trackoffical_app/lib/widget/region_pick.dart

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:trackoffical_app/pb.dart' as pb;
import 'package:trackoffical_app/widget/app_top_bar.dart';
import '../styles/theme.dart';

class _Region{
  pb.Region region= pb.Region();
  bool isSelected = false;
  List<_Region> children = [];
}

class RegionPickController extends GetxController {
  final List<pb.Region> regions = [];
  final found = <pb.Region>[].obs;
  final inputName = ''.obs;
  final regionLevel1 = <_Region>[].obs;
  final regionLevel2 = <_Region>[].obs;

  @override
  void onInit() {
    super.onInit();
    for (var one in regions){
      if(one.code.contains('0000')){
         regionLevel1.add(_Region()
          ..region = one);
      }
    }
  }

  onInputRegionName(String name) {
    final n = name.trim();

    inputName.value = n;
    found.clear();
    if (n.isNotEmpty) {
      for (var one in regions) {
        if (one.name.contains(name)) {
          found.add(one);
        }
      }
    }
  }
}

class RegionPick extends GetView<RegionPickController> {
  const RegionPick({super.key});

  static Future<pb.Region?> show(List<pb.Region> data) async {
    return await Get.to(const RegionPick(), binding: BindingsBuilder(() {
      var c = RegionPickController();
      c.regions.addAll(data);
      Get.put(c);
    }))!;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppTopBar(
        title: Container(
          decoration: const BoxDecoration(
              color: Colors.white,
              borderRadius: BorderRadius.all(Radius.circular(20))),
          child: TextField(
            decoration: const InputDecoration(
              hintText: '搜索',
              border: InputBorder.none,
              contentPadding: EdgeInsets.fromLTRB(14, 5, 70, 5),
              isDense: true,
            ),
            onChanged: (v) => controller.onInputRegionName(v),
            maxLines: 1,
          ),
        ),
        automaticallyImplyLeading: true,
      ),
      body: Obx(() {
        if (controller.inputName.value.isEmpty) {
          return _normalView(controller);
        } else {
          return _searchView(controller);
        }
      }),
    );
  }

  Widget _searchView(RegionPickController c) {
    return ListView.builder(
        itemCount: c.found.length,
        itemBuilder: (BuildContext context, int index) {
          return _foundEle(c.found[index]);
        });
  }

  Widget _normalView(RegionPickController c) {


    return Row(
      children: [
        Flexible(child: ListView.builder(
            itemCount: c.regionLevel1.length,
            itemBuilder: (BuildContext context, int index) {
              return _normalEle(c.regionLevel1[index]);
            })
        ),
        const Divider(height: 1),
        Flexible(child: ListView.builder(
            itemCount: c.regionLevel2.length,
            itemBuilder: (BuildContext context, int index) {
              return _normalEle(c.regionLevel2[index]);
            })
        ),
      ],
    ) ;
  }


  List<_Region> _getChildren(_Region data){
    var rexStr = data.region.code.replaceAll('0000', '[\\d]{4}');
    var rex = RegExp(rexStr);
    var out = <_Region>[];
    for (var one in controller.regions){
      if(one.code == data.region.code){
        continue;
      }
      if(one.code.contains(rex)){
        out.add(_Region()..region = one);
      }
    }
    return out;
  }

  Widget _normalEle(_Region data) {
    var bkColor = !data.isSelected? Colors.white:Colors.grey;
    return GestureDetector(
      onTap: () {
        var l = _getChildren(data);
        if(l.isEmpty){
          Get.back(result: data.region);
        }else{
          controller.regionLevel2.clear();
          controller.regionLevel2.addAll(l);
        }
      },
      child: Container(
        color: bkColor,
        padding: const EdgeInsets.only(left: 12, top: 12, bottom: 12),
        width: double.infinity,
        child: Text(data.region.name),
      ),
    );
  }
}

Widget _foundEle(pb.Region data) {
  return GestureDetector(
    onTap: () => Get.back(result: data),
    child: Container(
      padding: const EdgeInsets.only(left: 12),
      height: 48,
      width: double.infinity,
      child: Column(
        children: [
          Text(data.name),
          const Divider()
        ],
      ),
    ),
  );
}





void main() async {
  var c = RegionPickController();
  var regions = <pb.Region>[pb.Region()..name= '济南'];
  c.regions.addAll(regions);
  Get.put(c);
  runApp(GetMaterialApp(theme: appThemeData(), home: const RegionPick()));
}