casher.py

from guizero import App, Box, PushButton, Text, ListBox
import sys
import json

cart = dict()
total = 0

def update_cart_list(l):
    global total, listbox
    result = list()
    listbox.clear()
    total = 0
    for i,c in l.items():
        subtotal = c * int(items[i]['price'])
        total = total + subtotal
        listbox.append(items[i]['short'] + ' x ' + str(c) + "  ￥" + str(subtotal))
    update_total()

def update_total():
    global total_label
    total_label.clear()
    total_label.append("合計" + str(total))

def item_clicked(c):
    if not c in cart:
        cart[c] = 1
    else:
        cart[c] = cart[c] + 1
    update_cart_list(cart)

def clear_cart():
    global cart, total, listbox
    cart = dict()
    total = 0
    listbox.clear()
    update_total()

def do_nothing():
    sys.exit()

with open('items.json') as f:
    items = json.loads(f.read())

app = App(title="EjeCasher")
app.full_screen = True

itembox = Box(app, layout="grid", width="fill", align="left")
cartbox = Box(app, width="fill", align="left")
button = list()

for c,i in enumerate(items):
    x = c % 3
    y = int(c / 3) * 3
    button.append(PushButton(itembox, grid=[x,y], image=i['image'], command=item_clicked, args=[c]))
    Text(itembox, grid=[x,y+1], text=i['name'])
    Text(itembox, grid=[x,y+2], text="￥"+i['price'])

Text(cartbox, text="選択した商品:")
listbox = ListBox(cartbox, width="fill", items=[])
clear_button = PushButton(cartbox, width="fill", text="キャンセル", command=clear_cart)
total_label = Text(cartbox, text="合計: ")
total_label.text_size = 20
pay_button = PushButton(cartbox, width="fill", text="購入", command=do_nothing)

app.display()