title: Flutter how to map a completed Future object in List map
body: <pre><code>Future&lt;List&lt;Future&lt;News&gt;&gt;&gt; getNewsList(skipItems) async {
      final response = await http.get(
          'https://hacker-news.firebaseio.com/v0/topstories.json?print=pretty');
  
      if (response.statusCode == 200) {
        // If the call to the server was successful, parse the JSON
        var responseNewsList = json.decode(response.body);
        newsList = responseNewsList as List;
        var resNewsList = (responseNewsList as List)
            .skip(skipItems)
            .take(20)
            .map((id) =&gt;  this.fetchNewsDetails(id))
            .toList();
  
        return resNewsList;
      } else {
        // If that call was not successful, throw an error.
        throw Exception('Failed to load post');
      }
  }
  
  Future&lt;News&gt; fetchNewsDetails(id) async {
      final response = await http.get(
          'https://hacker-news.firebaseio.com/v0/item/$id.json?print=pretty');
  
      if (response.statusCode == 200) {
        // If the call to the server was successful, parse the JSON
        return News.fromJson(json.decode(response.body));
      } else {
        // If that call was not successful, throw an error.
        throw Exception('Failed to load post');
      }
  }
  </code></pre>
  
  <p>So as the code you can see that I try to get a list of top stories post but the response only return me a list of ids, so I will need call another api to get the post detail, in the way above I will need to use twice <code>Future Builder</code> for display the content, the way works but is there anyway for me to wait the response back and have the post result in the mapping function?</p>