监听分享按钮callback改为不是必传

20181112/SDK.ts

@@ -726,7 +726,7 @@ class WechatSDK {
         })
     }
     // 分享
-    public addShareEvent(shareInfo: shareInfo, callback) {
+    public addShareEvent(shareInfo: shareInfo, callback?) {
         const that = this;
         (wx as any).onShareAppMessage(() => {
             if (callback) callback();