pxt-calliope/docs/blocks/on-start.md
Peli de Halleux 92b60a251d On start support (#324)
* annotating APIs to support onstart

* missed file

* updated templates

* adding new lines in main.ts

* fixing docs

* removing onstart

* updated docs

* updated various docs

* more docs

* adding upgrade policies for blocks

* updated pxt reference

* placing on start under "basic"
2016-12-19 14:09:35 -08:00

570 B

On Start

An event that runs when the program starts.

The on start is a special event that runs when the program starts, before any other event. Use this event to initialize your program.

Example

In this example, on start sets a dimmer brightness on the screen and the button handler shows a string.

input.onButtonPressed(Button.A, () => {
    basic.showString("Hello!")
})
led.setBrightness(50)

What about JavaScript?

on-start only exists in the block editor. In JavaScript, all code executes sequentially from the first line.