JSFiddle - React, Tailwind, and code Playground

by 20yco

HTML

<div class="draggable"><div>drag me!</div><div>If you drag from here, it will jump at first</div></div>
<div class="draggable">you can drag me too, if you like</div>
<div class="draggable">hep hep</div>

<div id="guide-h" class="guide"></div>
<div id="guide-v" class="guide"></div>

CSS

body{
    font-family: courier new, courier; 
    font-size: 12px; 
}

.draggable{
    border: 1px solid #ccc; 
    display: inline-block; 
    cursor: move;
    position: absolute;         
}

.guide{
    display: none; 
    position: absolute; 
    left: 0; 
    top: 0; 
}

#guide-h{
    border-top: 1px dashed #55f; 
    width: 100%; 
}

#guide-v{
    border-left: 1px dashed #55f; 
    height: 100%; 
}

JavaScript

var MIN_DISTANCE = 5; // minimum distance to "snap" to a guide
var guides = []; // no guides available ... 
var innerOffsetX, innerOffsetY; // we'll use those during drag ... 

$( ".draggable" ).draggable({
    start: function( event, ui ) {
        guides = $.map( $( ".draggable" ).not( this ), computeGuidesForElement );
        innerOffsetX = event.originalEvent.offsetX;
        innerOffsetY = event.originalEvent.offsetY;
    }, 
    drag: function( event, ui ){
        // iterate all guides, remember the closest h and v guides
        var guideV, guideH, distV = MIN_DISTANCE+1, distH = MIN_DISTANCE+1, offsetV, offsetH; 
        var chosenGuides = { top: { dist: MIN_DISTANCE+1 }, left: { dist: MIN_DISTANCE+1 } }; 
        var $t = $(this); 
        var pos = { top: event.originalEvent.pageY - innerOffsetY, left: event.originalEvent.pageX - innerOffsetX }; 
        var w = $t.outerWidth() - 1; 
        var h = $t.outerHeight() - 1; 
        var elemGuides = computeGuidesForElement( null, pos, w, h ); 
        $.each( guides, function( i, guide ){
            $.each( elemGuides, function( i, elemGuide ){
                if( guide.type == elemGuide.type ){
                    var prop = guide.type == "h"? "top":"left"; 
                    var d = Math.abs( elemGuide[prop] - guide[prop] ); 
                    if( d < chosenGuides[prop].dist ){
                        chosenGuides[prop].dist = d; 
                        chosenGuides[prop].offset = elemGuide[prop] - pos[prop]; 
                        chosenGuides[prop].guide = guide; 
                    }
                }
            } ); 
        } );
        
        if( chosenGuides.top.dist <= MIN_DISTANCE ){
            $( "#guide-h" ).css( "top", chosenGuides.top.guide.top ).show(); 
            ui.position.top = chosenGuides.top.guide.top - chosenGuides.top.offset;
        }
        else{
            $( "#guide-h" ).hide(); 
            ui.position.top = pos.top; 
        }
        
        if(...