pxt-calliope/docs/reference/js/lessons/counter/challenges.md

counter challenges

Coding challenges for the counter tutorial.

Before we get started

Complete the following guided tutorial At the end of the tutorial, your code should look like this:

let count = 0
input.onButtonPressed(Button.A, () => {
    count = count + 1
    basic.showNumber(count, 150)
})

Challenge 1

@video td/videos/counter-1-2

Let's add the code to count when B is pressed. Add an event handler with input->on button pressed(B) then add the code to count.

let count1 = 0
input.onButtonPressed(Button.A, () => {
    count1 = count1 + 1
    basic.showNumber(count1, 150)
})
input.onButtonPressed(Button.B, () => {
    count1 = count1 - 1 // ***
    basic.showNumber(count1, 150) // ***
}) // ***

Challenge 3

Now let's try to reset the counter when the BBC micro:bit is shaken. You will need to register an event handler with input->on shake.