Flutter In Action

Eric Windmill Foreword by Ray Rischpater MANNING Widget Lifecycles Stateless widget Stateful widget Constructor Constructor build() createState() Rebuilds when configuration changes Produces a state object State object (Mounted) initState() (Dirty state) widgetDidUpdate() When it receives new configuration build() (Clean state) dispose() setState() When internal state changes Flutter in Action ERIC WINDMILL FOREWORD BY RAY RISCHPATER MANNING SHELTER ISLAND For online information and ordering of this and other Manning books, please visit www.manning.com. The publisher offers discounts on this book when ordered in quantity. For more information, please contact Special Sales Department Manning Publications Co. 20 Baldwin Road PO Box 761 Shelter Island, NY 11964 Email: [email protected] ©2020 by Manning Publications Co. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by means electronic, mechanical, photocopying, or otherwise, without prior written permission of the publisher. Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in the book, and Manning Publications was aware of a trademark claim, the designations have been printed in initial caps or all caps. Recognizing the importance of preserving what has been written, it is Manning’s policy to have the books we publish printed on acid-free paper, and we exert our best efforts to that end. Recognizing also our responsibility to conserve the resources of our planet, Manning books are printed on paper that is at least 15 percent recycled and processed without the use of elemental chlorine. Acquisitions editor: Manning Publications Co. Development editor: 20 Baldwin Road Technical development editor: PO Box 761 Review editor: Shelter Island, NY 11964 Production editor: Copyeditor: Proofreader: Technical proofreader: Typesetter: Cover designer: ISBN 9781617296147 Printed in the United States of America Brian Sawyer Susanna Kline John Guthrie Aleks Dragosavljevic´ Anthony Calcara Tiffany Taylor and Frances Buran Melody Dolab Gonzalo Huerta-Cánepa Gordan Salinovic Marija Tudor brief contents PART 1 MEET FLUTTER ................................................................1 1 2 3 ■ ■ ■ Meet Flutter 3 A brief intro to Dart 24 Breaking into Flutter 54 PART 2 FLUTTER USER INTERACTION, STYLES, AND ANIMATIONS .........95 4 5 6 ■ ■ ■ Flutter UI: Important widgets, themes, and layout 97 User interaction: Forms and gestures 129 Pushing pixels: Flutter animations and using the canvas 158 PART 3 STATE MANAGEMENT AND ASYNCHRONOUS DART ........