Year 8 - App Development 1

• Computer Science
• Lower Secondary (Key Stage 3)

Y8 - Unit 6 - App Development

Lesson 1: App for that

Key Vocabulary:

Decompose

In this lesson, you will

• Identify when a problem needs to be broken down
  
• Implement and customise GUI elements to meet the needs of the user
  

What is your ‘app for that’?

You have five minutes to work in pairs.

  

Think of an idea for an app that could have a positive impact on the world.

Think about how the user will interact with the app.

Write your ideas on a the next slide.

What is your
‘app for that’?

The Tappy Tap App

Over the next two and half lessons we will develop a new app called the Tappy Tap App. 

It will:

• Get users to click a moving blue dot as many times as they can within a time limit
• Give the user a point for each accurate click on the blue dot
• Move the blue dot each time it is clicked

Decompose the problem

Decomposition is breaking a problem down into more manageable chunks.

Programming an app for a mobile device can be a daunting task to undertake.

Decomposing the problem helps us make the task less daunting and more achievable.

Decompose the problem

Imagine that your job is to make the first level of a new platform game.

You might start by decomposing the problem in the following way:

• Create the layout of the level
• Add a user-controlled character
• Add enemies
• Add score, timer, and power-ups

Continue decomposing

When you arrive at each decomposed step, you can now decompose it further.

How might you decompose the ‘player movement’ step further?

• Add left and right movement
• Add a gravity effect
• Add the ability to jump

Success criteria

Welcome screen:

• Must show logo and instructions on how to play
  
• Must have a button that activates the game play once clicked
  

Game play:

• The game must last 15 seconds before automatically moving to the final score screen
  
• There must be a blue dot and a red dot that the user can press
  
• When the blue dot is pressed, the score must increase by one
  
• When the blue dot is pressed, the dot should move to a different place on the screen
  
• The red dot must also move to a different place on the screen when pressed, but the score will decrease by one
  

Final score:

• Must display the user’s score at the end of the game
  
• Must have a button to allow the user to return to the welcome screen
  

Decompose the 'Tappy Tap App'

Look at the requirements of the Tappy Tap App on your worksheet.

How would you decompose the problem?

Think/write/pair/share.

How did you decompose the problem?

App Lab demonstration

Log into App Lab using the login details given to you:

> go to code.org

> Create account 

> I'm a student 

> Sign up with Microsoft

> Enter the class code (will be given to you)

• Browse to ‘Start a new project’
• Select App Lab
• Rename your project ‘Tappy Tap App’
• Add a button to the screen

Design the home screen

Your task is to implement the design of the welcome screen (don’t forget to rename ‘screen1’ as ‘welcome screen’). Use your success criteria to help, as well as the sketched design on the right.

Explorer tasks:

• Add a new game screen
• Watch the following video (ncce.io/AppLabA4)
• Code the button to open the game screen

Play your future Tappy Tap App

Visit the following URL to play the game:

ncce.io/TappyTapAppL1

After a couple of goes, look at your success criteria and ask yourself whether or not the game meets all the criteria.