JSFiddle - React, Tailwind, and code Playground

by Lindsey Suarez

HTML

<div class="box">
    <div class="item">Test1</div>
    <div class="item">Test2</div>
    <div class="item">Test3</div>
    <div class="item">Test4</div>
    <div class="item">Test5</div>
    <div class="item">Test6</div>
    <div class="item">Test7</div>
    <div class="item">Test8</div>
    <div class="item">Test9</div>
    <div class="item">Test10</div>
    <div class="item">Test11</div>
    <div class="item">Test12</div>
    <div class="item">Test13</div>
    <div class="item">Test14</div>
    <div class="item">Test15</div>
    <div class="item">Test16</div>
    <div class="item">Test17</div>
    <div class="item">Test18</div>
    <div class="item">Test19</div>
    <div class="item">Test20</div>
    <div class="item">Test21</div>
    <div class="item">Test22</div>
    <div class="item">Test23</div>
    <div class="item">Test24</div>
    <div class="item">Test25</div>
    <div class="item">Test26</div>
    <div class="item">Test27</div>
    <div class="item">Test28</div>
</div>

<div id="draggable">Drag Me!</div>

CSS

.box {
    height:250px;
    width:200px;
    overflow-x:hidden;
    overflow-y:auto;
    border:1px solid #000000;
    margin-top: 50px;
}

.item {
    border:1px solid #ff0000;
    height:30px;
}

#draggable {
    border:2px solid #00ff00;
    height:20px;
    width:100px;    
}

.ui-state-default {
    background-color:#aaaaaa;
}

.ui-state-hover {
    background-color:#eeeeee;
}

JavaScript

$('.item').droppable( {
    activeClass: "ui-state-default",
    hoverClass: "ui-state-hover",
    accept: "#draggable",
    drop: function( event, ui ) {
        var cTop = $(this).parent().position().top + parseInt($(this).parent().css("margin-top"));
        var cBtm = $(this).parent().position().top + parseInt($(this).parent().css("margin-top")) + $(this).parent().height();
        var dTop = $(this).position().top + parseInt($(this).css("margin-top"));
        var dBtm = $(this).position().top + parseInt($(this).css("margin-top")) + $(this).height()
        
        if (dBtm > cTop && dTop < cBtm) {
            alert("Dropped.");
        }
    }
});

$('#draggable').draggable({
    helper: 'clone',
    revert: 'invalid',
    start: function( event, ui ) {
        // disable the ability to select text.
        // this is a hack for chrome and safari.
        document.onselectstart = function () { return false; };
    },
    stop: function ( event, ui ) {
        document.onselectstart = null;
    }
});