JSFiddle - React, Tailwind, and code Playground
HTML
<div id="canvas">
<div id="dragme"></div>
</div>
CSS
#canvas {
width:500px;
height:250px;
border:1px solid #444;
zoom:0.9;
}
#dragme {
width:100px;
height:50px;
background:#f30;
}
JavaScript
var zoom = $('#canvas').css('zoom');
var canvasHeight = $('#canvas').height();
var canvasWidth = $('#canvas').width();
$('#dragme').draggable({
drag: function(evt,ui)
{
// zoom fix
ui.position.top = Math.round(ui.position.top / zoom);
ui.position.left = Math.round(ui.position.left / zoom);
// don't let draggable to get outside of the canvas
if (ui.position.left < 0)
ui.position.left = 0;
if (ui.position.left + $(this).width() > canvasWidth)
ui.position.left = canvasWidth - $(this).width();
if (ui.position.top < 0)
ui.position.top = 0;
if (ui.position.top + $(this).height() > canvasHeight)
ui.position.top = canvasHeight - $(this).height();
}
});