ng-resize

Manage resize events in Angular applications

Usage no npm install needed!

<script type="module">
  import ngResize from 'https://cdn.skypack.dev/ng-resize';
</script>

README

ngResize

Angular module for managing resize events in your applications. Some of goals of this project worth noting include:

  • Lightweight, flexible and easy to use
  • Bind resize event handler one time for entire app
  • Throttle window resize events

Usage

ngResize is composed of a provider, a service, and a directive. The service can be injected into other modules and used to programatically bind resize events in angular applications. The provider can be injected into your app's configuration phase to set things like throttle time.

Set ngResize as a dependency in your module:

var app = angular.module('YourApp', ['ngResize']);

Provider

app.config(function(resizeProvider) {

    // set throttle time
    resizeProvider.throttle = 100;

    // don't bind resize events on service initialization
    resizeProvider.initBind = false;

});

Properties

name description
throttle Throttle time for resize events, default is 32 (30 fps)
initBind Boolean to determine if we should bind resize event when service object is created, default is true

Service

app.directive('someDirective', function(resize) {
    return {
        controller: function($scope) {

        },
        link: function($scope, $elem, $attr, ctrl) {

            // on resize event, set dimensions
            // $event, and data arguments are available
            $scope.$on('resize', function($event, data) {
                $scope.width = data.width;
                $scope.height = data.height;
            });

        }
    };
});

The event listener callback accepts two arguments: $event, and data

Methods

name description
getThrottle() Returns current throttle time
setThrottle(integer) Sets current throttle time, applies to entire app
trigger([$scope]) $broadcast a resize event from specified $scope or $rootScope
bind() Bind resize event to $window, only useful if initBind = false or if event has been previously unbound
unbind() Unbinds resize even from $window

Directive

Something worth noting is that when the resize event is triggered, $timeout is used to debounce the expression to the end of the current $digest. This is to try and ensure that any costly calculations you might be doing won't interfere with the current $digest cycle. This approach was taken because resize events are often not critical functionality points, but necessary to maintain ui/ux stability. The goal is to provide efficient, useful access to resize events without crippling the ui.

<div ng-resize="setDimensions($event, data)"></div>

Two arguments are available to directive expressions: $event, and data

Roadmap

A few things I'm interested in pursuing with this project in the future are:

  • option to disable $rootScope $broadcast
  • ability to subscribe and unsubscribe $scopes from resize $broadcast
  • ability to bind resize events to $elements
  • manage detaching of $scopes and $elements when $destroyed
  • set unique throttle time for each $scope or $element