Cancel scrolling after user interaction

My webpage animates scrolling when users click on links to the same page. I want to cancel this a开发者_如何学编程nimation as soon as the user tries to scroll (otherwise the user and the browser are fighting for control) – no matter whether with the mouse wheel, the keyboard or the scrollbar (or any other way – are there other ways of scrolling?). I managed to cancel the animation after the mouse wheel or keyboard are used, how do I get this working with the scrollbar?

Here is how my code looks for the keyboard:

$(document.documentElement).keydown( function (event) {
    if(event.keyCode == 38 || 40) stopScroll();
});

function stopScroll() {
    $("html, body").stop(true, false);
}

I also tried a more elegant way of doing this by using scroll(), the problem is that scroll() catches everything including the animated and automated scrolling. I could not think of any way to let it catch all scrolling except the animated scrolling.

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you need animation marker, something like this

$("html, body").stop(true, false).prop('animatedMark',0.0).animate({scrollTop : top, animatedMark: '+=1.0'})

Here is the code, the code was mix of GWT and javascript so moved it to js, not fully tested, please try it

var lastAnimatedMark=0.0;
function scrollToThis(top){
    // Select/ stop any previous animation / reset the mark to 0 
    // and finally animate the scroll and the mark
    $("html, body").stop(true, false).prop('animatedMark',0.0).
    animate({scrollTop : top, animatedMark: '+=1.0'}
    ,10000,function(){
        //We finished , nothing just clear the data         
        lastAnimatedMark=0.0;
        $("html, body").prop('animatedMark',0.0);
    });
}
//Gets the animatedMark value
function animatedMark() {
    var x=$("html, body").prop('animatedMark');
    if (x==undefined){
        $("html, body").prop('animatedMark', 0.0);
    }
    x=$("html, body").prop('animatedMark');
    return x;
};

//Kills the animation
function stopBodyAnimation() {
    lastAnimatedMark=0;
    $("html, body").stop(true, false);
}
//This should be hooked to window scroll event 
function scrolled(){
    //get current mark
    var currentAnimatedMark=animatedMark();         
    //mark must be more than zero (jQuery animation is on) & but 
    //because last=current , this is user interaction.
    if (currentAnimatedMark>0 && (lastAnimatedMark==currentAnimatedMark)) {
        //During Animation but the marks are the same ! 
        stopBodyAnimation();
        return;
    }

    lastAnimatedMark=currentAnimatedMark;    
}

Here is the blog about it

http://alaamurad.com/blog/#!canceling-jquery-animation-after-user-interaction

Enjoy!

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Here's a jquery function that should do the trick:

function polite_scroll_to(val, duration, callback) {
    /* scrolls body to a value, without fighting the user if they
       try to scroll in the middle of the animation. */

    var auto_scroll = false;

    function stop_scroll() {
        if (!auto_scroll) {
            $("html, body").stop(true, false);
        }
    };
    $(window).on('scroll', stop_scroll);

    $("html, body").animate({
        scrollTop: val
    }, {
        duration: duration,
        step: function() {
            auto_scroll = true;
            $(window).one('scroll', function() {
                auto_scroll = false;
            });
        },
        complete: function() {
            callback && callback();
        },
        always: function() {
            $(window).off('scroll', stop_scroll);
        }
    });

};

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It's not very elegant, but you could use a flag of some kind to detect what type of scrolling you're dealing with (animated or 'manual') and always kill it when it's animated. Here's an untested example:

var animatedScroll = false;

// you probably have a method looking something like this:
function animatedScrollTo(top) {
  // set flag to true
  animatedScroll = true;
  $('html').animate({
    scrollTop : top
  }, 'slow', function() {
    // reset flag after animation is completed
    animatedScroll = false;
  });
} 

function stopScroll() {
  if (animatedScroll) {
    $("html, body").stop(true, false);
  }
}