtk;
const Application = new Lang.Class({
//A Class requires an explicit Name parameter. This is the Class Name.
Name: 'Application',
//create the application
_init: function() {
this.application = new Gtk.Application();
//connect to 'activate' and 'startup' signals to handlers.
this.application.connect('activate', Lang.bind(this, this._onActivate));
this.application.connect('startup', Lang.bind(this, this._onStartup));
},
//create the UI
_buildUI: function() {
this._window = new Gtk.ApplicationWindow({ application: this.application,
title: "Hello World!" });
this._window.set_default_size(200, 200);
this.label = new Gtk.Label({ label: "Hello World" });
this._window.add(this.label);
},
//handler for 'activate' signal
_onActivate: function() {
//show the window and all child widgets
this._window.show_all();
},
//handler for 'startup' signal
_onStartup: function() {
this._buildUI();
}
});
//run the application
let app = new Application();
app.application.run(ARGV);
I supposed that you don't need to communicate with the app just launched :)