Custom cursor with drag and drop an HTML element without libraries

Travenin picture Travenin · Jun 9, 2017 · Viewed 10.5k times · Source

I have an HTML page which has some draggable elements. Our specs say that hovering mouse on such element the cursor must be grab grab, and during drag cursor must be grabbing grabbing.

I know it is possible to set dropEffect which changes cursor appearance above drop zone, but there are very little options: copy, move, link, and none -- no custom or alike.

I have tried to change cursor with Javascript and CSS, like setting cursor: grabbing; when ondragstart is fired. But browser default move cursor appears instead when dragging on drop zone.

So the question is: What am I missing to show grabbing cursor (grabbing) during drag?

Unfortunately I cannot use JQuery or other helping libraries in the solution. Thanks in advance!

Answer

Javier Rey picture Javier Rey · Jun 18, 2017

It seems that browsers don't allow changing the cursor at the beginning of a drag & drop operation. I don't know why but it's a known issue, I believe they will in the future.

If jQuery is not an option, a possible way around is to implement a drag & drop from scratch, using mouse events and cloning the source element:

var onDragStart = function (event) {
  event.preventDefault();
  var clone = event.target.cloneNode(true);
  clone.classList.add("dragging");
  event.target.parentNode.appendChild(clone);
  var style = getComputedStyle(clone);
  clone.drag = {
    x: (event.pageX||(event.clientX+document.body.scrollLeft)) - clone.offsetLeft + parseInt(style.marginLeft),
    y: (event.pageY||(event.clientY+document.body.scrollTop)) - clone.offsetTop + parseInt(style.marginTop),
    source: event.target
  };
};

var onDragMove = function (event) {
  if (!event.target.drag) {return;}
  event.target.style.left = ((event.pageX||(event.clientX+document.body.scrollLeft)) - event.target.drag.x) + "px";
  event.target.style.top = ((event.pageY||(event.clientY+document.body.scrollTop)) - event.target.drag.y) + "px";
};

var onDragEnd = function (event) {
  if (!event.target.drag) {return;}
  // Define persist true to let the source persist and drop the target, otherwise persist the target.
  var persist = true;
  if (persist || event.out) {
    event.target.parentNode.removeChild(event.target);
  } else {
    event.target.parentNode.removeChild(event.target.drag.source);
  }
  event.target.classList.remove("dragging");
  event.target.drag = null;
};

var onDragOver = function (event) {
  event.preventDefault();
};
.dropzone {
  width: 500px;
  height: 200px;
  background-color: silver;
}

.block {
  position: absolute;
  background-color: pink;
  margin: 10px;
  border: 20px solid pink;
}

.draggable {
  position: absolute;
  cursor: pointer; /* IE */
  cursor: -webkit-grab;
  cursor: grab;
}

.dragging {
  cursor: -webkit-grabbing;
  cursor: grabbing;
  background-color: red;
}
<div class="dropzone" onmouseover="onDragOver(event);">
  Grab and drag block around
  <div class    = "draggable block"
    onmousedown = "onDragStart(event);"
    onmousemove = "onDragMove(event);"
    onmouseup   = "onDragEnd(event);"
    onmouseout  = "event.out = true; onDragEnd(event);"
  >
    I'm draggable
  </div>
</div>