HTMLCanvasElement: contextrestored event

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

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The contextrestored event of the Canvas API is fired if the user agent restores the backing storage for a CanvasRenderingContext2D.

You can redraw, re-retrieve resources, and reinitialize the state of your context after receiving this event.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("contextrestored", (event) => {});

oncontextrestored = (event) => {};

Event type

A generic Event.

Example

The code fragment below detects the context restored event.

const canvas = document.getElementById("canvas");

canvas.addEventListener(
  "contextrestored",
  (e) => {
    console.log(e);
    // call to redrawCanvas() or similar
  },
  false,
);

Specifications

Specification
HTML # event-contextrestored