Question

While designing an app that should follow the Material Design Guidelines, we’ll want to add the ripple animation to Widgets when tapped.

Flutter provides the InkWell Widget to achieve this effect.

Directions

1. Create a Widget we want to tap
2. Wrap it in an InkWell Widget to manage tap callbacks and ripple animations

// The InkWell Wraps our custom flat button Widget
InkWell(
  // When the user taps the button, show a snackbar
  onTap: () {
    Scaffold.of(context).showSnackBar(SnackBar(
      content: Text('Tap'),
    ));
  },
  child: Container(
    padding: EdgeInsets.all(12.0),
    child: Text('Flat Button'),
  ),
);

Complete example

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final title = 'InkWell Demo';

    return MaterialApp(
      title: title,
      home: MyHomePage(title: title),
    );
  }
}

class MyHomePage extends StatelessWidget {
  final String title;

  MyHomePage({Key key, this.title}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(title),
      ),
      body: Center(child: MyButton()),
    );
  }
}

class MyButton extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    // The InkWell Wraps our custom flat button Widget
    return InkWell(
      // When the user taps the button, show a snackbar
      onTap: () {
        Scaffold.of(context).showSnackBar(SnackBar(
          content: Text('Tap'),
        ));
      },
      child: Container(
        padding: EdgeInsets.all(12.0),
        child: Text('Flat Button'),
      ),
    );
  }
}