擅长:python、mysql、java
<pre><code>import tkinter as tk
brands = ["Bugatti","VW","Opel","Porsche"]
models = [["Veyron","Chiron"],
["Golf","Passat","Polo","Caddy"],
["Insignia","Corsa","Astra"],
["Taycan","Cayenne","911"]]
root = tk.Tk()
canvas = tk.Canvas(root, height=500, width= 500, bg="white")
canvas.pack()
tkvar = tk.StringVar(root)
tkvar.set('Choose')
tkvar2 = tk.StringVar(root)
tkvar2.set('Model')
popupMenu1 = tk.OptionMenu(canvas, tkvar, *brands)
popupMenu1.pack()
popupMenu2 = tk.OptionMenu(canvas, tkvar2, [])
popupMenu2.pack()
def change_dropdown(*args):
print("Chosen brand " + tkvar.get())
for i in range(len(brands)):
if tkvar.get() == brands[i]:
popupMenu2["menu"].delete(0, "end")
for item in models[i]:
popupMenu2['menu'].add_command(label=item, command=tk._setit(tkvar2, item))
tkvar.trace('w', change_dropdown)
root.mainloop()
</code></pre>