How do I make some text tappable (respond to taps) in Flutter?

One more approach

Create the function that returns tapable widget:

Widget tapableText(String text, Function onTap) {
  return GestureDetector(
    onTap: onTap,
    child: Text(text),
  );
}

Usage example:

...
child: tapableText('Hello', () { print('I have been tapped :)'); }),
...

As seen on this answer, you can use an InkWell or a gesture detector.

For example

InkWell(
    child: Text("Hello"),
    onTap: () {print("value of your text");},
)

Or

var textValue = "Flutter"
InkWell(
    child: Text(textValue),
    onTap: () {print(textValue);},
)

EDIT : As Collin Jackson suggested, you can also use a FlatButton

FlatButton(
  onPressed: () {print("Hello world");},
  child: Text("Hello world"),
);

If you don't need or require material (FlatButton, InkWell, etc), you can use GestureDetector:

GestureDetector(
  onTap: () { print("I was tapped!"); },
  child: Text("Hello world"),
)

You can also make the text appear in the form of a URL like so:

new FlatButton(
  onPressed: () {print("You've tapped me!")},
  child: Text(
    "Tap me!", 
    style: TextStyle(color: Colors.blue, decoration: TextDecoration.underline)),
);

you can use Rich text for tappable text:-

Divide the text in Text Span accordingly and use Tap Gesture in that text you want to make tappable.

  TapGestureRecognizer _termsConditionRecognizer;
  TapGestureRecognizer _privacyPolicyRecognizer;

  @override
  void dispose() {
    _privacyPolicy.dispose();
    _termsCondition.dispose();
    super.dispose();
  }

  @override
  void initState() {
    super.initState();
    _termsConditionRecognizer = TapGestureRecognizer()
      ..onTap = () {
        print("Terms and condition tapped");
      };
    _privacyPolicyRecognizer = TapGestureRecognizer()
      ..onTap = () {
        print("Provacy Policy tapped");
      };
  }

  @override
  Widget build(BuildContext context) {
    return Container(
      child: Center(
        child: RichText(
          text: TextSpan(
            text: 'By signing up you agree to the ',
            children: [
              TextSpan(
                text: 'Terms And Condition',
                recognizer: _termsConditionRecognizer,
              ),
              TextSpan(
                text: ' and ',
              ),
              TextSpan(
                text: 'Privacy Policy',
                recognizer: _privacyPolicyRecognizer,
              ),
            ],
          ),
        ),
      ),
    );
  }