Component for selecting multiple items in Ext

Ext already provides a component to select multiple items. The thing I do not like about it is that it covers too much space on the screen.
Therefore I thought of a component that initially looks like a combo box and then opens a new window to let the user select the items.

As a nice example tells more than thousand words – here it is:

As you can see, it is actually based on the component provided by the Ext examples.

And here’s the source code for the example:

Altough the example binds an in-memory store, you can also use an external store. If so, please remove the mode property – similar to a combo box.

Update: You can find this code and all my other ExtJS components bundled in a library called ‘extensive’. Enjoy the code and feel free to support the project by participating.