flutter/lib/pages/groupChat/index.dart

import 'package:easy_refresh/easy_refresh.dart';
import 'package:flutter/material.dart';

class StartGroupChatPage extends StatefulWidget {
  const StartGroupChatPage({super.key});

  @override
  State<StartGroupChatPage> createState() => _StartGroupChatPageState();
}

class _StartGroupChatPageState extends State<StartGroupChatPage> {
  final TextEditingController _searchController = TextEditingController();

  List<Map<String, dynamic>> dataList = [];
  List<Map<String, dynamic>> filteredList = [];
  Set<String> selectedIds = {}; // 已选中的用户 id
  int page = 1;
  bool hasMore = true;

  @override
  void initState() {
    super.initState();
    _loadData(reset: true);
  }

  @override
  void dispose() {
    _searchController.dispose();
    super.dispose();
  }

  Future<void> _loadData({bool reset = false}) async {
    if (reset) {
      page = 1;
      hasMore = true;
      dataList.clear();
    }

    // 模拟网络请求
    await Future.delayed(const Duration(seconds: 1));

    List<Map<String, dynamic>> newItems = List.generate(
      10,
      (index) => {"nickName": "用户 ${(page - 1) * 10 + index + 1}", "id": "${page}_$index"},
    );

    if (newItems.isEmpty) {
      hasMore = false;
    } else {
      dataList.addAll(newItems);
      page++;
    }

    _applySearch(_searchController.text);
  }

  void _applySearch(String query) {
    setState(() {
      if (query.isEmpty) {
        filteredList = List.from(dataList);
      } else {
        filteredList = dataList.where((item) => item["nickName"].toString().contains(query.trim())).toList();
      }
    });
  }

  void _toggleSelection(String id) {
    setState(() {
      if (selectedIds.contains(id)) {
        selectedIds.remove(id);
      } else {
        selectedIds.add(id);
      }
    });
  }

  Widget _buildCard({
    required IconData icon,
    required String title,
    required VoidCallback onTap,
  }) {
    return Card(
      color: Colors.white,
      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
      child: ListTile(
        leading: Icon(icon, color: Colors.black),
        title: Text(title, style: const TextStyle(fontSize: 16)),
        trailing: const Icon(Icons.arrow_forward_ios, size: 16),
        onTap: onTap,
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.white,
      appBar: AppBar(
        // backgroundColor: Colors.white,
        centerTitle: true,
        forceMaterialTransparency: true,
        bottom: PreferredSize(
          preferredSize: const Size.fromHeight(1.0),
          child: Container(
            color: Colors.grey[300],
            height: 1.0,
          ),
        ),
        title: const Text(
          "创建群聊",
          style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
        ),
      ),
      body: Column(
        children: [
          // 上半部分 - 两个卡片
          Padding(
            padding: const EdgeInsets.all(8.0),
            child: Column(
              children: [
                _buildCard(
                  icon: Icons.public,
                  title: "创建公开群",
                  onTap: () {
                    print("跳转到 创建公开群");
                  },
                ),
                _buildCard(
                  icon: Icons.group,
                  title: "创建好友群",
                  onTap: () {
                    print("跳转到 创建好友群");
                  },
                ),
              ],
            ),
          ),

          const Divider(),

          // 下半部分 - 搜索框 + 列表
          Expanded(
            child: Column(
              children: [
                // 搜索框
                Padding(
                  padding: const EdgeInsets.all(8.0),
                  child: TextField(
                    controller: _searchController,
                    decoration: InputDecoration(
                      hintText: "搜索用户昵称",
                      prefixIcon: const Icon(Icons.search),
                      border: OutlineInputBorder(
                        borderRadius: BorderRadius.circular(8),
                      ),
                    ),
                    onChanged: _applySearch,
                  ),
                ),

                // 列表
                Expanded(
                  child: EasyRefresh(
                    onRefresh: () async => _loadData(reset: true),
                    onLoad: () async {
                      if (hasMore) await _loadData();
                    },
                    child: ListView.builder(
                      itemCount: filteredList.length,
                      itemBuilder: (context, index) {
                        final item = filteredList[index];
                        final id = item["id"] as String;
                        final isSelected = selectedIds.contains(id);

                        return ListTile(
                          leading: CircleAvatar(
                            child: Text(item["nickName"].substring(0, 1)),
                          ),
                          title: Text(item["nickName"]),
                          trailing: Checkbox(
                            value: isSelected,
                            onChanged: (_) => _toggleSelection(id),
                          ),
                          onTap: () => _toggleSelection(id),
                        );
                      },
                    ),
                  ),
                ),
              ],
            ),
          ),
        ],
      ),

      // 底部按钮
      bottomNavigationBar: SafeArea(
        child: Padding(
          padding: const EdgeInsets.all(12.0),
          child: ElevatedButton(
            onPressed: selectedIds.isEmpty
                ? null
                : () {
                    print("选择了用户：$selectedIds");
                  },
            style: ElevatedButton.styleFrom(
              minimumSize: const Size.fromHeight(50),
              backgroundColor: selectedIds.isEmpty ? Colors.grey : Colors.blue,
            ),
            child: const Text(
              "发起聊天",
              style: TextStyle(fontSize: 16),
            ),
          ),
        ),
      ),
    );
  }
}