title: How to make text as big as the width allows in flutter
body: <p>I have a Container where I need to show a barcode and I'd love to have the barcode to be as wide as possible on the screen.
  For now I set the font size at a reasonable size that suits all devices, but it's only temporary of course.
  How can I solve this? This is the code I am using for building the Widget.</p>
  <pre><code>@override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
        title: Text(_title),
      ),
      body: Container(
      padding: const EdgeInsets.all(12.0),
      child: Column(
        children: &lt;Widget&gt;[ 
          SizedBox(
            width: double.infinity,
            child: Text(_barcode, style: TextStyle(fontFamily: 'Code128', fontSize: 90.0))
          ),
          Text(_barcode, style: TextStyle(fontSize: 40.0))
          ]
        ),
      )
    );
  }
  </code></pre>