切换品牌时，消息加载优化 review by yewanwan

@@ -64,6 +64,7 @@ class DrawerContainer extends Component {
         this.props.actions.overview(brand.get('shopsId'));
         this.props.actions.brandRank(brand.get('shopsId'));
         this.props.actions.requestUnreadMsgNum(brand.get('shopsId'), 'N');
+        this.props.actions.getMsgList(brand.get('shopsId'));
     }
 
     render() {

@@ -56,17 +56,9 @@ class MessageContainer extends Component {
     }
 
     componentDidMount() {
-        // console.log('yeww componentDidMount');
         this.props.actions.getMsgList(this.props.home.brandId);
     }
 
-    componentWillReceiveProps() {
-        if (!this.props.message.isFetching && this.props.message.messageList.size == 0) {
-            // console.log('yeww componentWillReceiveProps');
-            this.props.actions.getMsgList(this.props.home.brandId);
-        }
-    }
-
     pressRow(rowID){
         this.props.actions.checkMessageDetail(rowID);
     }

@@ -54,7 +54,12 @@ export function requestMsgListFailure(error) {
 }
 
 export function getMsgList(brandId) {
-    return dispatch => {
+    return (dispatch, getState) => {
+        const {message} = getState();
+        if (!shouldRequestMsgList(message)) {
+            return;
+        }
+
 		dispatch(requestMsgList(brandId));
         return new MessageService().getMsgList(brandId)
             .then(json => {
@@ -66,6 +71,14 @@ export function getMsgList(brandId) {
 	};
 }
 
+export function shouldRequestMsgList(message) {
+    if (message.isFetching || message.messageList.size != 0) {
+        return false;
+    }
+
+    return true;
+}
+
 export function setMsgIsRead(brandId, messageId) {
     return dispatch => {
         dispatch(batchSetMsgRead());