Add event support to Tag.

Author: Nufflee

ts/html/Tag.ts

@@ -3,7 +3,8 @@ import UiComponent from '../UiComponent';
 export default class Tag implements UiComponent {
     constructor(private _name: string,
                 private _body?: UiComponent,
-                private _attrs?: {[key: string]: any}) {
+                private _attrs?: {[key: string]: any},
+                private _events?: {[key: string]: EventListenerOrEventListenerObject}) {
     }
 
     appendTo(entry: HTMLElement | null): void {
@@ -21,6 +22,12 @@ export default class Tag implements UiComponent {
             }
         }
 
+        if (this._events) {
+            for (let eventKey in this._events) {
+                element.addEventListener(eventKey, this._events[eventKey])
+            }
+        }
+
         if (this._body) {
             this._body.appendTo(element);
         }