AngularJS - $anchorScroll smooth/duration

Question

Reading the AngularJS docs I haven\'t figured out if $anchorScroll can have a duration/easing option to smooth scroll to elements.

It only says:

Answer 1

None of the solutions here actually does what OP originally asked, that is, make $anchorScroll scrolling smoothly. Difference between smooth scrolling directives and $anchroScroll is that it uses/modifies $location.hash(), which may be desirable in some cases.

Here is gist for simple module that replaces $anchorScroll scrolling with smooth scrolling. It uses https://github.com/oblador/angular-scroll library for the scrolling itself (replace it with something else if you want, it should be easy).

https://gist.github.com/mdvorak/fc8b531d3e082f3fdaa9
Note: It actually does not get $anchorScroll to scroll smoothly, but it replaces its handler for scrolling.

Enable it simply by referencing mdvorakSmoothScroll module in your application.

Answer 2

I am not aware of how to animate $anchorScroll . Here's how I do it in my projects:

/* Scroll to top on each ui-router state change */
$rootScope.$on('$stateChangeStart', function() {
 scrollToTop();
});

And the JS function:

function scrollToTop() {
    if (typeof jQuery == 'undefined') {
        return window.scrollTo(0,0);
    } else {
        var body = $('html, body');
        body.animate({scrollTop:0}, '600', 'swing');
    }
    log("scrollToTop");
    return true;
}

Answer 3

Alan, thank you. If anyone interested, I formatted it based on John Pappa standards.

(function() {

'use strict';
var moduleId = 'common';
var serviceId = 'anchorSmoothScroll';

angular
    .module(moduleId)
    .service(serviceId, anchorSmoothScroll);

anchorSmoothScroll.$inject = ['$document', '$window'];

function anchorSmoothScroll($document, $window) {

    var document = $document[0];
    var window = $window;

    var service = {
        scrollDown: scrollDown,
        scrollUp: scrollUp,
        scrollTo: scrollTo,
        scrollToTop: scrollToTop
    };
    return service;

    function getCurrentPagePosition(currentWindow, doc) {
        // Firefox, Chrome, Opera, Safari
        if (currentWindow.pageYOffset) return currentWindow.pageYOffset;
        // Internet Explorer 6 - standards mode
        if (doc.documentElement && doc.documentElement.scrollTop)
            return doc.documentElement.scrollTop;
        // Internet Explorer 6, 7 and 8
        if (doc.body.scrollTop) return doc.body.scrollTop;
        return 0;
    }

    function getElementY(doc, element) {
        var y = element.offsetTop;
        var node = element;
        while (node.offsetParent && node.offsetParent !== doc.body) {
            node = node.offsetParent;
            y += node.offsetTop;
        }
        return y;
    }

    function scrollDown(startY, stopY, speed, distance) {

        var timer = 0;

        var step = Math.round(distance / 25);
        var leapY = startY + step;

        for (var i = startY; i < stopY; i += step) {
            setTimeout('window.scrollTo(0, ' + leapY + ')', timer * speed);
            leapY += step;
            if (leapY > stopY) leapY = stopY;
            timer++;
        }
    };

    function scrollUp(startY, stopY, speed, distance) {

        var timer = 0;

        var step = Math.round(distance / 25);
        var leapY = startY - step;

        for (var i = startY; i > stopY; i -= step) {
            setTimeout('window.scrollTo(0, ' + leapY + ')', timer * speed);
            leapY -= step;
            if (leapY < stopY) leapY = stopY;
            timer++;
        }
    };

    function scrollToTop(stopY) {
        scrollTo(0, stopY);
    };

    function scrollTo(elementId, speed) {

        var element = document.getElementById(elementId);

        if (element) {
            var startY = getCurrentPagePosition(window, document);
            var stopY = getElementY(document, element);

            var distance = stopY > startY ? stopY - startY : startY - stopY;

            if (distance < 100) {
                this.scrollToTop(stopY);

            } else {

                var defaultSpeed = Math.round(distance / 100);
                speed = speed || (defaultSpeed > 20 ? 20 : defaultSpeed);

                if (stopY > startY) {
                    this.scrollDown(startY, stopY, speed, distance);
                } else {
                    this.scrollUp(startY, stopY, speed, distance);
                }
            }

        }

    };

};

})();

Answer 4

You can also use the angular-scroll, link "https://github.com/durated/angular-scroll/". It is smooth scrolling also few easing functions to get a professional look.

Answer 5

Unfortunately this is not possible using $anchorScroll. As you discovered $anchorScroll doesn't have any options and doesn't work with $ngAnimate. In order to animate the scroll you would need to use your own service/factory or just straight javascript.

For the sake of self-learning I put together an example with a smooth scrolling service. There are probably better ways to do this so any feedback is encouraged.

To scroll to an element you attach a ng-click="gotoElement(ID)" to any element. I think an even better route would be to make this a directive.

Here's the working example on jsFiddle.

Update

There are now a number of third-party directives for accomplishing this.

• https://github.com/oblador/angular-scroll.
• https://github.com/d-oliveros/ngSmoothScroll
• https://github.com/arnaudbreton/angular-smoothscroll
• https://gist.github.com/justinmc/d72f38339e0c654437a2

Answer 6

You can also use ngSmoothScroll, link: https://github.com/d-oliveros/ngSmoothScroll.

Just include the smoothScroll module as a dependency and use it like this:

<a href="#" scroll-to="my-element-3">Click me!</a>