Scroll the page on drag with jQuery

℡╲_俬逩灬. 提交于 2019-11-27 18:32:58

You can do this quite simply by recording the position of the mouse when clicked, and the current position when being dragged. Try this:

var clicked = false, clickY;
$(document).on({
    'mousemove': function(e) {
        clicked && updateScrollPos(e);
    },
    'mousedown': function(e) {
        clicked = true;
        clickY = e.pageY;
    },
    'mouseup': function() {
        clicked = false;
        $('html').css('cursor', 'auto');
    }
});

var updateScrollPos = function(e) {
    $('html').css('cursor', 'row-resize');
    $(window).scrollTop($(window).scrollTop() + (clickY - e.pageY));
}

To prevent text selection while dragging, add the following CSS:

body {
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

Example fiddle


Update

Here's an version of the above as a jQuery plugin, extended to allow both vertical and horizontal scrolling via the settings. It also allows you to change the cursor that's used too.

(function($) {
  $.dragScroll = function(options) {
    var settings = $.extend({
      scrollVertical: true,
      scrollHorizontal: true,
      cursor: null
    }, options);

    var clicked = false,
      clickY, clickX;

    var getCursor = function() {
      if (settings.cursor) return settings.cursor;
      if (settings.scrollVertical && settings.scrollHorizontal) return 'move';
      if (settings.scrollVertical) return 'row-resize';
      if (settings.scrollHorizontal) return 'col-resize';
    }

    var updateScrollPos = function(e, el) {
      $('html').css('cursor', getCursor());
      var $el = $(el);
      settings.scrollVertical && $el.scrollTop($el.scrollTop() + (clickY - e.pageY));
      settings.scrollHorizontal && $el.scrollLeft($el.scrollLeft() + (clickX - e.pageX));
    }

    $(document).on({
      'mousemove': function(e) {
        clicked && updateScrollPos(e, this);
      },
      'mousedown': function(e) {
        clicked = true;
        clickY = e.pageY;
        clickX = e.pageX;
      },
      'mouseup': function() {
        clicked = false;
        $('html').css('cursor', 'auto');
      }
    });
  }
}(jQuery))

$.dragScroll();
/* Note: CSS is not relevant to the solution. 
   This is only needed for this demonstration */

body,
html {
  padding: 0;
  margin: 0;
}

div {
  height: 1000px;
  width: 2000px;
  border-bottom: 3px dashed #EEE;
  /* gradient is only to make the scroll movement more obvious */
  background: rgba(201, 2, 2, 1);
  background: -moz-linear-gradient(-125deg, rgba(201, 2, 2, 1) 0%, rgba(204, 0, 204, 1) 16%, rgba(94, 0, 201, 1) 31%, rgba(0, 153, 199, 1) 43%, rgba(0, 199, 119, 1) 56%, rgba(136, 199, 0, 1) 69%, rgba(199, 133, 0, 1) 83%, rgba(107, 0, 0, 1) 100%);
  background: -webkit-gradient(left top, right bottom, color-stop(0%, rgba(201, 2, 2, 1)), color-stop(16%, rgba(204, 0, 204, 1)), color-stop(31%, rgba(94, 0, 201, 1)), color-stop(43%, rgba(0, 153, 199, 1)), color-stop(56%, rgba(0, 199, 119, 1)), color-stop(69%, rgba(136, 199, 0, 1)), color-stop(83%, rgba(199, 133, 0, 1)), color-stop(100%, rgba(107, 0, 0, 1)));
  background: -webkit-linear-gradient(-125deg, rgba(201, 2, 2, 1) 0%, rgba(204, 0, 204, 1) 16%, rgba(94, 0, 201, 1) 31%, rgba(0, 153, 199, 1) 43%, rgba(0, 199, 119, 1) 56%, rgba(136, 199, 0, 1) 69%, rgba(199, 133, 0, 1) 83%, rgba(107, 0, 0, 1) 100%);
  background: -o-linear-gradient(-125deg, rgba(201, 2, 2, 1) 0%, rgba(204, 0, 204, 1) 16%, rgba(94, 0, 201, 1) 31%, rgba(0, 153, 199, 1) 43%, rgba(0, 199, 119, 1) 56%, rgba(136, 199, 0, 1) 69%, rgba(199, 133, 0, 1) 83%, rgba(107, 0, 0, 1) 100%);
  background: -ms-linear-gradient(-125deg, rgba(201, 2, 2, 1) 0%, rgba(204, 0, 204, 1) 16%, rgba(94, 0, 201, 1) 31%, rgba(0, 153, 199, 1) 43%, rgba(0, 199, 119, 1) 56%, rgba(136, 199, 0, 1) 69%, rgba(199, 133, 0, 1) 83%, rgba(107, 0, 0, 1) 100%);
  background: linear-gradient(-110deg, rgba(201, 2, 2, 1) 0%, rgba(204, 0, 204, 1) 16%, rgba(94, 0, 201, 1) 31%, rgba(0, 153, 199, 1) 43%, rgba(0, 199, 119, 1) 56%, rgba(136, 199, 0, 1) 69%, rgba(199, 133, 0, 1) 83%, rgba(107, 0, 0, 1) 100%);
  filter: progid: DXImageTransform.Microsoft.gradient( startColorstr='#c90202', endColorstr='#6b0000', GradientType=1);
  color: #EEE;
  padding: 20px;
  font-size: 2em;
}

body {
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  -khtml-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div>First...</div>

<div>Second...</div>

I just like to add. Using Rory's code I made horizontal scrolling.

var clicked = false, base = 0;

$('#someDiv').on({
    mousemove: function(e) {
        clicked && function(xAxis) {
            var _this = $(this);
            if(base > xAxis) {
                base = xAxis;
                _this.css('margin-left', '-=1px');
            }
            if(base < xAxis) {
                base = xAxis;
                _this.css('margin-left', '+=1px');
            }
        }.call($(this), e.pageX);
    },
    mousedown: function(e) {
        clicked = true;
        base = e.pageX;
    },
    mouseup: function(e) {
        clicked = false;
        base = 0;
    }
});

This code will work on horizontal and vertical mouse drag scroll. It's pretty simple.

var curYPos = 0,
    curXPos = 0,
    curDown = false;

window.addEventListener('mousemove', function(e){ 
  if(curDown === true){
    window.scrollTo(document.body.scrollLeft + (curXPos - e.pageX), document.body.scrollTop + (curYPos - e.pageY));
  }
});

window.addEventListener('mousedown', function(e){ curDown = true; curYPos = e.pageY; curXPos = e.pageX; });
window.addEventListener('mouseup', function(e){ curDown = false; }); 

Based on the first answer, this is the code for horizontal scroll on mouse drag:

var clicked = false, clickX;
$(document).on({
    'mousemove': function(e) {
        clicked && updateScrollPos(e);
    },
    'mousedown': function(e) {
        e.preventDefault();        
        clicked = true;
        clickX = e.pageX;
    },
    'mouseup': function() {
        clicked = false;
        $('html').css('cursor', 'auto');
    }
});

var updateScrollPos = function(e) {
    $('html').css('cursor', 'grabbing');
    $(window).scrollLeft($(window).scrollLeft() + (clickX - e.pageX));
}

Base on Rory McCrossan's idea, implemented with AngularJS2.

import {Directive, ElementRef, OnDestroy, Input} from "@angular/core";

declare var jQuery: any;

@Directive({
    selector: '[appDragScroll]'
})
export class DragScrollDirective implements OnDestroy {

    @Input() scrollVertical: boolean = true;
    @Input() scrollHorizontal: boolean = true;

    private dragging = false;
    private originalMousePositionX: number;
    private originalMousePositionY: number;
    private originalScrollLeft: number;
    private originalScrollTop: number;

    constructor(private nodeRef: ElementRef) {
        let self = this;

        jQuery(document).on({
            "mousemove": function (e) {
                self.dragging && self.updateScrollPos(e);
            },
            "mousedown": function (e) {
                self.originalMousePositionX = e.pageX;
                self.originalMousePositionY = e.pageY;
                self.originalScrollLeft = jQuery(self.nodeRef.nativeElement).scrollLeft();
                self.originalScrollTop = jQuery(self.nodeRef.nativeElement).scrollTop();
                self.dragging = true;
            },
            "mouseup": function (e) {
                jQuery('html').css('cursor', 'auto');
                self.dragging = false;
            }
        });

    }

    ngOnDestroy(): void {
        jQuery(document).off("mousemove");
        jQuery(document).off("mousedown");
        jQuery(document).off("mouseup");
    }

    private updateScrollPos(e) {
        jQuery('html').css('cursor', this.getCursor());

        let $el = jQuery(this.nodeRef.nativeElement);
        if (this.scrollHorizontal) {
            $el.scrollLeft(this.originalScrollLeft + (this.originalMousePositionX - e.pageX));
        }
        if (this.scrollVertical) {
            $el.scrollTop(this.originalScrollTop + (this.originalMousePositionY - e.pageY));
        }
    }

    private getCursor() {
        if (this.scrollVertical && this.scrollHorizontal) return 'move';
        if (this.scrollVertical) return 'row-resize';
        if (this.scrollHorizontal) return 'col-resize';
    }

}

I modified Rory's code quite a bit, and I got per-element side scrolling to work. I needed that for a project that had multiple scrollable tiles in a single view for a webapp. Add the .drag class to any element, possibly do a bit of styling, and it should be good to go.

// jQuery sidescroll code. Can easily be modified for vertical scrolling as well.
// This code was hacked together so clean it up if you use it in prod.
// Written by Josh Moore
// Thanks to Rory McCrossan for a good starting point

// How far away the mouse should move on a drag before interrupting click
// events (your own code must also interrupt regular click events with a
// method that calls getAllowClick())
const THRESHOLD = 32;
var clicked = false;
var allowClick = true;

// mouseX: most recent mouse position. updates when mouse moves.
//     el: jQuery element that will be scrolled.
//    thX: "threshold X", where the mouse was at the beginning of the drag
var mouseX, startY, el, thX;

// Add the .drag class to any element that should be scrollable.
// You may need to also add these CSS rules:
//   overflow: hidden; /* can be replaced with overflow-x or overflow-y */
//   whitespace: none;
function drag() {
    $('.drag').on({
        'mousemove': e => {
            if (el != null && clicked) {
                el.scrollLeft(el.scrollLeft() + (mouseX - e.pageX));
                mouseX = e.pageX;
                allowClick = Math.abs(thX - mouseX) > THRESHOLD ? false : true;
            }
        },
        'mousedown': e => {
            clicked = true;
            // This lets the user click child elements of the scrollable.
            // Without it, you must click the .drag element directly to be able to scroll.
            el = $(e.target).closest('.drag');
            mouseX = e.pageX;
            thX = e.pageX;
        },
        'mouseup': e => {
            clicked = false;
            el = null;
            allowClick = true;
        }
    });
}

function getAllowClick() {
    return allowClick;
}

Again, I had no use for vertical scrolling but it would be pretty simple to add (replace X's with Y's, scrollTop() instead of scrollLeft(), etc). Hope this helps someone in the future!

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