Global event bus


The example given in the paragraph " Subscribing to global events" of the page “” works fine.
If the “topLayout” is put in a tab of a tabbar, it still works fine.
But, if the tabbar is put in a top level layout, the global event bus seems not to work, i.e, when clicking on a button of the toolbar, nothing happens, the empty view is not refreshed.
Thanks for your help