Drag a draw component

[rando]

I'm trying to give drag and drop capabilities to a draw component created with touch-charts.js. I have a simple code that draws a red rectangle but I fail to call Ext.util.Draggable which returns an error:

• "Uncaught TypeError: Cannot call method 'addCls' of null"

Is this possible with touch-charts.js?

...
    onReady: function() {
       
        // Create a draw component
        var drawComponent = new Ext.draw.Component({
            height: 400,
            width: 400,
            viewBox: false
        });


        // Create a window to place the draw component in
        this.rootpanel = new Ext.Panel({
            fullscreen:true,
            layout: 'fit',
            items: [drawComponent]
        });
 
        var redRectangle = drawComponent.surface.add({
            type: 'path',
            path: 'M 50 50 h 300 v 300 h -300 Z',
            fill: '#F44'
        });

       redRectangle.animate({
            duration: 1
        });

        new Ext.util.Draggable(redRectangle, {
            revert: true
        });