Update app.py

app.py

@@ -1,6 +1,7 @@
-! pip install gradio       # Installing Gradio interface
+# If running in a notebook:
+# !pip install gradio
+
 import gradio as gr
-from gradio import Blocks, Number, Button, Textbox
 
 Inventory = [
     (1, "Apples", 250),
@@ -12,126 +13,123 @@ Inventory = [
 
 Your_Cart = []
 
-def add_item_to_cart(item_id, Inventory):
-    """
-    Adds an item from the Inventory to the shopping cart.
-    """
+def add_item_to_cart(item_id, inventory):
+    """Adds an item from the inventory to the shopping cart."""
     try:
-        item = Inventory[item_id - 1]
+        item = inventory[item_id - 1]
         Your_Cart.append(item)
-        return f"{'>'*10} The item '{item[1]}' has been added to the cart. {'<'*10} \n\n"
-    except IndexError:
-        return f"Invalid item ID: {item_id}"
+        return f"{'>'*10} The item '{item[1]}' has been added to the cart. {'<'*10}\n\n"
+    except (IndexError, TypeError):
+        return f"Invalid item ID: {item_id}\n\n"
 
 def remove_item(cart_index, cart_items):
-    """
-    Removes an item from the shopping cart.
-    """
+    """Removes an item from the shopping cart by displayed index."""
     try:
         removed_item = cart_items.pop(cart_index - 1)
-        return f"{'>'*10} The item '{removed_item[1]}' has been removed from the cart, and your shopping cart has been updated. {'<'*10} \n\n"
-    except IndexError:
-        return "Invalid cart index or cart is empty."
+        return f"{'>'*10} The item '{removed_item[1]}' has been removed from the cart, and your shopping cart has been updated. {'<'*10}\n\n"
+    except (IndexError, TypeError):
+        return "Invalid cart index or cart is empty.\n\n"
+
+def display_cart(cart_items):
+    """Displays the items in the shopping cart (stable, one line per item in cart order)."""
+    if not cart_items:
+        return f"{'>'*10} Your cart is empty !!!, Why not buy Fruits from us ... {'<'*10}\n\n"
+
+    cart_str = ""
+    cart_str += "+" * 70 + "\n"
+    cart_str += f"{'Your Cart'.center(60)}\n"
+    cart_str += "+" * 70 + "\n"
+    cart_str += f"{'Index':<10} {'Name':<20} {'Price Per KG':<15}\n"
+    cart_str += "-" * 70 + "\n"
 
-def display_cart(Your_Cart):
-    """
-    Displays the items in the shopping cart.
-    """
-    if Your_Cart:
-        cart_str = ""  # Initialize an empty string to store the cart display
-        cart_str += "+" * 50 + "\n"
-        cart_str += f"{'Your Cart'.center(40)}" + "\n"
-        cart_str += "+" * 50 + "\n"
-        cart_str += f"{'Index':<10} {'Name':<20} {'Quantity':<10} {'Price Per KG':<10}" + "\n"
-        cart_str += "-" * 50 + "\n"
-        unique_items = set(Your_Cart)  # Get unique items in the cart
-        total_cost = 0
-        for index, item in enumerate(unique_items):
-            quantity = Your_Cart.count(item)
-            price_per_kg = item[2]
-            total_price = price_per_kg * quantity
-            cart_str += f"{index+1:<10} {item[1]:<20} {quantity:<10} ${total_price:<10.2f}" + "\n"
-            total_cost += total_price
-        cart_str += "-" * 50 + "\n"
-        cart_str += f"{'Total Cost':<40} ${total_cost:<10.2f}"  # Display grand total
-        return cart_str  # Return the string representation of the cart
-    else:
-        return f"{'>'*10} Your cart is empty !!!, Why not buy Fruits from us ... {'<'*10} \n\n"
+    total = 0
+    for idx, item in enumerate(cart_items, start=1):
+        cart_str += f"{idx:<10} {item[1]:<20} ${item[2]:<15.2f}\n"
+        total += item[2]
+
+    cart_str += "-" * 70 + "\n"
+    cart_str += f"{'Total Cost':<32} ${total:<10.2f}\n"
+    return cart_str
 
 def total_cost(cart_items):
-    """
-    Calculates the total cost of all items in the shopping cart.
-    """
-    total = 0
-    for item in cart_items:
-        total += item[2]  # Assuming quantity is 1 for now
-    return f"~"*40 + "\n" + f"Total cost: {total}".center(40) + "\n" + "~"*40 + "\n\n"
+    """Calculates total cost of all items in the cart."""
+    total = sum(item[2] for item in cart_items)
+    return "~" * 40 + "\n" + f"Total cost: {total}".center(40) + "\n" + "~" * 40 + "\n\n"
 
 def gradio_interface(item_id, cart_index):
     """
-    Handles adding/removing items, displaying the cart, and calculating the total cost.
-
-    Args:
-        item_id (int): The product ID to add to the cart (if any).
-        cart_index (int): The product ID to remove from the cart (if any).
-
-    Returns:
-        tuple: A tuple containing the updated cart display, add message, remove message, and total cost.
+    Handles adding/removing items, displaying the cart, and calculating total cost.
     """
+    # Convert inputs (Gradio Numbers are floats)
+    def to_int(x):
+        try:
+            if x is None:
+                return 0
+            return int(x)
+        except (ValueError, TypeError):
+            return 0
+
+    item_id = to_int(item_id)
+    cart_index = to_int(cart_index)
 
-    # Add item
     add_msg = ""
-    if item_id:
+    if item_id > 0:
         add_msg = add_item_to_cart(item_id, Inventory)
 
-    # Remove item
     remove_msg = ""
-    if cart_index:
+    if cart_index > 0:
         remove_msg = remove_item(cart_index, Your_Cart)
 
-    # Display the cart and calculate total cost
     cart_display = display_cart(Your_Cart)
     cost_msg = total_cost(Your_Cart)
 
     return cart_display, add_msg, remove_msg, cost_msg
 
-# Gradio interface creation
 def launch_gradio():
-    """
-    Launches the Gradio interface for the fruit shopping cart system.
-    """
-
     with gr.Blocks() as demo:
         gr.Markdown("### Fruit Shopping Cart System")
+        gr.Markdown(
+            "Inventory:\n"
+            + "\n".join([f"- {pid}: {name} (${price}/kg)" for pid, name, price in Inventory])
+        )
 
         with gr.Row():
-            item_id_input = gr.Number(label="Enter Product ID to Add to Cart", interactive=True)
-            cart_index_input = gr.Number(label="Enter Index ID to Remove from Cart", interactive=True)
+            item_id_input = gr.Number(label="Enter Product ID to Add to Cart", precision=0)
+            cart_index_input = gr.Number(label="Enter Cart Index to Remove", precision=0)
+
+        # Hidden zero inputs created ONCE (don’t create components inside .click)
+        zero_item = gr.Number(value=0, visible=False, precision=0)
+        zero_cart = gr.Number(value=0, visible=False, precision=0)
 
         with gr.Row():
             add_button = gr.Button("Add to Cart")
             remove_button = gr.Button("Remove from Cart")
+            refresh_button = gr.Button("Refresh Cart View")
 
-        cart_display_output = gr.Textbox(label="Your Cart", interactive=False)
-        add_message_output = gr.Textbox(label="Add Item Message", interactive=False)
-        remove_message_output = gr.Textbox(label="Remove Item Message", interactive=False)
-        total_cost_output = gr.Textbox(label="Total Cost", interactive=False)
+        cart_display_output = gr.Textbox(label="Your Cart", interactive=False, lines=12)
+        add_message_output = gr.Textbox(label="Add Item Message", interactive=False, lines=2)
+        remove_message_output = gr.Textbox(label="Remove Item Message", interactive=False, lines=2)
+        total_cost_output = gr.Textbox(label="Total Cost", interactive=False, lines=4)
 
-        # Add item button click behavior
         add_button.click(
-            gradio_interface,
-            inputs=[item_id_input, gr.Number(visible=False, value=0)],  # Pass a hidden Number component for cart_index
+            fn=gradio_interface,
+            inputs=[item_id_input, zero_cart],
             outputs=[cart_display_output, add_message_output, remove_message_output, total_cost_output]
         )
 
-        # Remove item button click behavior
         remove_button.click(
-            gradio_interface,
-            inputs=[gr.Number(visible=False, value=0), cart_index_input],  # Pass a hidden Number component for item_id
+            fn=gradio_interface,
+            inputs=[zero_item, cart_index_input],
             outputs=[cart_display_output, add_message_output, remove_message_output, total_cost_output]
         )
+
+        refresh_button.click(
+            fn=gradio_interface,
+            inputs=[zero_item, zero_cart],
+            outputs=[cart_display_output, add_message_output, remove_message_output, total_cost_output]
+        )
+
     demo.launch()
 
-# Run the Gradio interface
 if __name__ == "__main__":
     launch_gradio()