Update README.md

README.md

@@ -1,5 +1,5 @@
 # k_chart
-A Flutter K Chart.
+A Flutter K Chart.And easy to use.
 
 ![vertical](https://github.com/mafanwei/k_chart/blob/master/example/images/demo.gif)
 ## Getting Started
@@ -13,4 +13,38 @@ or use latest：
 k_chart:
     git:
       url: https://github.com/mafanwei/k_chart
-```
+```
+#### Usage
+
+use k line chart:
+```
+Container(
+              height: 450,
+              width: double.infinity,
+              child: KChartWidget(
+                datas,//Required，Data must be an ordered list，(history=>now)
+                isLine: isLine,//Decide whether it is k-line or time-sharing
+                mainState: _mainState,//Decide what the main view shows
+                secondaryState: _secondaryState,//Decide what the sub view shows
+                fixedLength: 2,//Displayed decimal precision
+                timeFormat: TimeFormat.YEAR_MONTH_DAY,
+                onLoadMore: () {},//Called when the list is swiped to the far left,use it load history.
+                maDayList: [5,10,20],//Display of ma
+                bgColor: [Colors.black],//The background color of the chart is gradient
+                isChinese: true,//Graphic language
+                isOnDrag: (isDrag){},// true is on Drag.Don't load data while Draging.
+              ),
+            ),
+```
+
+use depth chart:
+```
+DepthChart(_bids, _asks) //Note: Datas must be an ordered list，
+```
+#### Donate
+
+Buy the writer a cup of coffee.
+
+![alipay](https://img-blog.csdnimg.cn/20181205161540134.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3F3ZTI1ODc4,size_16,color_FFFFFF,t_70)
+
+![wechat](https://img-blog.csdnimg.cn/20181205162201519.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3F3ZTI1ODc4,size_16,color_FFFFFF,t_70)