46 lines
965 B
Markdown
46 lines
965 B
Markdown
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# counter activity
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Display a number with a variable.
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### ~avatar avatar
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### @video td/videos/counter-0
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Welcome! This tutorial will teach you how to make a counter that increments when button A is pressed. Let's get started!
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### ~
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Let's start by creating a **local variable** `count` to keep track of the current count.
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```blocks
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let count = 0
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```
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The code under ``on button pressed("A")`` will run each time the user presses A. Let's add a line of code that increments `count` by `1`.
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```blocks
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let count = 0
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input.onButtonPressed(Button.A, () => {
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count = count + 1
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})
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```
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Since the count has changed, it's time to refresh the screen display. Let's add a line of code to display the count on screen.
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```blocks
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let count = 0
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input.onButtonPressed(Button.A, () => {
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count = count + 1
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basic.showNumber(count)
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})
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```
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### ~avatar avatar
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Excellent, you're ready to continue with the [challenges](/microbit/lessons/counter/challenges)
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### ~
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