title: @required annotation don't work properly on Flutter App using IntelliJ IDEA
body: <p>I have this code: </p>
  
  <pre><code>import 'package:flutter/material.dart';
  import 'package:flutter/widgets.dart';
  import 'package:meta/meta.dart';
  
  class RoundedButton extends StatelessWidget {
    final Color backgroundColor;
    final String textButton;
  
    const RoundedButton(
        {Key key, @required this.backgroundColor, @required this.textButton})
        : super(key: key);
  
    @override
    Widget build(BuildContext context) {
      return Container(
        alignment: Alignment.center,
        decoration: BoxDecoration(
            color: backgroundColor ?? Colors.grey,
            borderRadius: BorderRadius.circular(50)),
        width: getWidthByPercent(context, 90),
        height: getWidthByPercent(context, 15),
        child: Text(
          textButton ?? "",
          style: TextStyle(
              color: Colors.white,
              fontSize: getWidthByPercent(context, 7),
              fontWeight: FontWeight.w300),
        ),
      );
    }
  }
  </code></pre>
  
  <p>But when I use this widget on another page, the widget not warning me about the required parameters:</p>
  
  <pre><code>Widget build(BuildContext context) {
      return Positioned(
        top: getHeightByPercent(context, 60),
        bottom: getHeightByPercent(context, 1),
        left: getHeightByPercent(context, 1),
        right: getHeightByPercent(context, 1),
        child: Container(
          padding: EdgeInsets.all(10),
          decoration: BoxDecoration(
            color: whiteDefault,
            borderRadius: BorderRadius.circular(15),
          ),
          child: Column(
            children: &lt;Widget&gt;[
              Text(
                "SDS Connect",
                style: initialTitle(context, 10),
              ),
              Text(
                "The first to connect you with the information you need through NFC technology and innovate cloud based solutions",
                style: softGray(context, 5),
                textAlign: TextAlign.center,
              ),
              RoundedButton()
            ],
          ),
        ),
      );
  </code></pre>
  
  <p>Have some way to use this? I use this thing someway on others projects, but I don't remember how I was used, there's something that I can import on pubsbec.yaml.</p>
  
  <p><strong>UPDATE</strong></p>
  
  <p>I'm using IntelliJ IDEA and for some reason they not show the warning on the call of widget <code>RoundedButton()</code> but only on dart analyses windows, there's some way to show on widget call?</p>