Although there is no error in the application that I want to show the weather from the internet, a white screen appears

Question

launchUrl not working

import 'package:flutter/material.dart';
import 'package:haber_app/data/new_service.dart';
import 'package:haber_app/models/articles.dart';
import 'package:url_launcher/url_launcher.dart';

class Home extends StatefulWidget {
  @override
  State<Home> createState() => _HomeState();
}

class _HomeState extends State<Home> {
  List<Articles> articles = [];

  @override
  void initState() {
    NewsService.getNews().then((value) {
      setState(() {
        articles = value!;
      });
    });
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Haberler'),
        centerTitle: true,
      ),
      body: Center(
          child: ListView.builder(
              itemCount: articles.length,
              itemBuilder: (context, index) {
                return Card(
                  child: Column(
                    children: [
                      Image.network(articles[index].urlToImage!),
                      ListTile(
                        leading: Icon(Icons.arrow_drop_down_circle),
                        title: Text(articles[index].title!),
                        subtitle: Text(articles[index].author!),
                      ),
                      Padding(
                        padding: const EdgeInsets.all(16.0),
                        child: Text(
                            'açıklama açıklama açıklamaaçıklama açıklamaaçıklama'),
                      ),
                      ButtonBar(
                        alignment: MainAxisAlignment.start,
                        children: [
                          ElevatedButton(
                              onPressed: () async {
                                await launchUrl(articles[index].url);
                              },
                              child: Text('Habere git'))
                        ],
                      )
                    ],
                  ),
                );
              })),
    );
  }
}

Link of the code: https://github.com/ghedtoboss/haber_app

Answer 1

I am making a pull request, check the changes and merge. haber_app/pull/1

Changes are on

source.dart

class Source {
  String? id;
  String? name;

  Source({this.id, this.name});

  Source.fromJson(Map<String, dynamic> json) {
    id = json['id'];
    name = json['name'];
  }

  Map<String, dynamic> toJson() {
    final Map<String, dynamic> data = Map<String, dynamic>();
    data['id'] = id;
    data['name'] = name;
    return data;
  }
}

news.dart

import 'articles.dart';

class News {
  String? status;
  int? totalResults;
  List<Articles>? articles;

  News({this.status, this.totalResults, this.articles});

  News.fromJson(Map<String, dynamic> json) {
    status = json['status'];
    totalResults = json['totalResults'];
    if (json['articles'] != null) {
      articles = <Articles>[];
      json['articles'].forEach((v) {
        print(v);
        articles!.add(Articles.fromJson(v));
      });
    }
  }

  Map<String, dynamic> toJson() {
    final Map<String, dynamic> data = Map<String, dynamic>();
    data['status'] = status;
    data['totalResults'] = totalResults;
    if (articles != null) {
      data['articles'] = articles!.map((v) => v.toJson()).toList();
    }
    return data;
  }
}

NewsService

import 'package:haber_app/models/articles.dart';
import 'package:haber_app/models/news.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';

class NewsService {
  static NewsService _singleton = NewsService._internal();
  NewsService._internal();

  factory NewsService() {
    return _singleton;
  }

  static Future<List<Articles>?> getNews() async {
    String api =
        'https://newsapi.org/v2/top-headlines?country=tr&category=business&apiKey=0002834b74c04acd987883986ea38f96';

    final Uri url = Uri.parse(api);
    final response = await http.post(url);

    if (response.body.isNotEmpty) {
      final responseJson = json.decode(response.body);
      News news = News.fromJson(responseJson);
      return news.articles;
    }
    return null;
  }
}

On body

import 'package:flutter/material.dart';
import 'package:haber_app/data/new_service.dart';
import 'package:haber_app/models/articles.dart';
import 'package:url_launcher/url_launcher.dart';

class Home extends StatefulWidget {
  @override
  State<Home> createState() => _HomeState();
}

class _HomeState extends State<Home> {
  List<Articles> articles = [];

  @override
  void initState() {
    super.initState();
    loadData();
  }

  loadData() async {
    NewsService.getNews().then((value) {
      print(value);
      setState(() {
        articles = value ?? [];
      });
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Haberler'),
        centerTitle: true,
      ),
      body: Center(
          child: articles.isEmpty
              ? Text("loading or something")
              : ListView.builder(
                  itemCount: articles.length,
                  itemBuilder: (context, index) {
                    return Card(
                      child: Column(
                        children: [
                          if (articles[index].urlToImage != null)
                            Image.network(articles[index].urlToImage!),
                          ListTile(
                            leading: Icon(Icons.arrow_drop_down_circle),
                            title: Text(articles[index].title ?? ""),
                            subtitle: Text(articles[index].author ?? ""),
                          ),
                          Padding(
                            padding: const EdgeInsets.all(16.0),
                            child: Text(
                                'açıklama açıklama açıklamaaçıklama açıklamaaçıklama'),
                          ),
                          ButtonBar(
                            alignment: MainAxisAlignment.start,
                            children: [
                              ElevatedButton(
                                  onPressed: () async {
                                    if (articles[index].url == null) {
                                      return;
                                    }
                                    await launchUrl(
                                        Uri.parse(articles[index].url!));
                                  },
                                  child: Text('Habere git'))
                            ],
                          )
                        ],
                      ),
                    );
                  })),
    );
  }
}

You need to use Uri to launch

onPressed: () async {
  if (articles[index].url == null) {
    return;
  }
  await launchUrl(
      Uri.parse(articles[index].url!));
},

Also make sure to set up the configurationsection

More about url_launcher