'Constructor
@param tab: the component tab configuration as tuple
(label, component_alias, {get_vars}), where the
get_vars dict is optional.'

def __init__(self, tab):

    (title, component) = tab[:2]
    if (component and (component.find('/') > 0)):
        (function, component) = component.split('/', 1)
    else:
        function = None
    self.title = title
    self.native = False
    if function:
        self.function = function
    else:
        self.function = None
    if component:
        self.component = component
    else:
        self.component = None
    if (len(tab) > 2):
        vars = self.vars = Storage(tab[2])
        if ('native' in vars):
            self.native = (True if vars['native'] else False)
            del vars['native']
    else:
        self.vars = None
