How to use the khal.ui.widgets.ExtendedEdit function in khal

def __init__(self, parent):
        self.parent = parent
        self._edit = ExtendedEdit('', parent.active)
        urwid.connect_signal(self._edit, 'change',
                             lambda edit, text: self.filter(text))
        self._walker = urwid.SimpleFocusListWalker([self._edit])
        walker = urwid.BoxAdapter(
            urwid.ListBox(self._walker), height=self.parent.win_len - 1)
        self._pile = NPile([self._edit, walker], outermost=True)
        self.filter('')
        self.focus_on(self.parent.active)
        fill = urwid.Filler(self._pile, 'top')
        urwid.WidgetWrap.__init__(self, urwid.AttrMap(fill, 'popupbg'))

def _delete_till_end_of_line(self):
        """delete till end of line before cursor"""
        text = self.get_edit_text()
        f_text = delete_till_end_of_line(text[self.edit_pos:])
        self.set_edit_text(text[:self.edit_pos] + f_text)

    def _goto_beginning_of_line(self):
        text = self.get_edit_text()
        self.set_edit_pos(goto_beginning_of_line(text[:self.edit_pos]))

    def _goto_end_of_line(self):
        text = self.get_edit_text()
        self.set_edit_pos(goto_end_of_line(text[self.edit_pos:]) + self.edit_pos)


class EnterEdit(ExtendedEdit):
    """Edit class that emits signal `enter` if user tries to edit"""
    signals = ['enter']

    def keypress(self, size, key):
        if key not in ['up', 'down', 'left', 'right', 'tab', 'shift tab']:
            self._emit('enter')
            return
        else:
            return super().keypress(size, key)


class DateTimeWidget(ExtendedEdit):

    def __init__(self, dateformat, on_date_change=lambda x: None, **kwargs):
        self.dateformat = dateformat
        self.on_date_change = on_date_change

def __init__(self, this_func, abort_func, event):
        lines = []
        lines.append(urwid.Text('Export event as ICS file'))
        lines.append(urwid.Text(''))
        export_location = ExtendedEdit(
            caption='Location: ', edit_text="~/%s.ics" % event.summary.strip())
        lines.append(export_location)
        lines.append(urwid.Divider(' '))
        lines.append(
            urwid.Button('Save', on_press=this_func, user_data=export_location)
        )
        content = NPile(lines)
        urwid.WidgetWrap.__init__(self, urwid.LineBox(content))

def __init__(self, alarm, delete_handler):
            duration, description = alarm
            if duration.total_seconds() > 0:
                direction = 'after'
            else:
                direction = 'before'
                duration = -1 * duration

            self.duration = DurationWidget(duration)
            self.description = ExtendedEdit(edit_text=description)
            self.direction = Choice(
                ['before', 'after'], active=direction, overlay_width=10)
            self.columns = NColumns([
                (2, urwid.Text('  ')),
                (21, self.duration),
                (14, urwid.Padding(self.direction, right=1)),
                self.description,
                (10, urwid.Button('Delete', on_press=delete_handler, user_data=self)),
            ])

            urwid.WidgetWrap.__init__(self, self.columns)

self.set_edit_pos(goto_end_of_line(text[self.edit_pos:]) + self.edit_pos)


class EnterEdit(ExtendedEdit):
    """Edit class that emits signal `enter` if user tries to edit"""
    signals = ['enter']

    def keypress(self, size, key):
        if key not in ['up', 'down', 'left', 'right', 'tab', 'shift tab']:
            self._emit('enter')
            return
        else:
            return super().keypress(size, key)


class DateTimeWidget(ExtendedEdit):

    def __init__(self, dateformat, on_date_change=lambda x: None, **kwargs):
        self.dateformat = dateformat
        self.on_date_change = on_date_change
        super().__init__(wrap='any', **kwargs)

    def keypress(self, size, key):
        if key == 'ctrl x':
            self.decrease()
            return None
        elif key == 'ctrl a':
            self.increase()
            return None

        if (
                key in ['up', 'down', 'tab', 'shift tab'] or

self._abort_confirmed = False

        self.description = event.description
        self.location = event.location
        self.categories = event.categories
        self.startendeditor = StartEndEditor(
            event.start_local, event.end_local, self._conf,
            self.start_datechange, self.end_datechange,
        )
        # TODO make sure recurrence rules cannot be edited if we only
        # edit one instance (or this and future) (once we support that)
        self.recurrenceeditor = RecurrenceEditor(
            self.event.recurobject, self._conf, event.start_local,
        )
        self.summary = urwid.AttrMap(ExtendedEdit(
            caption=('', 'Title:       '), edit_text=event.summary), 'edit'
        )

        divider = urwid.Divider(' ')

        def decorate_choice(c):
            return ('calendar ' + c['name'], c['name'])

        self.calendar_chooser = Choice(
            [self.collection._calendars[c] for c in self.collection.writable_names],
            self.collection._calendars[self.event.calendar],
            decorate_choice
        )
        self.description = urwid.AttrMap(
            ExtendedEdit(
                caption=('', 'Description: '),

self.summary = urwid.AttrMap(ExtendedEdit(
            caption=('', 'Title:       '), edit_text=event.summary), 'edit'
        )

        divider = urwid.Divider(' ')

        def decorate_choice(c):
            return ('calendar ' + c['name'], c['name'])

        self.calendar_chooser = Choice(
            [self.collection._calendars[c] for c in self.collection.writable_names],
            self.collection._calendars[self.event.calendar],
            decorate_choice
        )
        self.description = urwid.AttrMap(
            ExtendedEdit(
                caption=('', 'Description: '),
                edit_text=self.description,
                multiline=True
            ),
            'edit'
        )
        self.location = urwid.AttrMap(ExtendedEdit(
            caption=('', 'Location:    '), edit_text=self.location), 'edit'
        )
        self.categories = urwid.AttrMap(ExtendedEdit(
            caption=('', 'Categories:  '), edit_text=self.categories), 'edit'
        )
        self.alarms = AlarmsEditor(self.event)
        self.pile = NListBox(urwid.SimpleFocusListWalker([
            self.summary,
            urwid.Columns([(12, self.calendar_chooser)]),

def keypress(self, size, key):
        if key == 'ctrl w':
            self._delete_word()
        elif key == 'ctrl u':
            self._delete_till_beginning_of_line()
        elif key == 'ctrl k':
            self._delete_till_end_of_line()
        elif key == 'ctrl a':
            self._goto_beginning_of_line()
        elif key == 'ctrl e':
            self._goto_end_of_line()
        else:
            return super(ExtendedEdit, self).keypress(size, key)

def __init__(self, search_func, abort_func):

        class Search(Edit):

            def keypress(self, size, key):
                if key == 'enter':
                    search_func(self.text)
                else:
                    return super().keypress(size, key)

        search_field = Search('')

        def this_func(_):
            search_func(search_field.text)

        lines = []
        lines.append(urwid.Text('Please enter a search term (Escape cancels):'))
        lines.append(search_field)
        buttons = NColumns([urwid.Button('Search', on_press=this_func),

def __init__(self, search_func, abort_func):

        class Search(Edit):

            def keypress(self, size, key):
                if key == 'enter':
                    search_func(self.text)
                else:
                    return super().keypress(size, key)

        search_field = Search('')

        def this_func(_):
            search_func(search_field.text)

        lines = []
        lines.append(urwid.Text('Please enter a search term (Escape cancels):'))
        lines.append(search_field)
        buttons = NColumns([urwid.Button('Search', on_press=this_func),