Raphael canvas (background) onclick event

Question

I have been working with Raphael to create drag and drop shapes on a canvas. I do this using the .drag() function (supplied in the Raphael framework) along with my event functions. I have no issues doing this.

I also have a function that creates a new shape onDblClick, the problem is, I can only attach the event to a shapes, or other elements I create.

Adding events to a shape works like so:

  R = Raphael("canvas", "100%", "100%"),
  R.rect(100, 100, 25, 50).attr({fill: fillColor}).dblclick(myDblClick);

Using the same principle on the canvas doesn't work:

  R = Raphael("canvas", "100%", "100%"),
  R.dblclick(myDblClick);

Does anybody know a way to attach click events to the canvas, i.e. I can click anywhere in the div (excluding shapes) and the event will be triggered.

score 19 · Answer 1 · answered Oct 17 '11 at 14:37

As the accepted answer didn't work for me (though it did get me on the right track) I thought I would post how I solved it in case there is anybody else in my position...

//Create paper element from canvas DIV
var canvas = $("#Canvas");
paper = Raphael("Canvas", canvas.width(), canvas.height());

//Register Event
$("#Canvas").click(CanvasClick);

//Event Handler
function CanvasClick(e) {
    if (e.target.nodeName == "svg")
    {
       //This will only occur if the actual canvas area is clicked, not any other drawn elements
    }
}

score 13 · Accepted Answer · answered Nov 11 '10 at 21:25

13

I would just attach the regular click event (with vanilla javascript, or whatever js framework you are using) to the the canvas node (or the parent node that contains the #canvas element).

With jquery:

//Bound to canvas
$('#canvas').bind('dblclick', myDblClick);
//Bound to parent
$('#canvas').parent().bind('dblclick', myDblClick);

Otherwise, if you are dead-set on using Raphael events, you could draw a rectangle over the entire canvas, and capture click events on that. but that seems like a lot of overhead.

answered Nov 11 '10 at 21:25

Kayla Rose

1,293
10
12

The issue with this is that the event is still called if a shape is clicked on. I only want the background to be applicable to this event. – Adam Holmes Nov 11 '10 at 22:15
4

Inside myDblClick, inspect the event.originalTarget and if it is node a "rect" etc. then fire a custom event. $('#canvas').trigger('dblclick.raphDblClick', {origEvent:event});. Something along those lines should work – Kayla Rose Nov 12 '10 at 19:45
Usually you move the `paper` around, so `paper.canvas` should also work. – tokland Nov 06 '12 at 23:26

score 3 · Answer 3 · answered Dec 18 '11 at 13:52

musefans solution with IE compatiblity. Thanks

//Create paper element from canvas DIV
var canvas = $("#Canvas");
paper = Raphael("Canvas", canvas.width(), canvas.height());

$("#canvas").click(canvasClick);

canvasClick: function(e) {
    if (e.target.nodeName == "svg" || e.target.nodeName == "DIV" )

},

Raphael canvas (background) onclick event

3 Answers3

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