如何將python事件變量傳遞給另一個函數？

Question

我正在構建一個簡單的GUI，並且試圖將事件變量傳遞到已經具有事件變量的另一個函數中時遇到問題。

我試圖在函數“ addNumbs”中使用變量“ sqlItemx”，該變量是“ self.item1”的事件變量。

如何傳遞此變量供以后使用？

我試圖簡單地按照通常的約定傳遞變量，但這對我不起作用。

我的代碼節錄如下：

def listitems(self, event):
    for widget in self.itemFrame.winfo_children():
        widget.destroy()
    searchLettersx = event.widget['text']
    mycursor.execute("SELECT Name FROM inventory WHERE Name LIKE '" + searchLettersx + "%' ")
    myresult = mycursor.fetchall()
    rcount = 0
    ccount = 0
    for y in myresult:
        self.item1 = tk.Button(self.itemFrame, text=y, bg='white', fg='deep sky blue', font=("Helvetica", 18), height='4', width='22')
        self.item1.grid(column=ccount, row=rcount)
        self.item1.bind('<Button-1>', self.addtoCart)
        if rcount >= 5:
            ccount += 1
            rcount = 0
        rcount += 1  

 def addtoCart(self, event):
    win = tk.Toplevel(bg="white")
    win.wm_title("Add to Cart")

    sqlItemx = event.widget['text']

    frame = tk.Frame(win)
    frame.grid()
    self.numpadFrame = tk.Frame(win, pady='20', bg="white")
    self.numpadFrame.grid(column='0', row='2')

    itemLabel = tk.Label(win, text=sqlItemx, bg="white", font=("Helvetica", 18), pady="30")
    itemLabel.grid(row=0, column=0)

    numLabel = tk.Label(win, text="How many? ", bg="white", font=("Helvetica", 18), pady="30", anchor='e', justify='left')
    numLabel.grid(row=1, column=0)

    numbers = ["1", "2", "3", "4" , "5" , "6" , "7" , "8" , "9" , " " , "0" , " "]
    count = 0

    for r in range(4):
        for c in range(3):
            numpad = tk.Button(self.numpadFrame, text=numbers[count], height='4', width='8', bg='white', fg='deep sky blue', font=("Helvetica", 18))
            numpad.grid(row=r+1,column=c)
            numpad.bind('<Button-1>', self.addNumbs)
            count += 1

    finalize = tk.Button(win, text="Submit", height='2', width='14', bg='white', fg='deep sky blue', font=("Helvetica", 18))
    finalize.grid(column='0', row='7', columnspan='4')
    finalize["command"] = win.destroy

def addNumbs(self, event):

    numPadx = event.widget['text']

    sql = "INSERT INTO tempcart (item, count) VALUES (%s, %s)"
    val = ("item", numPadx)
    addtempCart.execute(sql, val)
    mydb.commit()

    gettempCartID.execute("SELECT ID FROM tempcart ORDER BY ID DESC LIMIT 1")
    gettempCartID_result = gettempCartID.fetchall()

    gettempCart.execute("SELECT item, count FROM tempcart")
    gettempCart_result = gettempCart.fetchall()

    for y in gettempCart_result:
        for z in gettempCartID_result: 
            self.cartItem = tk.Label(self.cartFrame, text=y, bg="white", font=("Helvetica", 20))
            self.cartItem.grid(column="0", row=z)

    mydb.commit()

我的最終目標是能夠將此變量的值傳遞到“ addNumbs”中，並將其用作我的MySQL語句的變量“ val”中的值之一。

Answer 1

您不需要通過bind方法將命令附加到按鈕上。 相反，您可以使用command關鍵字參數。

為了傳遞item_type參數，您需要遍歷與創建的每個按鈕相對應的各種參數，並在創建按鈕時將它們包含在函數調用中。

也許是這樣的：

...
list_of_items = [item0, item1, item2, ...]
item_buttons = []   # keep a reference on each button

for y, item in enumerate(list_of_items):
    btn = tk.Button(self.itemFrame, command=lambda item=item: self.addtoCart(item), ...)
    item_buttons.append(btn)
    btn.grid(column=ccount, row=rcount)
...