Create new event with emitter object to simplify code

src/common/EventEmitter.ts

@@ -14,11 +14,13 @@ export interface IEvent<T, U = void> {
 }
 
 export interface IEventEmitter<T, U = void> {
-  event: IEvent<T, U>;
   fire(arg1: T, arg2: U): void;
   dispose(): void;
 }
 
+export interface IEventWithEmitter<T, U = void> extends IEventEmitter<T, U>, IEvent<T, U> {
+}
+
 export class EventEmitter<T, U = void> implements IEventEmitter<T, U> {
   private _listeners: IListener<T, U>[] = [];
   private _event?: IEvent<T, U>;
@@ -64,6 +66,18 @@ export class EventEmitter<T, U = void> implements IEventEmitter<T, U> {
   }
 }
 
+export function initEvent<T, U = void>(): IEventWithEmitter<T, U> {
+  const emitter = new EventEmitter<T, U>();
+  const event = emitter.event;
+  Object.defineProperty(event, 'fire', {
+    value: emitter.fire.bind(emitter)
+  });
+  Object.defineProperty(event, 'dispose', {
+    value: emitter.dispose.bind(emitter)
+  });
+  return event as any;
+}
+
 export function forwardEvent<T>(from: IEvent<T>, to: IEventEmitter<T>): IDisposable {
   return from(e => to.fire(e));
 }