You're going to need to study the code to figure it out. I forget how it's done with the different code bases.
You need to be able to figure that much out because implementing the rest of the code will be more difficult than that.
On a tangent note, I redid the bottom taskbar to use border layouts and plopped instances of Toolbar in those regions. Then it makes it easy to use the standard Ext API to add/remove items from those containers.
i study http://www.qwikioffice.com/desktop-demo code but regrading to that i need to
change lot of it to made it work.
it is little complicated because my desktop features that i develop on ext desktop demo will not work
If anyone know simple solution to add icon on quick start it will be much appreciated