Context menu for extjs grid

Well, depending on what you want to do you can handle the following GridPanel events in the same manner as your example: contextmenu, cellcontextmenu, containercontextmenu, groupcontextmenu, headercontextmenu, rowbodycontextmenu or rowcontextmenu.

First define your context menu

mnuContext = new Ext.menu.Menu({
    items: [{
        id: 'do-something',
        text: 'Do something'
    }],
    listeners: {
        itemclick: function(item) {
            switch (item.id) {
                case 'do-something':
                    break;
            }
        }
    }
});

Then create a listener for the desired event. It is very important to remember to stop the event's default behaviour so you can replace it with your own. If you don't call the event.stopEvent() method to stop the event bubbling onwards then the brower's default context menu will appear regardless of what you do.

rowcontextmenu: function(grid, index, event){
     event.stopEvent();
     mnuContext.showAt(event.xy);
}

from http://stackoverflow.com/questions/3280101/how-i-can-create-context-menu-for-extjs-grid