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jquery - Html5 drag and drop on svg element

I am trying to follow the html5 drag and drop tutorial here. I could not get the dragstart event to be registered on rect element. If I change the event from draggable to mousedown it calls the handleDragStart handler. Please ignore the additional blank registration in the code.

JSFiddle here


<!DOCTYPE html>
<html><head>
  <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
  <style type="text/css" media="screen">
    svg rect { cursor: move; }
  </style>
</head><body>
  <h1>SVG/HTML 5 Example</h1>
  <svg id="cvs">
    <rect draggable="true" x="0" y="10" width="100" height="80" fill="#69c" />
    <rect x="50" y="50" width="90" height="50" fill="#c66" />        
  </svg>
  <script type="text/javascript" src="loc.js"></script>
</body></html>

loc.js

$(document).ready(function() {    
    function handleDragStart(e) {
        log("handleDragStart");                
          this.style.opacity = '0.4';  // this ==> e.target is the source node.
    };

    var registercb = function () {
            $("#cvs > rect").each(function() {
                  $(this).attr('draggable', 'true');
              });
            $("#cvs > rect").bind('dragstart', handleDragStart);    
            $(window).mousedown(function (e) {        

            });    
            $(window).mousemove(function (e) {                
            });
            $(window).mouseup(function (e) {
                log("mouseup");                
            });
        };

    function log() {
      if (window.console && window.console.log)
        window.console.log('[XXX] ' + Array.prototype.join.call(arguments, ' '));
    };

    registercb();
}); 
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1 Answer

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I know this is an old question, I arrived here from this other question that was marked as a duplicate of this one, and wanted to add a possible solution that doesn't require jQuery or any libraries, and that works in all major browsers. It is based on this tutorial recommended by @AmirHossein Mehrvarzi.

This small solution doesn't use the drag events, just the mousedown, mouseup and mousemove. This is how it works:

  • When the mouse is down on the rectangle, it saves the mouse position and the active element.
  • When the mouse moves, the rectangle coordinates are updated with the new mouse position.
  • When the mouse is up, it resets the active element.

From the code in the question above:

var selectedElement = null;
var currentX = 0;
var currentY = 0;

$(document).ready(function() {
    
    function handleDragStart(e) {
        log("handleDragStart");                
        this.style.opacity = '0.4';  // this ==> e.target is the source node.
    };
    
    var registercb = function () {
       
        $("#cvs > rect").mousedown(function (e) {
            // save the original values when the user clicks on the element
            currentX = e.clientX;
            currentY = e.clientY;
            selectedElement = e.target;
        }).mousemove(function (e) {    
            // if there is an active element, move it around by updating its coordinates           
            if (selectedElement) {
                var dx = parseInt(selectedElement.getAttribute("x")) + e.clientX - currentX;
                var dy = parseInt(selectedElement.getAttribute("y")) + e.clientY - currentY;
                currentX = e.clientX;
                currentY = e.clientY;
                selectedElement.setAttribute("x", dx);
                selectedElement.setAttribute("y", dy);
            }
        }).mouseup(function (e) {
            // deactivate element when the mouse is up
            selectedElement = null;  
        });
    };
    
    function log() {
        if (window.console && window.console.log)
            window.console.log('[XXX] ' + Array.prototype.join.call(arguments, ' '));
    };
    
    registercb();
}); 
rect { cursor: move; }
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<h1>SVG/HTML 5 Example</h1>
<svg id="cvs">
    <rect x="0" y="10" width="100" height="80" fill="#69c" />
    <rect x="50" y="50" width="90" height="50" fill="#c66" />        
</svg>

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