How to use the remi.gui.Widget function in remi

self.set_text = self.editInput.set_text
        self.set_text(text)

    def onchange(self, emitter, new_value):
        return self.eventManager.propagate(self.EVENT_ONCHANGE, (new_value,))

    @decorate_set_on_listener("onchange", "(self,emitter,new_value)")
    def set_on_change_listener(self, callback, *userdata):
        """Register the listener for the onchange event.

        Note: the listener prototype have to be in the form on_item_changed(self, widget, value).
        """
        self.eventManager.register_listener(self.EVENT_ONCHANGE, callback, *userdata)


class TableItem(Widget, _MixinTextualWidget):
    """item widget for the TableRow."""

    @decorate_constructor_parameter_types([str])
    def __init__(self, text='', **kwargs):
        """
        Args:
            text (str):
            kwargs: See Widget.__init__()
        """
        super(TableItem, self).__init__(**kwargs)
        self.type = 'td'
        self.set_text(text)


class TableTitle(TableItem, _MixinTextualWidget):
    """title widget for the table."""

except (IndexError, ValueError):
                    return a > b

        log.debug("FileFolderNavigator - populate_folder_items")

        # krt sort that works in Raspbian
        l = sorted(os.listdir(directory))
        # l.sort(key=functools.cmp_to_key(_sort_files))

        # used to restore a valid path after a wrong edit in the path editor
        self._last_valid_path = directory
        # we remove the container avoiding graphic update adding items
        # this speeds up the navigation
        self.remove_child(self.itemContainer)
        # creation of a new instance of a itemContainer
        self.itemContainer = Widget(width='100%', height=300)
        self.itemContainer.set_layout_orientation(Widget.LAYOUT_VERTICAL)
        self.itemContainer.style['overflow-y'] = 'scroll'
        self.itemContainer.style['overflow-x'] = 'hidden'
        self.itemContainer.style['display'] = 'block'


        for i in l:
            full_path = os.path.join(directory, i)
            is_folder = not os.path.isfile(full_path)
            if (not is_folder) and (not self.allow_file_selection):
                continue
            fi = FileFolderItem(i, is_folder)
            fi.style['display'] = 'block'
            fi.set_on_click_listener(self.on_folder_item_click)  # navigation purpose
            fi.set_on_selection_listener(self.on_folder_item_selected)  # selection purpose
            self.folderItems.append(fi)

def main(self):
        verticalContainer = gui.Widget(width=540)
        verticalContainer.style['display'] = 'block'
        verticalContainer.style['overflow'] = 'hidden'

        horizontalContainer = gui.Widget(width='100%', layout_orientation=gui.Widget.LAYOUT_HORIZONTAL, margin='0px')
        horizontalContainer.style['display'] = 'block'
        horizontalContainer.style['overflow'] = 'auto'
        
        subContainerLeft = gui.Widget(width=320)
        subContainerLeft.style['display'] = 'block'
        subContainerLeft.style['overflow'] = 'auto'
        subContainerLeft.style['text-align'] = 'center'
        self.img = gui.Image('/res/logo.png', width=100, height=100, margin='10px')
        self.img.set_on_click_listener(self, 'on_img_clicked')

        self.table = gui.Table(width=300, height=200, margin='10px')
        self.table.from_2d_matrix([['ID', 'First Name', 'Last Name'],

    @decorate_set_on_listener("(self, emitter, fileList)")
    @decorate_event
    def confirm_value(self, widget):
        """event called pressing on OK button.
           propagates the string content of the input field
        """
        self.hide()
        params = (self.fileFolderNavigator.get_selection_list(),)
        return params

    @decorate_explicit_alias_for_listener_registration
    def set_on_confirm_value_listener(self, callback, *userdata):
        self.confirm_value.connect(callback, *userdata)


class MenuBar(Widget):

    @decorate_constructor_parameter_types([])
    def __init__(self, *args, **kwargs):
        """
        Args:
            kwargs: See Widget.__init__()
        """
        super(MenuBar, self).__init__(*args, **kwargs)
        self.type = 'nav'
        self.set_layout_orientation(Container.LAYOUT_HORIZONTAL)


class Menu(Widget):
    """Menu widget can contain MenuItem."""

    @decorate_constructor_parameter_types([])

Args:
            callback (function): Callback function pointer.
        """
        self.attributes[self.EVENT_ONKEYDOWN] = """
            if (event.keyCode == 13) {
                var params={};
                params['new_value']=document.getElementById('%(id)s').value;
                document.getElementById('%(id)s').value = '';
                document.getElementById('%(id)s').onchange = '';
                sendCallbackParam('%(id)s','%(evt)s',params);
                return false;
            }""" % {'id': self.identifier, 'evt': self.EVENT_ONENTER}
        self.eventManager.register_listener(self.EVENT_ONENTER, callback, *userdata)


class Label(Widget, _MixinTextualWidget):
    """Non editable text label widget. Set its content by means of set_text function, and retrieve its content with the
    function get_text.
    """
    @decorate_constructor_parameter_types([str])
    def __init__(self, text, **kwargs):
        """
        Args:
            text (str): The string content that have to be displayed in the Label.
            kwargs: See Widget.__init__()
        """
        super(Label, self).__init__(**kwargs)
        self.type = 'p'
        self.set_text(text)


class GenericDialog(Widget):

subContainerLeft = gui.Widget(width=320,
                                      style={'display': 'block', 'overflow': 'auto', 'text-align': 'center'})
        self.img = gui.Image('/res:logo.png', height=100, margin='10px')
        self.img.onclick.connect(self.on_img_clicked)

        self.table = gui.Table.new_from_list([('ID', 'First Name', 'Last Name'),
                                              ('101', 'Danny', 'Young'),
                                              ('102', 'Christine', 'Holand'),
                                              ('103', 'Lars', 'Gordon'),
                                              ('104', 'Roberto', 'Robitaille'),
                                              ('105', 'Maria', 'Papadopoulos')],
                                             width=300, height=200, margin='10px')
        self.table.on_table_row_click.connect(self.on_table_row_click)

        # the arguments are width - height - layoutOrientationOrizontal
        subContainerRight = gui.Widget(
            style={'width': '220px', 'display': 'block',
                   'overflow': 'auto', 'text-align': 'center'})
        self.count = 0
        self.counter = gui.Label('', width=200, height=30, margin='10px')

        self.lbl = gui.Label('This is a LABEL!', width=200,
                             height=30, margin='10px')

        self.bt = gui.Button('Press me!', width=200, height=30, margin='10px')
        # setting the listener for the onclick event of the button
        self.bt.onclick.connect(self.on_button_pressed)

        self.txt = gui.TextInput(width=200, height=30, margin='10px')
        self.txt.set_text('This is a TEXTAREA')
        self.txt.onchange.connect(self.on_text_area_change)

GenericObject widget - allows to show embedded object like pdf,swf..
    """

    @decorate_constructor_parameter_types([str])
    def __init__(self, filename, **kwargs):
        """
        Args:
            filename (str): URL
            kwargs: See Widget.__init__()
        """
        super(GenericObject, self).__init__(**kwargs)
        self.type = 'object'
        self.attributes['data'] = filename


class FileFolderNavigator(Widget):
    """FileFolderNavigator widget."""

    @decorate_constructor_parameter_types([bool, str, bool, bool])
    def __init__(self, multiple_selection, selection_folder, allow_file_selection, allow_folder_selection, **kwargs):
        super(FileFolderNavigator, self).__init__(**kwargs)
        self.set_layout_orientation(Widget.LAYOUT_VERTICAL)
        self.style['width'] = '100%'

        self.multiple_selection = multiple_selection
        self.allow_file_selection = allow_file_selection
        self.allow_folder_selection = allow_folder_selection
        self.selectionlist = []
        self.controlsContainer = Widget()
        self.controlsContainer.set_size('100%', '30px')
        self.controlsContainer.style['display'] = 'flex'
        self.controlsContainer.set_layout_orientation(Widget.LAYOUT_HORIZONTAL)

self.text +=text+'\n'
        self.textb.set_value(self.text)  

#  ****************************************************
# TabView - a framework for a Tabbed Editor
#  ****************************************************

"""
The TabView constucts a container.
The container has a tab bar, tab title and a frame (self.tab_frame).
The tab_frame can contain one of many panels depending on the tab selected
add_tab adds a button to the tab bar, and creates and returns a panel 

"""

class TabView(gui.Widget):
    def __init__(self, frame_width,frame_height,bar_height,**kwargs):
        super(TabView, self).__init__(**kwargs)
        
        self.bar_width=0
        self.bar_height=bar_height
        self.frame_width=frame_width
        self.frame_height=frame_height
        
        self.set_layout_orientation(gui.Widget.LAYOUT_VERTICAL)

        
        #dictionary to  lookup panel object given key
        self.panel_obj=dict()
        self.tab_titles=dict()
        
        #tab bar

kwargs: See Widget.__init__()
        """
        super(MenuItem, self).__init__(**kwargs)
        self.sub_container = None
        self.type = 'li'
        self.attributes[self.EVENT_ONCLICK] = ''
        self.set_text(text)

    def append(self, value, key=''):
        if self.sub_container is None:
            self.sub_container = Menu()
            super(MenuItem, self).append(self.sub_container, key='subcontainer')
        self.sub_container.append(value, key=key)


class TreeView(Widget):
    """TreeView widget can contain TreeItem."""

    @decorate_constructor_parameter_types([])
    def __init__(self, **kwargs):
        """
        Args:
            kwargs: See Widget.__init__()
        """
        super(TreeView, self).__init__(**kwargs)
        self.type = 'ul'


class TreeItem(Widget, _MixinTextualWidget):
    """TreeItem widget can contain other TreeItem."""

    @decorate_constructor_parameter_types([str])

text (str, unicode): The textual content of the ListItem.
            kwargs: See Widget.__init__()
        """
        super(ListItem, self).__init__(*args, **kwargs)
        self.type = 'li'
        self.set_text(text)

    def get_value(self):
        """
        Returns:
            str: The text content of the ListItem
        """
        return self.get_text()


class DropDown(Widget):
    """Drop down selection widget. Implements the onchange(value) event. Register a listener for its selection change
    by means of the function DropDown.onchange.connect.
    """

    @decorate_constructor_parameter_types([])
    def __init__(self, *args, **kwargs):
        """
        Args:
            kwargs: See Widget.__init__()
        """
        super(DropDown, self).__init__(*args, **kwargs)
        self.type = 'select'
        self.attributes[self.EVENT_ONCHANGE] = \
            "var params={};params['value']=document.getElementById('%(id)s').value;" \
            "sendCallbackParam('%(id)s','%(evt)s',params);" % {'id': self.identifier,
                                                               'evt': self.EVENT_ONCHANGE}