From f6866c97d05576a7378258a6a70e9e448516a389 Mon Sep 17 00:00:00 2001
From: zx <acczhuang@163.com>
Date: Fri, 9 Aug 2019 16:05:20 +0800
Subject: [PATCH] wancheng

---
 Observable.js | 19 +++++++++++++++++++
 PubSub.js     |  7 +++++++
 2 files changed, 26 insertions(+)

diff --git a/Observable.js b/Observable.js
index 03545cd..71d937e 100644
--- a/Observable.js
+++ b/Observable.js
@@ -11,12 +11,23 @@ class ObserverList {
   }
   add(observer) {
     // todo add observer to list
+    return this.observerList.push(observer);
   }
   remove(observer) {
     // todo remove observer from list
+    const index = this.observerList.indexOf(observer);
+    if (index !== -1) {
+      this.observerList.splice(index, 1);
+    }
   }
   count() {
     // return observer list size
+    return this.observerList.length
+  }
+  get(index){
+    if( index > -1 && index < this.observerList.length ){
+      return this.observerList[ index ];
+    }
   }
 }
 
@@ -26,12 +37,20 @@ class Subject {
   }
   addObserver(observer) {
     // todo add observer
+    this.observers.add(observer);
   }
   removeObserver(observer) {
     // todo remove observer
+    this.observers.remove(observer);
   }
   notify(...args) {
     // todo notify
+    if(this.observers.count() > 0) {
+      const length = this.observers.count();
+      for (let i = 0; i < length; i++) {
+        this.observers.get(i).update(...args);
+      }
+    }
   }
 }
 
diff --git a/PubSub.js b/PubSub.js
index 0c7999e..c4b7ecb 100644
--- a/PubSub.js
+++ b/PubSub.js
@@ -13,14 +13,21 @@ module.exports = class PubSub {
 
   subscribe(type, fn) {
     // todo subscribe
+    let topic = this.subscribers[type];
+    if (!topic) {
+      this.subscribers[type] = [];
+    }
+    this.subscribers[type].push(fn);
   }
 
   unsubscribe(type, fn) {
     // todo unsubscribe
+    delete this.subscribers[type];
   }
 
   publish(type, ...args) {
     // todo publish
+    this.subscribers[type] && this.subscribers[type].forEach(fn => fn(...args));
   }
 
 }