Flutter App Development : How to Write for iOS and Android at Once

Worldwide Praise for Flutter App Development: How to Write for iOS and Android at Once
Table of Contents
About the Author
About the Technical Reviewer
Who Is This Book For?
Foreword
Preface
Chapter 1: Hello Flutter
	What Is Flutter?
	Why Flutter?
	The Other Options
	Native Solutions
	Conclusion
Chapter 2: Developing in Flutter
	The Flutter Toolchain
		The Flutter SDK
			Installing the Flutter SDK
		IDEs
			VS Code from Microsoft
			Android Studio/IntelliJ from JetBrains
			Which IDE Should I Use?
		IDE DevTools
		Emulators
			iOS Simulator
			Android Emulator
		Keeping the Tools Up to Date
			Flutter doctor
			Flutter Upgrade
	The Flutter Development Process
		Scaffolding the App and Files
		Anatomy of a Flutter Project
		Running Your App
		Running It As a Web App
		Running It on a Tethered Device
			Hot Reloading
			Debugging
	Conclusion
Chapter 3: Everything Is Widgets
	UI As Code
	Built-In Flutter Widgets
		Value Widgets
		Layout Widgets
		Navigation Widgets
		Other Widgets
	How to Create Your Own Stateless Widgets
	Widgets Have Keys
	Passing a Value into Your Widget
	Stateless and Stateful Widgets
		So Which One Should I Create?
	Conclusion
Chapter 4: Value Widgets
	The Text Widget
	The Icon Widget
	The Image Widget
		Embedded Images
		Network Images
		Sizing an Image
	SnackBar Widget
	Input Widgets
		Text Fields
			Making Your TextField Fancy
			Password Boxes
			Adjusting the Soft Keyboard
			Restricting the Data That Can Be Typed
		Checkboxes
		Radio Buttons
		Sliders
		Dropdowns
		Putting the Form Widgets Together
			Form Widget
			FormField Widget
				TextFormField and DropdownButtonFormField
				onSaved
				validator
				Submitting the Form
		One Big Form Example
	Conclusion
Chapter 5: Responding to Gestures
	Meet the Button Family
		ElevatedButton
		TextButton and IconButton
		FloatingActionButton (FAB)
		SegmentedButton
		CupertinoButton
	Dismissible
	Custom Gestures for Your Custom Widgets
		Step 1: Decide on Your Gestures and Behaviors
		Step 2: Create Your Custom Widget
		Step 3: Add a GestureDetector widget
		Step 4: Associate Your Gesture with Its Behavior
		Example 1: Reacting to a Long Press
		Example 2: Pinching to Add a New Item
		Example 3: Swiping Left or Right
	Conclusion
Chapter 6: Navigation and Routing
	Stack Navigation
		Navigating Forward and Back
		Using Anonymous Routes
		Get Result After a Scene Is Closed
	Drawer Navigation
		The Drawer Widget
		Filling the Drawer
	Tab Navigation
		DefaultTabController
		TabBarView
		TabBar and Tabs
		TabBar at the Bottom
	The Dialog Widget
		showDialog() and AlertDialog
		Responses with a Dialog
	Navigation Methods Can Be Combined
Chapter 7: Managing State
	What Is State?
	The Shape of a StatefulWidget
	The Most Important Rule About State!
	Passing State Down
	Lifting State Back Up
	An Example of State Management
	When Should We Use State?
	Conclusion
Chapter 8: State Management Libraries
	The InheritedWidget
	The BLoC Pattern
	Some Libraries
		ScopedModel
		Redux and Hooks
		Provider
		Whoa! That’s a Lot of Packages!
	Raw State
	Riverpod
		1. Install flutter_riverpod
		2. Wrap Your App with a ProviderScope
		3. Write a Provider
			Wait, What Is This Provider You Speak Of?
		4. Inherit from ConsumerStateWidget
		5. Read Data with ref.watch()
		6. Write Data with ref.read()
	Conclusion
Chapter 9: Making RESTful API Calls with HTTP
	What Is an API Call?
	The Flavors of API Requests
	Making an HTTP GET or DELETE Request
	Making an HTTP PUT, POST, or PATCH Request
	HTTP Responses to Widgets
		Brute Force – The Easy Way
		FutureBuilder – The Clean Way
		StreamBuilder
	Strongly Typed Classes
		Create a Business Class
		Write a .fromJSON() Method
		Use .fromJSON() to Hydrate the Object
	One Big Example
		Overview of the App
		Create the Flutter App
		Making a Strongly Typed Business Class
		list_people.dart
		A GET Request in Flutter
		A DELETE Request in Flutter
		upsert_person.dart
		A POST and PUT Request in Flutter
	Conclusion
Chapter 10: Styling with Themes
	Thinking in Flutter Styles
	Individual Styles
		Styling Text
	Mass-Changing Values
	Themes
		1. ColorScheme
		2. TextTheme
		3. Widget-Specific Themes
		4. Put Them Together in a Theme
		5. Override the Styles on Individual Widgets
	Final Styling Thoughts
		A Word About Colors
		Custom Fonts
	Conclusion
Chapter 11: Laying Out Your Widgets
	Our Approach
		1. Layout the Entire Screen (a.k.a. Scene)
		2. Position Widgets Above and Below Each Other or Side by Side
		3. Handle Situations When We Run Out of Space and Overflow the Scene
		4. Handle Extra Space in the Scene
		5. Make Finer Adjustments in Positioning
	Laying Out the Whole Scene
		MaterialApp Widget
		The Scaffold Widget
		The AppBar Widget
		SafeArea Widget
	Flutter’s Layout Algorithm
		The Dreaded “Unbounded Height” Error
	The Algorithm Itself
	Conclusion
Chapter 12: Layout – Positioning Widgets
	Putting Widgets Next to or Below Others
	Responsive Design
		Responsive Design in Flutter
		Flex and MediaQuery
	Conclusion
Chapter 13: Layout – Fixing Overflows
	Overflow Warning Bars
	Our Options to Correct Overflows
	A Sample Problem to Solve
	1. Allow the Children to Wrap
	2. Squeeze the Children Until They Fit
	3. Allow the User to Scroll
		SingleChildScrollView Widget
		The ListView Widget
			ListView Is Memory Efficient
			ListView Is Very Flexible
			Regular ListView
			ListView.builder: When You’re Building Widgets from a List of Objects
		GridView Widget
			GridView.extent()
			GridView.count()
	Conclusion
Chapter 14: Layout – Filling Extra Space
	What if There’s Extra Space Left Over?
	mainAxisAlignment
		crossAxisAlignment
		IntrinsicWidth
	Expanded Widget
		Open Space with Expandeds
	Conclusion
Chapter 15: Layout – Fine-Tuning Positioning
	Container Widget and the Box Model
	EdgeInsets for Padding and Margin
	Alignment and Positioning Within a Container
	Container Sizes Are Not Obvious
	Container Decorations
		Border
		BorderRadius
		BoxShape
	Conclusion
Chapter 16: Layout – Special Presentation Widgets
	Slivers
	Stack Widget
		Positioned Widget
		Card Widget
	The Table Widget
	Conclusion
Appendix A: Dart Language Overview
	What Is Dart?
	Expected Features – Dart Cheat Sheet
		Data Types
		Arrays/Lists
		Conditional Expressions
		Looping
		Classes
		Class Constructors
	Unexpected Things About Dart
		Type Inference
		final vs. const
		Null Safety
		String interpolationwith $
		Multiline Strings
		Spread Operator
		Map
		Functions Are Objects
		Big Arrow/Fat Arrow/Lambda
		Named Function Parameters
		Omitting “new” and “this.”
		Class Constructor Parameter Shorthand
		Private Class Members
		Mixins
		The Cascade Operator (..)
		No Overloading
		Named Constructors
Appendix B: Futures, Async, and Await
	Flutter Apps Use an Event Loop
	Why Would It Wait?
	How Do We Get the Data from a Future?
	Await
	Async
	Summary
Appendix C: Including Packages in Your Flutter App
	Finding a Library to Use
	Downloading the Library
	The pubspec.yaml File
	Using These Packages in Your Code
	Keeping Your Packages Current
	How to Upload Your Own Library
Appendix D: How to Work with Files
	Including a File with Your App
	Writing a File
	And Reading It!
	Using JSON
		Writing Your App’s Memory to JSON
		Reading JSON into Your App’s Memory
	Shared Preferences
		To Write Preferences
		To Read Preferences
	Conclusion
Appendix E: How to Debug Your Layout
Index