Updated meal order app

main.py

 from kivy.app import App
 from kivy.modules import inspector # For inspection.
 from kivy.core.window import Window # For inspection.
+from kivy.properties import BooleanProperty, NumericProperty
 
 __app_package__ = 'edu.unl.cse.soft161.order'
 __app__ = 'Order Meal'
@@ -12,6 +13,21 @@ class OrderApp(App):
     def build(self):
         inspector.create_inspector(Window, self) # For inspection (press control-e to toggle).
 
+    price = NumericProperty(11.00)
+    cheese_price = NumericProperty(0.00)
+
+    def meat_topping(self):
+        self.price += 1.75
+
+    def topping(self):
+        self.price += 1.25
+
+    def update_cheese(self):
+        if self.root.ids.cheese_slider.value > 50:
+            self.cheese_price = 1.50
+        else:
+            self.cheese_price = 0.00
+
 
 if __name__ == '__main__':
     app = OrderApp()

order.kv

 BoxLayout:
     orientation: 'vertical'
     Label:
-        text: '[Your meal-ordering GUI here]'
+        text: 'Online Pizza Order'
+        size_hint: (1, 0.25)
+        color: (1, 0, 0, 1)
+        font_size: '32sp'
+    BoxLayout:
+        orientation: 'vertical'
+        Label:
+            text: 'Cheese'
+        BoxLayout:
+            orientation: 'horizontal'
+            Label:
+                text: 'Less'
+            Slider:
+                range: (0, 100)
+                value: 50
+                id: cheese_slider
+                on_value_pos: app.update_cheese()
+            Label:
+                text: 'More'
+        Label:
+            id: cheese_label
+            text: str(int(cheese_slider.value)) + '%'
+    BoxLayout:
+        orientation: 'vertical'
+        size_hint: (1, 0.3)
+        Label:
+            text: 'Sauce'
+            font_size: '24sp'
+        BoxLayout:
+            orientation: 'vertical'
+            BoxLayout:
+                orientation: 'horizontal'
+                CheckBox:
+                    group: 'sauce'
+                Label:
+                    text: 'Marinara'
+            BoxLayout:
+                orientation: 'horizontal'
+                CheckBox:
+                    group: 'sauce'
+                Label:
+                    text: 'Barbecue'
+    BoxLayout:
+        orientation: 'vertical'
+        Label:
+            text: 'Toppings'
+            font_size: '24sp'
+        BoxLayout:
+            orientation: 'horizontal'
+            Button:
+                on_press: app.meat_topping()
+                text: 'Pepperoni'
+        BoxLayout:
+            orientation: 'horizontal'
+            Button:
+                on_press: app.topping()
+                text: 'Pineapple'
+        BoxLayout:
+            orientation: 'horizontal'
+            Button:
+                on_press: app.topping()
+                text: 'Mushrooms'
+        BoxLayout:
+            orientation: 'horizontal'
+            Button:
+                on_press: app.topping()
+                text: 'Olives'
+        BoxLayout:
+            orientation: 'horizontal'
+            Button:
+                on_press: app.meat_topping()
+                text: 'Bacon'
+    BoxLayout:
+        orientation: 'horizontal'
+        size_hint: (1, 0.25)
+        BoxLayout:
+            Label:
+                text: '$' + str(app.price + app.cheese_price)
+            Button:
+                text: 'Order Now'
+                font_size: '18sp'
+                color: (0.25, 0.5, 1, 1)