from kivy.uix.gridlayout import GridLayout from kivy.uix.label import Label from kivy.uix.button import Button from kivy.uix.listview import ListView, ListAdapter from kivy.uix.mixins.selection import SelectionObserver, SelectableItem from kivy.properties import ListProperty, StringProperty, ObjectProperty from kivy.clock import Clock from kivy.graphics.instructions import Callback # This is an expansion on the "master-detail" example to illustrate # cascading from the selection of one list view to another. # Generic list item will do fine for both list views: class ListItem(SelectableItem, Button): selected_color = ListProperty([1., 0., 0., 1]) deselected_color = None def __init__(self, list_adapter, **kwargs): self.list_adapter = list_adapter super(ListItem, self).__init__(**kwargs) # Set deselected_color to be default Button bg color. self.deselected_color = self.background_color self.bind(on_release=self.handle_selection) def handle_selection(self, button): self.list_adapter.handle_selection(self) def select(self, *args): print self.text, 'is now selected' self.background_color = self.selected_color def deselect(self, *args): print self.text, 'is now unselected' self.background_color = self.deselected_color def __repr__(self): return self.text class FruitsListView(SelectionObserver, ListView): # The fruit categories list view can be a simple ListView, # but the fruits list, showing fruits for a given category, # will be a SelectionObserver, changing when fruit category # changes. def __init__(self, **kwargs): super(FruitsListView, self).__init__(**kwargs) # Observed selection is fruit categories list. def observed_selection_changed(self, list_adapter, selection): if len(list_adapter.selection) == 0: return # Clear the previously built views. self.item_view_instances = {} # Single selection is operational for fruit categories list. selected_object = list_adapter.selection[0] if type(selected_object) is str: fruit_category = selected_object else: fruit_category = str(selected_object) # Reset data for the adapter. This will trigger a call # to self.adapter.initialize_selection(). self.adapter.data = fruit_categories[fruit_category] #print self.adapter.selection[0], self.adapter.selection[0].background_color self.populate() #self.canvas.ask_update() print 'just added or updated fruit category' class DetailView(SelectionObserver, GridLayout): fruit_name = StringProperty('') def __init__(self, **kwargs): kwargs['cols'] = 2 super(DetailView, self).__init__(**kwargs) self.bind(fruit_name=self.redraw) def redraw(self, *args): self.clear_widgets() self.add_widget(Label(text="Name:", halign='right')) self.add_widget(Label(text=self.fruit_name)) for category in descriptors: self.add_widget(Label(text="{0}:".format(category), halign='right')) self.add_widget( Label(text=str(fruit_data[self.fruit_name][category]))) def observed_selection_changed(self, list_adapter, selection): if len(list_adapter.selection) == 0: return selected_object = list_adapter.selection[0] # Resetting self.fruit_name will trigger call to redraw(). # [TODO] Why not direct call to redraw here? (And remove binding). if type(selected_object) is str: self.fruit_name = selected_object else: self.fruit_name = str(selected_object) print 'just added or updated detail label' class CascadingView(GridLayout): '''Implementation of a master-detail style view, with a scrollable list of fruit categories on the left (source list), a list of fruits for the selected category in the middle, and a detail view on the right. ''' fruit_categories_list_adapter = ObjectProperty(None) fruit_categories_list_view = ObjectProperty(None) fruits_list_adapter = ObjectProperty(None) fruits_list_view = ObjectProperty(None) detail_view = ObjectProperty(None) def __init__(self, fruit_categories, fruits, **kwargs): kwargs['cols'] = 3 kwargs['size_hint'] = (1.0, 1.0) super(CascadingView, self).__init__(**kwargs) list_item_args_converter = lambda x: {'text': x, 'size_hint_y': None, 'height': 25} # Fruit categories list on the left: # self.fruit_categories_list_adapter = \ ListAdapter(fruit_categories, args_converter=list_item_args_converter, selection_mode='single', allow_empty_selection=False, cls=ListItem) self.fruit_categories_list_view = \ ListView(adapter=self.fruit_categories_list_adapter, size_hint=(.2, 1.0)) self.add_widget(self.fruit_categories_list_view) # Fruits, for a given category, in the middle: # self.fruits_list_adapter = \ ListAdapter(fruits, args_converter=list_item_args_converter, selection_mode='single', allow_empty_selection=False, cls=ListItem) self.fruits_list_view = \ FruitsListView(adapter=self.fruits_list_adapter, size_hint=(.2, 1.0)) self.add_widget(self.fruits_list_view) # Set the fruits_list_view as an observer of the selection of # the fruit categories list. self.fruit_categories_list_adapter.bind( selection=self.fruits_list_view.observed_selection_changed) # Detail view, for a given fruit, on the right: # self.detail_view = DetailView(size_hint=(.6, 1.0)) self.add_widget(self.detail_view) self.fruits_list_adapter.bind( selection=self.detail_view.observed_selection_changed) # Manually re-initialize selection of fruit category to fire updates # to observing views in the chain: # # fruit categories list -> fruits list -> detail view # # These lists are set up for auto-selection, but the dispatching # that happens on instantiation would have already fired. # self.fruit_categories_list_adapter.initialize_selection() # [TODO] Why is this call also needed? self.fruits_list_adapter.initialize_selection() # Data from http://www.fda.gov/Food/LabelingNutrition/\ # FoodLabelingGuidanceRegulatoryInformation/\ # InformationforRestaurantsRetailEstablishments/\ # ucm063482.htm fruit_categories = \ {'Melons': ['Cantaloupe', 'Honeydew Melon', 'Watermelon'], 'Tree Fruits': ['Apple', 'Avocado, California', 'Banana', 'Nectarine', 'Peach', 'Pear', 'Pineapple', 'Plums', 'Sweet Cherries'], 'Citrus Fruits': ['Grapefruit', 'Lemon', 'Lime', 'Orange', 'Tangerine'], 'Miscellaneous Fruits': ['Grapes', 'Kiwifruit', 'Strawberries']} descriptors = """(gram weight/ ounce weight) Calories Calories from Fa t Total Fat Sodium Potassium Total Carbo-hydrate Dietary Fiber Suga rs Protein Vitamin A Vitamin C Calcium Iron""".replace('\n', '') descriptors = [item.strip() for item in descriptors.split('\t')] units = """(g) (%DV) (mg) (%DV) (mg) (%DV) (g) (%DV) (g) (%DV) (g) (g) (%DV) (%DV) (%DV) (%DV)""".replace('\n', '') units = [item.strip() for item in units.split('\t')] raw_fruit_data = [ {'name':'Apple', 'Serving Size': '1 large (242 g/8 oz)', 'data': [130, 0, 0, 0, 0, 0, 260, 7, 34, 11, 5, 20, 25, 1, 2, 8, 2, 2]}, {'name':'Avocado, California', 'Serving Size': '1/5 medium (30 g/1.1 oz)', 'data': [50, 35, 4.5, 7, 0, 0, 140, 4, 3, 1, 1, 4, 0, 1, 0, 4, 0, 2]}, {'name':'Banana', 'Serving Size': '1 medium (126 g/4.5 oz)', 'data': [110, 0, 0, 0, 0, 0, 450, 13, 30, 10, 3, 12, 19, 1, 2, 15, 0, 2]}, {'name':'Cantaloupe', 'Serving Size': '1/4 medium (134 g/4.8 oz)', 'data': [50, 0, 0, 0, 20, 1, 240, 7, 12, 4, 1, 4, 11, 1, 120, 80, 2, 2]}, {'name':'Grapefruit', 'Serving Size': '1/2 medium (154 g/5.5 oz)', 'data': [60, 0, 0, 0, 0, 0, 160, 5, 15, 5, 2, 8, 11, 1, 35, 100, 4, 0]}, {'name':'Grapes', 'Serving Size': '3/4 cup (126 g/4.5 oz)', 'data': [90, 0, 0, 0, 15, 1, 240, 7, 23, 8, 1, 4, 20, 0, 0, 2, 2, 0]}, {'name':'Honeydew Melon', 'Serving Size': '1/10 medium melon (134 g/4.8 oz)', 'data': [50, 0, 0, 0, 30, 1, 210, 6, 12, 4, 1, 4, 11, 1, 2, 45, 2, 2]}, {'name':'Kiwifruit', 'Serving Size': '2 medium (148 g/5.3 oz)', 'data': [90, 10, 1, 2, 0, 0, 450, 13, 20, 7, 4, 16, 13, 1, 2, 240, 4, 2]}, {'name':'Lemon', 'Serving Size': '1 medium (58 g/2.1 oz)', 'data': [15, 0, 0, 0, 0, 0, 75, 2, 5, 2, 2, 8, 2, 0, 0, 40, 2, 0]}, {'name':'Lime', 'Serving Size': '1 medium (67 g/2.4 oz)', 'data': [20, 0, 0, 0, 0, 0, 75, 2, 7, 2, 2, 8, 0, 0, 0, 35, 0, 0]}, {'name':'Nectarine', 'Serving Size': '1 medium (140 g/5.0 oz)', 'data': [60, 5, 0.5, 1, 0, 0, 250, 7, 15, 5, 2, 8, 11, 1, 8, 15, 0, 2]}, {'name':'Orange', 'Serving Size': '1 medium (154 g/5.5 oz)', 'data': [80, 0, 0, 0, 0, 0, 250, 7, 19, 6, 3, 12, 14, 1, 2, 130, 6, 0]}, {'name':'Peach', 'Serving Size': '1 medium (147 g/5.3 oz)', 'data': [60, 0, 0.5, 1, 0, 0, 230, 7, 15, 5, 2, 8, 13, 1, 6, 15, 0, 2]}, {'name':'Pear', 'Serving Size': '1 medium (166 g/5.9 oz)', 'data': [100, 0, 0, 0, 0, 0, 190, 5, 26, 9, 6, 24, 16, 1, 0, 10, 2, 0]}, {'name':'Pineapple', 'Serving Size': '2 slices, 3" diameter, 3/4" thick (112 g/4 oz)', 'data': [50, 0, 0, 0, 10, 0, 120, 3, 13, 4, 1, 4, 10, 1, 2, 50, 2, 2]}, {'name':'Plums', 'Serving Size': '2 medium (151 g/5.4 oz)', 'data': [70, 0, 0, 0, 0, 0, 230, 7, 19, 6, 2, 8, 16, 1, 8, 10, 0, 2]}, {'name':'Strawberries', 'Serving Size': '8 medium (147 g/5.3 oz)', 'data': [50, 0, 0, 0, 0, 0, 170, 5, 11, 4, 2, 8, 8, 1, 0, 160, 2, 2]}, {'name':'Sweet Cherries', 'Serving Size': '21 cherries; 1 cup (140 g/5.0 oz)', 'data': [100, 0, 0, 0, 0, 0, 350, 10, 26, 9, 1, 4, 16, 1, 2, 15, 2, 2]}, {'name':'Tangerine', 'Serving Size': '1 medium (109 g/3.9 oz)', 'data': [50, 0, 0, 0, 0, 0, 160, 5, 13, 4, 2, 8, 9, 1, 6, 45, 4, 0]}, {'name':'Watermelon', 'Serving Size': '1/18 medium melon; 2 cups diced pieces (280 g/10.0 oz)', 'data': [80, 0, 0, 0, 0, 0, 270, 8, 21, 7, 1, 4, 20, 1, 30, 25, 2, 4]}] fruit_data = {} descriptors_and_units = dict(zip(descriptors, units)) for row in raw_fruit_data: fruit_data[row['name']] = {} fruit_data[row['name']] = dict({'Serving Size': row['Serving Size']}, **dict(zip(descriptors_and_units.keys(), row['data']))) if __name__ == '__main__': from kivy.base import runTouchApp # All fruit categories will be shown in the left left (first argument), # and the first category will be auto-selected -- Melons. So, set the # second list to show the melon fruits (second argument). fruit_categories_detail = CascadingView(fruit_categories.keys(), fruit_categories['Melons'], width=800) runTouchApp(fruit_categories_detail)