title: Nullable Error because String is not nullable
body: <p>When I run my code, I get the following error message:</p>
  <p><code>The parameter 'name' can't have a value of 'null' because of its type, but the implicit default value is 'null'. Try adding either an explicit non-'null' default value or the 'required' modifier.</code></p>
  <p>Here's my code:</p>
  <pre><code>import 'package:flutter/widgets.dart';
  import 'package:flutter/material.dart';
  import 'checkbox.dart';
  
  class TodoItem extends StatefulWidget {
    final String name;
    final bool? isActive;
  
    const TodoItem({Key? key, this.name, this.isActive}) : super(key: key);
  
    @override
    _TodoItemState createState() =&gt; _TodoItemState();
  }
  
  class _TodoItemState extends State&lt;TodoItem&gt; {
    @override
    Widget build(BuildContext context) {
      return Row(
        mainAxisAlignment: MainAxisAlignment.spaceAround,
        children: [
          Text(
            widget.name,
            style: TextStyle(fontSize: 17, color: Colors.grey),
          ),
          Check(
            isActive: widget.isActive,
          )
        ],
      );
    }
  }
  </code></pre>
  <p>I tried to solve it with the responses to my last question but that didn't seem to work because apparently Strings are non-nunnable in Dart, even with a &quot;?&quot; besides them.</p>