Change theming implementation - 1/2

components/lib/themes/utils/service.js

@@ -0,0 +1,36 @@
+function createService() {
+    const allHandlers = new Map();
+
+    return {
+        on(type, handler) {
+            let handlers = allHandlers.get(type);
+
+            if (!handlers) handlers = [handler];
+            else handlers.push(handler);
+
+            allHandlers.set(type, handlers);
+        },
+
+        off(type, handler) {
+            let handlers = allHandlers.get(type);
+
+            if (handlers) {
+                handlers.splice(handlers.indexOf(handler) >>> 0, 1);
+            }
+        },
+
+        emit(type, evt) {
+            let handlers = allHandlers.get(type);
+
+            if (handlers) {
+                handlers.slice().map((handler) => {
+                    handler(evt);
+                });
+            }
+        }
+    };
+}
+
+const ThemeService = createService();
+
+export default ThemeService;