初步优化项目结构

lib/widget_system/widgets/ProxyWidget/Directionality/node1_base.dart

@@ -0,0 +1,63 @@
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+
+/// create by 张风捷特烈 on 2020-03-23
+/// contact me by email 1981462002@qq.com
+/// 说明: 319 Directionality  定向性 为后代改变有textDirection属性的组件统一设置属性值,也可以通过Directionality.of(context)获取当前textDirection默认属性。
+//    {
+//      "widgetId": 319,
+//      "name": "Directionality基本使用",
+//      "priority": 1,
+//      "subtitle": "【textDirection】 : 文字排列方向   【TextDirection】\n"
+//          "【child】 : 子组件   【Widget】",
+//    }
+class DirectionalityDemo extends StatefulWidget {
+  @override
+  _DirectionalityDemoState createState() => _DirectionalityDemoState();
+}
+
+class _DirectionalityDemoState extends State<DirectionalityDemo> {
+  TextDirection _textDirection = TextDirection.rtl;
+
+  @override
+  Widget build(BuildContext context) {
+    return Directionality(
+      textDirection: _textDirection,
+      child: Container(
+        padding: EdgeInsets.all(8),
+        width: 250,
+        color: Colors.grey.withAlpha(33),
+        child: Column(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            Text(
+                'A widget that determines the ambient directionality of text and text direction sensitive render objects.'),
+            _buildSwitch(),
+            Text(
+                'The text direction from the closest instance of this class that encloses the given context.'),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildSwitch() {
+    return Row(
+            children: [
+              Switch(
+                value: _textDirection == TextDirection.rtl,
+                onChanged: (v) {
+                  setState(() {
+                    _textDirection =
+                        v ? TextDirection.rtl : TextDirection.ltr;
+                  });
+                },
+              ),
+              Text(
+                _textDirection.toString(),
+                style: TextStyle(color: Colors.blue, fontSize: 18),
+              )
+            ],
+          );
+  }
+}