Communicate between Controllers

Hi,

here ist what I want to do:



I have a TreeController which fires an event such as:

this.fireEvent('onItemTreeSelected', {

storeId: record.data.storeId,

colDefReference: record.data.colDefinition,

selectedForm: record.data.detailForm

}

);



I have a ViewController which shall listen to that event. If I use the Actions Config I don't know how to access the TreeController and its fired Event.



Help very welcome.