91 lines
1.6 KiB
Markdown
91 lines
1.6 KiB
Markdown
# screen wipe blocks activity
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Clear the screen by pressing buttons on the micro:bit
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### ~avatar avatar
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### @video td/videos/screen-wipe-0
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This activity will teach how to clear the screen by pressing button A on the micro:bit.
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### ~
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You can use the clear screen` function to turn off all the LED on the screen. Let's illustrate this concept with a small script where the user has to press the button A to turn off the screen. Let's start by adding the code to show an animation.
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```blocks
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basic.showLeds(`
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# # # # #
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# # # # #
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. . . . .
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. . . . .
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. . . . .
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`)
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basic.showLeds(`
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# # # # #
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# # # # #
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# # # # #
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# # # # #
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. . . . .
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`)
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basic.showLeds(`
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. . . . .
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. . . . .
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# # # # #
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# # # # #
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. . . . .
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`)
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basic.showLeds(`
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. . . . .
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. . . . .
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. . . . .
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# # # # #
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# # # # #
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`)
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```
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We add another line of code that registers an *event handler* `on button pressed` *A* and calls `clear screen`.
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```blocks
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basic.showLeds(`
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# # # # #
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# # # # #
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. . . . .
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. . . . .
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. . . . .
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`)
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basic.showLeds(`
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# # # # #
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# # # # #
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# # # # #
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# # # # #
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. . . . .
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`)
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basic.showLeds(`
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. . . . .
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. . . . .
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# # # # #
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# # # # #
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. . . . .
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`)
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basic.showLeds(`
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. . . . .
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. . . . .
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. . . . .
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# # # # #
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# # # # #
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`)
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input.onButtonPressed(Button.A, () => {
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basic.clearScreen()
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})
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```
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*Run* the script in the simulator or on the micro:bit to see how this works!
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### ~avatar boothing
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Excellent, you're ready to continue with the [challenges](/lessons/screen-wipe/challenges)!
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### ~
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