python-entry widget 位置更改不会发生并且标签创建问题

Question

代码如下所示，但未重新定位条目小部件位置，也未创建标签。在输入此代码之前 [ e1.grid(row=1,column=1) ] 程序工作正常，输入代码后不工作，如何处理这个问题..该程序是try :import tkinter as tk # Python 3except :import Tkinter as tk # Python 2def update_sum() :# Sets the sum of values of e1 and e2 as val of e3try :    sum_tk.set((float(e1_tk.get().replace(' ', '')) + float(e2_tk.get().replace(' ', ''))))except :    passroot.after(10, update_sum) # reschedule the eventreturnroot = tk.Tk()root.geometry('850x450')e1_tk = tk.StringVar(root) # Initializes a text variable of tk to use to get e1's val.e2_tk = tk.StringVar(root) # Initializes a text variable of tk to use to get e2's val.sum_tk = tk.StringVar(root) # Initializes a text variable of tk to use to set e3's val.# Entriese1 = tk.Entry(root, textvariable = e1_tk)e1.grid(row=1,column=1)e2 = tk.Entry(root, textvariable = e2_tk)e2.grid(row=1,column=2)e3 = tk.Entry(root, textvariable = sum_tk)e3.grid(row=1,column=3)e1=Label(root,text="SL")e1.grid(row=1,column=0)e1.pack()e2.pack()e3.pack()# Will update the sum every second 10 ms = 0.01 second it takes ms as arg.root.after(10, update_sum)root.mainloop()提前致谢..

Answer 1

您对 2 个小部件使用相同的变量并在其上使用网格函数

Grid 和 pack 是两个内置布局管理器，包括 place

我们只能在单个元素上使用其中之一

在您的程序中，您正在打包e1、e2、e3并尝试为它们提供网格布局。

此外，您还使用了e1.grid()两次不同的列值。

try :

    import tkinter as tk # Python 3

except :

    import Tkinter as tk # Python 2

def update_sum() :

# Sets the sum of values of e1 and e2 as val of e3

    try :

        sum_tk.set((float(e1_tk.get().replace(' ', '')) + float(e2_tk.get().replace(' ', ''))))

    except :

        pass

    root.after(10, update_sum) # reschedule the event

    return

root = tk.Tk()

root.geometry('850x450')

e1_tk = tk.StringVar(root) # Initializes a text variable of tk to use to get e1's val.

e2_tk = tk.StringVar(root) # Initializes a text variable of tk to use to get e2's val.

sum_tk = tk.StringVar(root) # Initializes a text variable of tk to use to set e3's val.

# Entries

e1 = tk.Entry(root, textvariable = e1_tk)

e1.grid(row=1,column=1)

e2 = tk.Entry(root, textvariable = e2_tk)

e2.grid(row=1,column=2)

e3 = tk.Entry(root, textvariable = sum_tk)

e3.grid(row=1,column=3)

e4=tk.Label(root,text="SL")

e4.grid(row=1,column=0)

# Will update the sum every second 10 ms = 0.01 second it takes ms as arg.

root.after(10, update_sum)

root.mainloop()