Disable longPress action on mobile with javascript

Question

in this period,I make some new webApps, but I have a big problem with drag and drop. I write a file manager in javascript, but when on mobile (smartphone, tablet andorid or iOs) I try to work drag and drop, the phone show me the longPress menu (on folder icon for examample) for copy url or image. there is some way in JS to disable longPress on mobile?

load image via css, isn't a valid solutions for me.

Answer 1

-webkit-touch-callout: none;                /* prevent callout to copy image, etc when tap to hold */
    -webkit-user-select: none;                  /* prevent copy paste, to allow, change 'none' to 'text' */

Answer 2

check the value of navigator.userAgent and compare with android|iphone|ipad etc and in your java script you could do the following

function init() {
  onLongPress(document.getElementById('element'));
}

function onLongPress(node) {
  node.ontouchstart = nullEvent;
  node.ontouchend = nullEvent;
  node.ontouchcancel = nullEvent;
  node.ontouchmove = nullEvent;
}

function nullEvent(event) {
  var e = event || window.event;
  e.preventDefault && e.preventDefault();
  e.stopPropagation && e.stopPropagation();
  e.cancelBubble = true;
  e.returnValue = false;
  return false;
}