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web api instance method

MediaQueryList: addListener() method

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The deprecated addListener() method of the MediaQueryList interface adds a listener to the MediaQueryListener that will run a custom callback function in response to the media query status changing.

In older browsers MediaQueryList did not yet inherit from EventTarget, so this method was provided as an alias of addEventListener(). Use addEventListener() instead of addListener() if it is available in the browsers you need to support.

Syntax

addListener(func)

Parameters

  • func
    • : A function or function reference representing the callback function you want to run when the media query status changes.

Return value

None (undefined).

Examples

const paragraph = document.querySelector("p");
const mediaQueryList = window.matchMedia("(width <= 600px)");

function screenTest(e) {
  if (e.matches) {
    /* the viewport is 600 pixels wide or less */
    paragraph.textContent = "This is a narrow screen — 600px wide or less.";
    document.body.style.backgroundColor = "pink";
  } else {
    /* the viewport is more than 600 pixels wide */
    paragraph.textContent = "This is a wide screen — more than 600px wide.";
    document.body.style.backgroundColor = "aquamarine";
  }
}

mediaQueryList.addListener(screenTest);

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also