selection and context menu

what happens when i try to use context menu and selection?

by Litote0707

HTML

<link rel="stylesheet" href="http://dev.sencha.com/deploy/ext-4.0.2a/resources/css/ext-all.css">
just some text

JavaScript

Ext.onReady(function() {
    var selection = undefined;
    
    // Context Menu
    var menu = Ext.create('Ext.menu.Menu', {
        items: [{
            text: 'Copy'
        }],
        listeners: {
            click: function(theMenu, theMenuItem){
                alert("On Context menu item:" + theMenu.theSelectedText.toString());
            }
        }
    });
    
    // Bind to contextmenu event listener 
    Ext.getDoc().on('contextmenu', function(ev) {
        selection = window.getSelection();
        menu.theSelectedText = window.getSelection().toString();
        menu.showAt(ev.getXY());
        ev.stopEvent();
    });
});