✨ ModalBarrier、AnimatedModalBarrier、DefaultAssetBundle、DropdownButtonFormField、FormField、InheritedWidget、PaginatedDataTable

2020-12-20 16:58:17 +08:00
parent ccc9414285
commit da9764a51c
14 changed files with 581 additions and 45 deletions
--- a/lib/views/widgets/StatefulWidget/DropdownButtonFormField/node1_base.dart
+++ b/lib/views/widgets/StatefulWidget/DropdownButtonFormField/node1_base.dart
@@ -0,0 +1,69 @@
+import 'package:flutter/material.dart';
+
+/// create by 张风捷特烈 on 2020/9/21
+/// contact me by email 1981462002@qq.com
+/// 说明: 223 DropdownButtonFormField 表单下拉框
+/// 底层依赖 DropdownButton 实现，所以基本属性类似。但拥有 FormField 的特性，可以回调 onSaved、validator 方法。
+/// link: 55,222
+///
+//    {
+//      "widgetId": 223,
+//      "name": '表单下拉框简单使用',
+//      "priority": 1,
+//      "subtitle":
+//          "【items】 : 子组件列表   【List<DropdownMenuItem<T>>】\n"
+//          "【validator】 : 表单验证回调   【FormFieldValidator<T>】\n"
+//          "【onSaved】 : 表单保存回调   【FormFieldSetter<T>】\n"
+//          "其他属性详见 DropdownButton，表单校验特性详见 FormField。",
+//    }
+
+class DropdownButtonFormFieldDemo extends StatefulWidget {
+  @override
+  _DropdownButtonFormFieldDemoState createState() => _DropdownButtonFormFieldDemoState();
+}
+
+class _DropdownButtonFormFieldDemoState extends State<DropdownButtonFormFieldDemo> {
+  Color _color;
+  final _colors = [Colors.red, Colors.yellow, Colors.blue, Colors.green];
+  final _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??_colors[0],
+        ),
+
+        SizedBox(
+          width: 80,
+          child: DropdownButtonFormField<Color>(
+              value: _color,
+              elevation: 1,
+              hint: Text('选择颜色',style: TextStyle(fontSize: 12),),
+              icon: Icon(
+                Icons.expand_more,
+                size: 20,
+                color: _color,
+              ),
+            items: _buildItems(),
+              onChanged: (v) => setState(() => _color = v)
+          ),
+        )
+
+      ],
+    );
+  }
+
+  List<DropdownMenuItem<Color>> _buildItems() => _colors
+      .map((e) => DropdownMenuItem<Color>(
+      value: e,
+      child: Text(
+        _info[_colors.indexOf(e)],
+        style: TextStyle(color: e),
+      )))
+      .toList();
+}