jQuery .scrollTop(); + animation

问题

I set the page to scroll to top when a button is clicked. But first I used an if statement to see if the top of the page was not set to 0. Then if it's not 0 I animate the page to scroll to the top.

var body = $("body");
var top = body.scrollTop() // Get position of the body

if(top!=0)
{
  body.animate({scrollTop:0}, '500');
}

The tricky part now is animating something AFTER the page has scrolled to the top. So my next thought is, find out what the page position is. So I used console log to find out.

console.log(top);  // the result was 365

This gave me a result of 365, I'm guessing that is the position number I was at just before scrolling to the top.

My question is how do I set the position to be 0, so that I can add another animation that runs once the page is at 0?

Thanks!

回答1:

To do this, you can set a callback function for the animate command which will execute after the scroll animation has finished.

For example:

var body = $("html, body");
body.stop().animate({scrollTop:0}, 500, 'swing', function() { 
   alert("Finished animating");
});

Where that alert code is, you can execute more javascript to add in further animation.

Also, the 'swing' is there to set the easing. Check out http://api.jquery.com/animate/ for more info.

回答2:

Try this code:

$('.Classname').click(function(){
    $("html, body").animate({ scrollTop: 0 }, 600);
    return false;
});

回答3:

Use this:

$('a[href^="#"]').on('click', function(event) {

    var target = $( $(this).attr('href') );

    if( target.length ) {
        event.preventDefault();
        $('html, body').animate({
            scrollTop: target.offset().top
        }, 500);
    }

});

回答4:

Try this instead:

var body = $("body, html");
var top = body.scrollTop() // Get position of the body
if(top!=0)
{
       body.animate({scrollTop :0}, 500,function(){
         //DO SOMETHING AFTER SCROLL ANIMATION COMPLETED
          alert('Hello');
      });
}

回答5:

for this you can use callback method

body.animate({
      scrollTop:0
    }, 500, 
    function(){} // callback method use this space how you like
);

回答6:

Simple solution:

scrolling to any element by ID or NAME:

SmoothScrollTo("#elementId", 1000);

code:

function SmoothScrollTo(id_or_Name, timelength){
    var timelength = timelength || 1000;
    $('html, body').animate({
        scrollTop: $(id_or_Name).offset().top-70
    }, timelength, function(){
        window.location.hash = id_or_Name;
    });
}

回答7:

Code with click function()

    var body = $('html, body');

    $('.toTop').click(function(e){
        e.preventDefault();
        body.animate({scrollTop:0}, 500, 'swing');

}); 

.toTop = class of clicked element maybe img or a

回答8:

jQuery("html,body").animate({scrollTop: jQuery("#your-elemm-id-where you want to scroll").offset().top-<some-number>}, 500, 'swing', function() { 
       alert("Finished animating");
    });

回答9:

you must see this

$(function () {
        $('a[href*="#"]:not([href="#"])').click(function () {
            if (location.pathname.replace(/^\//, '') == this.pathname.replace(/^\//, '') && location.hostname == this.hostname) {
                var target = $(this.hash);
                target = target.length ? target : $('[name=' + this.hash.slice(1) + ']');
                if (target.length) {
                    $('html, body').animate({
                        scrollTop: target.offset().top
                    }, 1000);
                    return false;
                }
            }
        });
    });

or try them

$(function () {$('a').click(function () {
$('body,html').animate({
    scrollTop: 0
}, 600);
return false;});});

来源：https://stackoverflow.com/questions/16475198/jquery-scrolltop-animation