how can I solve this problem. I know there are a lot of answers about this problem in internet. But I could not adapt them. My code for get values from WordPress website with WordPress own API.

file 1 main.dart

import 'dart:html';
import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'wp-api.dart';

void main() {
  runApp(benimApp());
}

class benimApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return GetMaterialApp(
      theme: ThemeData(),
      debugShowCheckedModeBanner: false,
      home: Scaffold(
        body: SafeArea(
          child: Column(children: [
            xMyHomePage(),
          ]),
        ),
      ),
    );
  }
}

class xMyHomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Container(
        child: FutureBuilder(
            future: fetchWpPosts(),
            builder: (context, snapshot) {
              if (snapshot.hasData) {
                return ListView.builder(
                  itemCount: 4,
                  itemBuilder: (BuildContext context, int index) {
                
                    Map wppost = snapshot.data[index];     
                                // return Text(wppost['title']['rendered']);
                  },
                );
              }
              return CircularProgressIndicator();
            }),
      ),
    );
  }
}

file 2 wp-api.dart

  import 'package:http/http.dart' as http;
import 'dart:convert';

Future<List> fetchWpPosts() async {
  final response = await http.get(
      Uri.parse('https://www.yazilimaktif.com/wp-json/wp/v2/posts?_embed'));
  var convertDataJson = jsonDecode(response.body);
  return convertDataJson;
}

I am getting error like this title

CodePudding user response：

Have you try with a return type of Future<List<dynamic>>, like this:

  Future<List<dynamic>> fetchWpPosts() async {
  try {
    final response = await http.get(
      Uri.parse('https://www.yazilimaktif.com/wp-json/wp/v2/posts?_embed'));
    if (response.statusCode == 200) {
      var convertDataJson = jsonDecode(response.body);
      return convertDataJson;
    } else {
      return [];
    }
  }
  catch (error) {
    return [];
  }
}

And add default value in case of errors to be shure don't returning null value.

CodePudding user response：

The problem is that data returned from snapshot is optional. So you need to unwrap it or check for null.

Your code will look like this:

 FutureBuilder(
        future: fetchWpPosts(),
        builder: (context, snapshot) {
          if (snapshot.hasData) {
            List<dynamic> returnedList = snapshot.data! as List;

            return ListView.builder(
              itemCount: 4,
              itemBuilder: (BuildContext context, int index) {
                Map wppost = returnedList[index];
                return Text(wppost['title']['rendered']);
              },
            );
          }
          return CircularProgressIndicator();
        }),