Refactoring

1. Extension.getSettings() actually create a new instance every time
   it's called. To avoid that call it once when the extension is enabled
   and pass the object to all classes where it's needed.
2. Eliminate Extension.lookupByURL() as per code review feedback.
   Instead pass the extension object to all classes where needed.
3. Simplyfy destory in extension.js.

System_Monitor@bghome.gmail.com/extension.js

@@ -8,9 +8,9 @@ import * as View from './view.js';
 import * as PrefsKeys from './prefs_keys.js';
 
 const Timer = class {
-    constructor(params) {
-        this._settings = params.settings;
-        this._view = params.view;
+    constructor(view, settings) {
+        this._settings = settings;
+        this._view = view;
     }
 
     start(update_interval) {
@@ -42,6 +42,7 @@ const Timer = class {
     }
 
     destroy() {
+        this.stop();
         this._view.destroy();
         this._settings = null;
         this._view = null;
@@ -52,12 +53,12 @@ export default class SystemMonitorExtension extends Extension {
     #timer;
 
     enable() {
-        this.#timer = new Timer({view: new View.Menu({settings: this.getSettings()}), settings: this.getSettings()});
+        let settings = this.getSettings();
+        this.#timer = new Timer(new View.Menu(this, settings), settings);
         this.#timer.start();
     }
 
     disable() {
-        this.#timer.stop();
         this.#timer.destroy();
         this.#timer = null;
     }

System_Monitor@bghome.gmail.com/factory.js

@@ -56,7 +56,7 @@ IconFactory.prototype.concreteClass = IndicatorModule.Icon;
 // Create an indicator icon object, options will be passed to the real object's constructor.
 //
 // For working with themed icons see http://standards.freedesktop.org/icon-theme-spec/icon-theme-spec-latest.html
-IconFactory.prototype.create = function(type, options, can_show_activity) {
+IconFactory.prototype.create = function(type, options, can_show_activity, extensionObject) {
 	let default_options = {
 		style_class: 'system-status-icon system-monitor-icon',
 		reactive: true,
@@ -65,7 +65,6 @@ IconFactory.prototype.create = function(type, options, can_show_activity) {
 	}
 
 	let constructor_options = Object.assign(default_options, options);
-	let extensionObject = Extension.lookupByURL(import.meta.url);
 
 	if (type == PrefsKeys.STORAGE_METER) {
 		constructor_options.icon_name = 'drive-harddisk-symbolic';

System_Monitor@bghome.gmail.com/util.js

@@ -254,7 +254,6 @@ StopWatch.prototype.printElapsed = function (name) {
 export const logError = function(error) {
     let sourceFile = error.fileName;
     let sourceLine = error.lineNumber;
-    let extensionObject = Extension.lookupByURL(import.meta.url);
 
-    console.error(`Extension ${extensionObject.metadata.uuid}: "${error}" ${sourceFile}:${sourceLine}`);
+    console.error(`Extension [email protected]: "${error}" ${sourceFile}:${sourceLine}`);
 };

System_Monitor@bghome.gmail.com/view.js

@@ -12,13 +12,14 @@ import * as PrefsKeys from './prefs_keys.js';
 
 export const Menu = GObject.registerClass(
 class Menu extends PanelMenu.Button {
-    _init() {
+    constructor(extensionObject, settings) {
         let menuAlignment = 0.5;
-        let extensionObject = Extension.lookupByURL(import.meta.url);
-        super._init(menuAlignment);
+
+        super(menuAlignment);
 
         this._layout = new St.BoxLayout();
-        this._settings = extensionObject.getSettings();
+        this._settings = settings;
+        this._extensionObject = extensionObject;
         this._icons = {};
         this._meters = {};
         this._meter_widgets = {};
@@ -94,7 +95,7 @@ class Menu extends PanelMenu.Button {
     }
     _createIcon(type) {
         let can_show_activity = this._settings.get_boolean(PrefsKeys.SHOW_ACTIVITY);
-        let icon = FactoryModule.AbstractFactory.create('icon', type, {}, can_show_activity);
+        let icon = FactoryModule.AbstractFactory.create('icon', type, {}, can_show_activity, this._extensionObject);
         let meter = this._meters[type];
 
         if (meter == undefined) {
@@ -120,7 +121,7 @@ class Menu extends PanelMenu.Button {
         meter.addObserver(icon);
         this._layout.insert_child_at_index(icon, this.available_meters.indexOf(type));
         this._icons[type] = icon;
-        return FactoryModule.AbstractFactory.create('icon', type, {}, can_show_activity);
+        return FactoryModule.AbstractFactory.create('icon', type, {}, can_show_activity, this._extensionObject);
     }
     _destroyIcon(type) {
         let icon = this._icons[type];