如何在Tkinter/SQL中基于另一个变量选择一个变量

Question

我的问题是我想要第二个下拉菜单"操作1"；以基于在"；Pink1〃；。数据库PROD_MachineOperations包括机器名称和操作。但是PROD_Machine也包括相同的Machines。

其概念是，我在SQL数据库PROD_machines中有机器的名称，这是第一个选择，然后根据所选的机器，它将在PROD_MachineOperations数据库中为该机器列出的操作列为machine_NAME，OPERATION

from tkinter import *
from tkinter import ttk
import tkinter as tk
import pyodbc
DEFAULT_ENCODING = 'utf-8'
ws=Tk()
ws.title('Test')
ws.geometry('150x100')
ws['bg'] = '#26658f'
ws.resizable(False, False)
con1 = pyodbc.connect('DRIVER={ODBC Driver 17 for SQL Server};SERVER=192.168.1.8;DATABASE=HUT;UID=######;PWD=######')

cur2 = "SELECT [Machine] FROM PROD_Machines"
cur1 = con1.cursor()
cur1.execute(cur2)
proov1 = [x[0] for x in cur1.fetchall()]
def callback_pink(event):
"""Callback event called by combobox 'Pink1' via Pink1.bind("<<ComboboxSelected>>", callback_pink)"""
con1 = pyodbc.connect('DRIVER={ODBC Driver 17 for SQL Server};SERVER=192.168.1.8;DATABASE=HUT;UID=######;PWD=#######')
cur3 = "SELECT [Operation] FROM PROD_MachineOperations WHERE [Machine] LIKE (?)"
val2 = (event.widget.get())
cur4 = con1.cursor()
cur4.execute(cur3,val2)
proov2 = [x[0] for x in cur4.fetchall()]
Operatsioon1["values"] = proov2
Operatsioon1.current(len(Operatsioon1["values"])-1)
Operatsioon1.current(0)
cur3 = "SELECT [Operator] FROM PROD_MachineOperators WHERE [Machine] LIKE (?)"
val2 = (event.widget.get())
cur4 = con1.cursor()
cur4.execute(cur3,val2)
proov2 = [x[0] for x in cur4.fetchall()]
Operaator1["values"] = proov2
Operaator1.current(len(Operaator1["values"])-1) 
Operaator1.current(0)


Pink_entry = tk.StringVar()
Pink1 = ttk.Combobox(ws, textvariable=Pink_entry, width = 17)
Pink1['values'] = proov1
Pink1['state'] = 'readonly'
Pink1.grid(row=4,column=2,padx=(10, 10))
Pink1.bind("<<ComboboxSelected>>", callback_pink, callback_pink)

Operatsioon_entry = tk.StringVar()
Operatsioon1 = ttk.Combobox(ws, textvariable=Operatsioon_entry, width = 17)
Operatsioon1['state'] = 'readonly'
Operatsioon1.grid(row=6,column=5,padx=(10, 10))
Operaator_entry = tk.StringVar()
Operaator1 = ttk.Combobox(ws, textvariable=Operaator_entry, width = 17)
Operaator1['state'] = 'readonly'
Operaator1.grid(row=4,column=3,padx=(10, 10))
ws.mainloop()

Answer 1

使用事件和回调。例如：

from tkinter import *
from tkinter import ttk
import tkinter as tk
# import pyodbc
DEFAULT_ENCODING = 'utf-8'
ws=Tk()
ws.title('Haapsalu Uksetehas')
ws.geometry('150x100')
ws['bg'] = '#26658f'
ws.resizable(False, False)

def callback_pink(event):
"""Callback event called by combobox 'Pink1' via Pink1.bind("<<ComboboxSelected>>", callback_pink)"""
# here you get the currently selected value. You can use this function for any combobox
selected_value = event.widget.get()
# here you do your SQL query based on selected_value; selected_value holds your machine name; for example:
# filter = selected_value
# sql = "SELECT property FROM machine WHERE machine LIKE ?"
# param = f"%{filter}%"
# rows = cur1.execute(sql, param).fetchall()
# here i simulate your received results
rows = ["turn on", "turn off", "restart", "calibrate"]
# here i replace the values of the second list with a list of tuples with joined strings of selected_value and rows
Operatsioon1["values"] = [(f"{selected_value}, {row}",) for row in rows]
# Operatsioon1.current(len(Operatsioon1["values"])-1)  # select the last available value
Operatsioon1.current(0)  # select the first available value

# commented so i can test it
# con1 = pyodbc.connect('DRIVER={ODBC Driver 17 for SQL Server};SERVER=192.168.1.8;DATABASE=HUT;UID=######;PWD=#####')
# cur2 = "SELECT [Machine] FROM PROD_Machines"
# cur1 = con1.cursor()
# cur1.execute(cur2)
# proov1 = [x[0] for x in cur1.fetchall()]
# this simulates the return from your PROD_MachineOperations table
proov1 = ["Machine 1", "Machine 2", "Machine 3", "Machine 4"]

Pink_entry = tk.StringVar()
Pink1 = ttk.Combobox(ws, textvariable=Pink_entry, width = 17)
Pink1['values'] = proov1
Pink1['state'] = 'readonly'
Pink1.grid(row=0, column=0, padx=(10, 10))
Pink1.bind("<<ComboboxSelected>>", callback_pink)
cur3 = "SELECT [Operation] FROM PROD_MachineOperations WHERE [Machine] LIKE (?)"
val2 = (Pink_entry.get())
# this now happens in your callback function
# cur4 = con1.cursor()
# cur4.execute(cur3,val2)
# proov2 = [x[0] for x in cur4.fetchall()]
# Operatsioon_entry = tk.StringVar()  # this doesnt do anything
Operatsioon1 = ttk.Combobox(ws, width=17)  # removed textvar=.. here
Operatsioon1['state'] = 'readonly'
Operatsioon1.grid(row=1, column=0, padx=(10, 10))
ws.mainloop()