a93febb5b7
* add image and deprecated arrow functions * update locales * map basic.showArrow * map arrow blocks * map & remove arrow images * remove arrow blocks * update locales * remove & patch: rgbw -> rgb button/pin pressed -> button/pin event loudness -> soundLevel * update ts mappings for arrows * add wip ts patch rules * update .blocks files * use Click instead of Down as default in Documentation and tests * patch test.blocks * fix lowercase name tag * update test.blocks * update blocks test files * update blocks test files * format block files * pass blocks file tests * fix ts mapping * fix color.defl value closes https://github.com/microsoft/pxt-calliope/issues/136 * fix ts mappings - add optional spacing at the end of rgbw() - map up to v4.0.19 * add suggested changes * replace innerText by textContent Co-authored-by: JW <gitkraken@juriwolf.de> Co-authored-by: Juri <info@juriwolf.de>
55 lines
1.7 KiB
Markdown
55 lines
1.7 KiB
Markdown
# On Button Pressed
|
|
|
|
Start an [event handler](/reference/event-handler) (part of the program that will run when something happens, like when a button is pressed).
|
|
This handler works when button `A` or `B` is pressed, or `A` and `B` together.
|
|
When you are using this function in a web browser, click the buttons on the screen instead of the ones
|
|
on the @boardname@.
|
|
|
|
* For button `A` or `B`: This handler works when the button is pushed down and released within 1 second.
|
|
* For `A` and `B` together: This handler works when `A` and `B` are both pushed down, then one of them is released within 1.5 seconds of pushing down the second button.
|
|
|
|
```sig
|
|
input.onButtonEvent(Button.A, ButtonEvent.Click, () => {})
|
|
```
|
|
|
|
Find out how buttons provide input to the @boardname@ in this video:
|
|
|
|
https://www.youtube.com/watch?v=t_Qujjd_38o
|
|
|
|
## Example: count button clicks
|
|
|
|
This example counts how many times you press the `A` button.
|
|
Each time you press the button, the [LED screen](/device/screen) shows the `count` variable getting bigger.
|
|
|
|
```blocks
|
|
let count = 0
|
|
basic.showNumber(count)
|
|
input.onButtonEvent(Button.A, ButtonEvent.Click, () => {
|
|
count++;
|
|
basic.showNumber(count);
|
|
})
|
|
```
|
|
|
|
## Example: roll dice
|
|
|
|
This example shows a number from 1 to 6 when you press the `B` button.
|
|
|
|
```blocks
|
|
input.onButtonEvent(Button.B, ButtonEvent.Click, () => {
|
|
let dice = randint(0, 5) + 1
|
|
basic.showNumber(dice)
|
|
})
|
|
```
|
|
|
|
## ~hint
|
|
|
|
This program adds a `1` to `random(5)` so the numbers on the dice will come out right.
|
|
Otherwise, sometimes they would show a `0`.
|
|
|
|
## ~
|
|
|
|
## See also
|
|
|
|
[button is pressed](/reference/input/button-is-pressed), [forever](/reference/basic/forever), [random](/blocks/math)
|
|
|