Hello App Inventor! : Android programming for kids and the rest of us

544 Pages·2014·18.54 MB·English

by  Beer

Hello App Inventor!: Android
programming for kids and the rest of
us
Paula Beer and Carl Simmons
Copyright
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Dedication
To anyone who really, really tries. Come on, keep going, you’re nearly
there.
P.B.
To Frank, who treated us like geniuses and loved us fiercely.
C.S.
Brief Table of Contents
Copyright
Brief Table of Contents
Table of Contents
Preface
Acknowledgments
About this book
Chapter 1. Getting to know App Inventor
Chapter 2. Designing the user interface
Chapter 3. Using the screen: layouts and the canvas
Chapter 4. Fling, touch, and drag: user interaction with the touch screen
Chapter 5. Variables, decisions, and procedures
Chapter 6. Lists and loops
Chapter 7. Clocks and timers
Chapter 8. Animation
Chapter 9. Position sensors
Chapter 10. Barcodes and scanners
Chapter 11. Using speech and storing data on your phone
Chapter 12. Web-enabled apps
Chapter 13. Location-aware apps
Chapter 14. From idea to app
Chapter 15. Publishing and beyond
Index
Table of Contents
Copyright
Brief Table of Contents
Table of Contents
Preface
Acknowledgments
About this book
Chapter 1. Getting to know App Inventor
First a little history ...
What can an Android smartphone do?
App Inventor setup
Option 1: Using Wi-Fi with the App Inventor companion phone
software
Option 2: using the onscreen emulator
Option 3: connecting via USB cable
Using all three options
Troubleshooting
The App Inventor juggling act
1. Designing the app screen
2. Telling the app what to do
3. Testing the program
How will it look? App Inventor Designer
Component properties
How will it work? The Blocks Editor
Built-in blocks
Component-specific blocks
Running and testing programs
Running and testing: emulator vs. smartphone
Your first app: Hello World!
1. Opening App Inventor
2. Starting with a new project
3. Adding a Notifier component to the project
4. Writing the program using blocks
5. Testing the app
Computers never sleep: why you use events
Saving in the cloud and using checkpoints
Button click: Hello World! app, version 2
1. Saving a new copy of Hello World!
2. Adding a Button component
3. Programming the blocks
4. Testing your app
Taking it further
Packaging an app for your phone
Downloading APKs directly to your phone or computer
Downloading APKs as files to your computer
Changing the app’s icon
What did you learn?
Test your knowledge
Try it out
Chapter 2. Designing the user interface
What is a user interface?
Using the Designer to make a UI
Speeding along: built-in components
Getting to Know Ewe app
1. Setting up the project
2. Adding a sheep image
3. Adding a “baa!” sound
4. Programming the blocks, part 1: playing the sound
5. Programming the blocks, part 2: vibrating the phone
Extra challenge: Ewe Scared Her! app
1. Saving a new project
2. Adding components: accelerometer, reset button, and screen
arrangement
3. Arranging the screen
4. Programming the blocks
Taking it further
What did you learn?
Test your knowledge
Try it out
Chapter 3. Using the screen: layouts and the canvas
Layout
Layout: mini-project
Spooky Sound FX app
1. Setting the screen properties: alignment, orientation, and
scrolling
2. Setting up the table arrangement and eight buttons
3. Adding the eight Sound components and their source files
4. Coding the blocks
Taking it further
Introducing the Canvas component
Graffiti Artist app
1. Setting up the user interface
2. Coding the blocks
What did you learn?
Test your knowledge
Try it out
Chapter 4. Fling, touch, and drag: user interaction with the touch screen
Events up close
Flung event
Drag event
Flingflung app
1. Dragging out the Ball1.Flung event handler from the Ball1
drawer
2. Giving the ball velocity
3. Enabling the Dragged event
4. Enabling the CollidedWith event
Fling It! app
1. Making the touch sprite react to the user touching the sprite
2. Making the drag sprite react to the user dragging the sprite
3. Making the fling sprite react to the user flinging the sprite
4. Playing the soundtrack
5. Stopping the soundtrack
Taking it further
What did you learn?
Test your knowledge
Try it out
Chapter 5. Variables, decisions, and procedures
Remembering useful things
Total recall: naming and retrieving variables
Flattery app
1. Setting up the screen
2. Coding the blocks: creating a UsersName variable
3. Getting and storing UsersName
4. Revealing the buttons
5. Stringing it all together: making the flattery messages
Taking it further
Decisions, decisions: using variables to choose an action
Comparison operators
How can a dumb machine make a decision?
Prankster Flattery app (Personality Judge app)
1. Setting up the app
2. Coding the if ... else blocks
Using creative comparison conditions
Taking it further
Keeping track with comments
Changing variables
Dice Roll app
1. Programming the blocks
2. Taking it further
Guess What I Am Thinking app
1. Setting up the screen