Returns the index of the tab which has a particular window associated with it. Note that if you use shared window objects, only the first tab to use a particular window will be returned. Returns -1 if the supplied window object id doesn't match any attached to tabs.
Sets the text for a particular tab. By default the text is the title of the window nested in the tab, but it can be changed with this method. Returns an error if the supplied tab index is invalid.