many text deferant style in one line flutter code example
Example: flutter text multistyle
var text = new RichText(
text: new TextSpan(
// Note: Styles for TextSpans must be explicitly defined.
// Child text spans will inherit styles from parent
style: new TextStyle(
fontSize: 14.0,
color: Colors.black,
),
children: <TextSpan>[
new TextSpan(text: 'Hello'),
new TextSpan(text: 'World', style: new TextStyle(fontWeight: FontWeight.bold)),
],
),
);