Breakpoint Listener

Creates a listener that triggers actions when the viewport reaches specified breakpoint. This function helps implement responsive behavior dynamically in the application.

Usage

Use getBreakpointListener to respond to changes in screen width, such as adjusting layouts, toggling visibility, or modifying component behavior. Avoid excessive listeners that could impact performance. Combine with clear responsive design patterns to maintain usability across devices.

API Reference

Arguments

Argument	Type	Required	Description
handler	function	true	Handler function that will be called when the breakpoint threshold has been met*. Called immediately after initialization.
breakpoint	integer|string	false	The desired breakpoint. If a number is given, it will be treated as pixels. By default, it's 768px.
topFrame	boolean	false	By default, the listener measures the current frame. This attaches it to the topmost frame instead, falling back to the current frame when that frame belongs to another origin.

Threshold event

The handler function is invoked only when the window width crosses the specified breakpoint, either becoming narrower or wider, rather than on every resize event. A boolean value is passed as the first argument, indicating the direction of the change.

Returns

Object

Property	Type	Description
remove	function	Use this function to remove the event listener when it's no longer needed.

Examples

In plain JS

const breakpointListener = Harmonia.getBreakpointListener((matches) => {
  if (matches) {
    console.log('Window is either equal or smaller then the breakpoint');
  } else {
    console.log('Window is bigger then the breakpoint');
  }
}, 1184);

// When no longer needed
breakpointListener.remove();

In a module

import { getBreakpointListener } from '@codbex/harmonia';

const breakpointListener = getBreakpointListener((matches) => {
  if (matches) {
    console.log('Window is either equal or smaller then the breakpoint');
  } else {
    console.log('Window is bigger then the breakpoint');
  }
}, 1184);

// When no longer needed
breakpointListener.remove();