gistfile1.txt

from kivy.models import SelectableDataItem
from kivy.uix.gridlayout import GridLayout
from kivy.uix.listview import ListView
from kivy.uix.listview import ListItemButton
from kivy.uix.objectview import ObjectView

from fixtures import fruit_categories, fruit_data_list_of_dicts

class CategoryItem(SelectableDataItem):
    def __init__(self, **kwargs):
        super(CategoryItem, self).__init__(**kwargs)
        self.name = kwargs.get('name', '')
        self.fruits = kwargs.get('fruits', [])
        self.is_selected = kwargs.get('is_selected', False)


class FruitItem(SelectableDataItem):
    def __init__(self, **kwargs):
        super(FruitItem, self).__init__(**kwargs)
        self.name = kwargs.get('name', '')
        self.serving_size = kwargs.get('Serving Size', '')
        self.data = kwargs.get('data', [])
        self.is_selected = kwargs.get('is_selected', False)


# To instantiate CategoryItem and FruitItem instances, we use the dictionary-
# style fixtures data in fruit_data (See import above), which is
# also used by other list examples. The double asterisk usage here is for
# setting arguments from a dict in calls to instantiate the custom data item
# classes defined above.

# fruit_categories is a dict of dicts.
category_data_items = \
    [CategoryItem(**fruit_categories[c]) for c in sorted(fruit_categories)]

# fruit_data_list_of_dicts is a list of dicts, already sorted.
fruit_data_items = \
    [FruitItem(**fruit_dict) for fruit_dict in fruit_data_list_of_dicts]

# We end up with two normal lists of objects, to be used for two list views
# defined below.


class CascadingView(GridLayout):
    '''Implementation of a master-detail style view, with a scrollable list
    of fruit categories on the left, a list of fruits for the selected
    category in the middle, and a detail view on the right.
    '''

    def __init__(self, **kwargs):
        kwargs['cols'] = 3
        super(CascadingView, self).__init__(**kwargs)

        list_item_args_converter = \
                lambda row_index, selectable: {'text': selectable.name,
                                               'size_hint_y': None,
                                               'height': 25}

        fruit_categories_list_view = \
                ListView(data=category_data_items,
                         args_converter=list_item_args_converter,
                         selection_mode='single',
                         allow_empty_selection=False,
                         cls=ListItemButton,
                         size_hint=(.2, 1.0))

        fruits_list_view = \
                ListView(data=Binding(
                    source=fruit_categories_list_view.adapter,
                    transform=(binding_transforms.TRANSFORM,
                               lambda v: [f in fruit_data_items
                                          if f.name in category_data_items[v.index].fruits])),
                         args_converter=list_item_args_converter,
                         selection_mode='single',
                         allow_empty_selection=False,
                         cls=ListItemButton,
                         size_hint=(.2, 1.0))

        fruit_view = ObjectView(
                data=Binding(
                    source=fruit_view.adapter,
                    prop='selection',
                    mode=bindings.FIRST_ITEM,
                    transform=(binding_transforms.TRANSFORM,
                               lambda v: App.app().current_fruits_adapter.data[v.index])),
                size_hint=(.6, 1.0))

        self.add_widget(fruit_categories_list_view)
        self.add_widget(fruits_list_view)
        self.add_widget(fruit_view)


if __name__ == '__main__':

    from kivy.base import runTouchApp

    runTouchApp(CascadingView(width=800))