初步优化项目结构

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

@@ -0,0 +1,65 @@
+import 'package:flutter/material.dart';
+
+/// create by 张风捷特烈 on 2020-03-30
+/// contact me by email 1981462002@qq.com
+/// 说明:
+//    {
+//      "widgetId": 181,
+//      "name": 'DropDownButtonHideUnderline使用',
+//      "priority": 1,
+//      "subtitle":
+//          "【child】 : 子组件   【Widget】\n",
+//    }
+class CustomDropDownButtonHideUnderline extends StatefulWidget {
+  @override
+  _CustomDropDownButtonHideUnderlineState createState() =>
+      _CustomDropDownButtonHideUnderlineState();
+}
+
+class _CustomDropDownButtonHideUnderlineState
+    extends State<CustomDropDownButtonHideUnderline> {
+  Color _color = Colors.red;
+  final List<Color> _colors = [
+    Colors.red,
+    Colors.yellow,
+    Colors.blue,
+    Colors.green
+  ];
+  final List<String> _info = ["红色", "黄色", "蓝色", "绿色"];
+
+  @override
+  Widget build(BuildContext context) {
+    return Wrap(
+      children: <Widget>[
+        Container(
+          margin: EdgeInsets.symmetric(horizontal: 20),
+          width: 50,
+          height: 50,
+          color: _color,
+        ),
+        DropdownButtonHideUnderline(
+          child: DropdownButton<Color>(
+              value: _color,
+              elevation: 1,
+              icon: Icon(
+                Icons.expand_more,
+                size: 20,
+                color: _color,
+              ),
+              items: _buildItems(),
+              onChanged: (Color? color) =>
+                  setState(() => _color = color ?? _color)),
+        ),
+      ],
+    );
+  }
+
+  List<DropdownMenuItem<Color>> _buildItems() => _colors
+      .map((e) => DropdownMenuItem<Color>(
+          value: e,
+          child: Text(
+            _info[_colors.indexOf(e)],
+            style: TextStyle(color: e),
+          )))
+      .toList();
+}