refactor(整理richText的说明):

lib/widgets/components/Bar/SnackBarAction/demo.dart

@@ -19,8 +19,8 @@ class _Demo extends State<SnackBarActionDemo> {
       return new Center(
         child: new Column(
           children: <Widget>[
-            new GestureDetector(
-              onTap: () {
+            new RaisedButton(
+              onPressed: () {
                 final snackBar = new SnackBar(
                   content: new Text('这是一个SnackBar, 右侧有SnackBarAction, 3秒后消失'),
                   backgroundColor:Color(0xffc91b3a),
@@ -39,8 +39,8 @@ class _Demo extends State<SnackBarActionDemo> {
              
               child: new Text('点我显示有action的SnackBar'),
             ),
-            new GestureDetector(
-              onTap: () async {
+            new RaisedButton(
+              onPressed: () async {
                 final snackBar = new SnackBar(
                   content: new Text('右侧无SnackBarAction, 3秒后消失'),
                   backgroundColor:Color(0xffc91b3a),

lib/widgets/elements/Form/Text/RichText/index.dart

@@ -11,33 +11,13 @@ const String intro = """
 
 无论是Text或者Text.rich, 查看源代码发现. 都是由RichText构建出来
 
-RichText的源码展示
 
-```
-// Text 源码
-@override
-  Widget build(BuildContext context) {
-      ...
-      Widget result = RichText(
-      ...
-    
-        style: effectiveTextStyle,
-        text: data,
-        children: textSpan != null ? <TextSpan>[textSpan] : null,
-      ),
-    );
-    ...
-    return result;
-  }
-```
-### **基本实例**
+### **基本用法**
+我们可以让一段文本通过使用不同的TextSpan显示不同的样式。比如我们让"Hello beautiful world"的每个单词都显示不同的样式.
 
 """;
-const String diff = """
 
 
-""";
-
 class Demo extends StatefulWidget {
   static const String routeName = '/element/Form/Text/RichText';
   _Demo createState() => _Demo();