Question

我正在尝试在扩展图块中显示我的json数组数据。我能够在扩展图块中显示数据，但是当我按扩展图块时，它什么也没显示。按下扩展磁贴时无显示。

JSON：

{

    “name”: “kris”,
    “age”: 13,
    “class”: “13A”,

}

Expansion_tile.dart：

import 'dart:async';
import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;

var userData = [];

class ActiveUser extends StatefulWidget {
  @override
  ActiveUserState createState() => new ActiveUserState();
}

class ActiveLevelState extends State<ActiveUser> {
  final String url = "http://35.186.145.243:8080/user?user_id=user3";

  List data;

  @override
  void initState() {
    super.initState();
    this.getJsonData();
  }

  Future<String> getJsonData() async {
    var response = await http.get(
      Uri.encodeFull(url),
      headers: {"Accept": "application/json"},
    );

    var extractdata = json.decode(response.body);
    data = extractdata['user'];
    userData = data;

    setState(
      () {
        var extractdata = json.decode(response.body);
        data = extractdata['user'];
      },
    );
    return "Success";
  }

  @override
  Widget build(BuildContext context) {
    return ListView.builder(
      itemBuilder: (BuildContext context, int index) => Card(
            child: SingleChildScrollView(
              child: StuffInTiles(userData[index]['name']),
            ),
          ),
      itemCount: userData.length,
    );
  }
}

class StuffInTiles extends StatelessWidget {
  final String elementList;
  StuffInTiles(this.elementList);

  @override
  Widget build(BuildContext context) {
    return _buildTiles();
  }

  Widget _buildTiles() {
    if (userData.length == 0)
      return ListTile(
        title: Text("Test"),
      );
    return ExpansionTile(
      title: Text(elementList),
      children: map(_buildTiles).toList(),
    );
  }
}

我知道我应该在扩展图块中的子项下写一些内容，以便在按下时显示内容，但是我不确定如何显示子项，因为尝试时会给我错误。

Answer 1

我已经知道答案了！只需在扩展图块的children属性下调用_getChildren方法即可：

List<dynamic> _getChildren() {
      List<Widget> children = [];
      levelsData.forEach((element) {
        children.add(GestureDetector(
          onTap: () => print("Tapped"),
          child: ListTile(
            dense: true,
            title: Text("@" + element['name'].toString()),
            subtitle: Text(element['age'].toString()),
          ),
        ));
      });
      return children;
    }

return ExpansionTile(
      title: Text(elementList),
      children: _getChildren(),
    );

在扩展图块中显示json数组-颤振

1 个答案: