为什么我必须多次点击按钮?tkinter gui

Question

嗨，我已经使用tkinter创建了一个GUI，它接受来自用户的输入。我已经创建了自己的状态检查和"拼写"检查，以确保用户只输入可接受的值。但每次我输入这些值时，它都会让用户在输出屏幕出现之前多次点击提交按钮。这是因为我使用了多个函数吗?还有别的办法吗?

def Search():
    global E1, E2, E3, E4, file
    def PresenceValidation():
        if E1.get() ==(''):
            root2=Tk()
            errortext = Label(root2, text = "Please enter eye colour")  
            errortext.pack()
        elif E2.get() ==(''):
            root2=Tk()
            root2.configure(bg="white")
            errortext = Label(root2, text = "Please enter age")
            errortext.pack()
        elif E3.get() ==(''):
            root2=Tk()
            root2.configure(bg="white")
            errortext = Label(root2, text = "Please enter hair colour")
            errortext.pack()
        elif E4.get() ==(''):
            root2=Tk()
            root2.configure(bg="white")
            errortext = Label(root2, text = "Please enter shoesize")
            errortext.pack()            
        else:
            button = Button(root, text = "Submit information", command=SpellCheck)
            button.grid(row=3, column=2, padx = 5)
    def SpellCheck():
        if E1.get().lower() not in ('blue', 'brown', 'green'):
            root2=Tk()
            root2.configure(bg="white")
            errortext = Label(root2, text = "Please enter eye colour")
            message= Label(root2, text = "Blue, Brown or Green")
            errortext.pack()
            message.pack()
        elif E2.get().lower()  not in ('10-20', '20-30', '30-40','40+'):
            root2=Tk()
            root2.configure(bg="white")
            errortext = Label(root2, text = "Please enter a valid age group")
            message=Label(root2, text = "10-20, 20-30, 30-40 or 40+")
            errortext.pack()
            message.pack()
        elif E3.get().lower()  not in ('Brown', 'Black', 'Blonde', 'Auburn'):
            root2=Tk()
            root2.configure(bg="white")
            errortext = Label(root2, text = "Please enter a valid hair colour")
            message = Label(root2, text = "Brown, Black, Blonde or Auburn")
            errortext.pack()
            message.pack()
        elif E4.get().lower() not in ('1', '2', '3','4','5','6','7','8+'):
            root2=Tk()
            root2.configure(bg="white")
            errortext = Label(root2, text = "Please enter a valid shoesize")
            message = Label(root2, text = "1,2,3,4,5,6,7,8+")
            errortext.pack()
            message.pack()         
        else:
            submitbutton = Button(window, text = "Submit information", command=Submit)
            submitbutton.grid(row=3, column=2, padx = 5)   

    root = Tk()
    root.title ("Search for matches")

    #text that will be shown to the user
    root.configure(bg="white")
    Label(root, text="Please enter eye colour").grid(row=0)
    Label(root, text="Please enter age").grid(row=1)
    Label(root, text="Please enter hair colour").grid(row=2)
    Label(root, text="Please enter shoesize").grid(row=3)

    #Create user entry points
    E1= Entry(root)
    E2= Entry(root)
    E3= Entry(root)
    E4= Entry(root)
    # locating input boxes to area on the screen
    E1.grid(row=0, column=1)
    E2.grid(row=1, column=1)
    E3.grid(row=2, column=1)
    E4.grid(row=3, column=1)


    submitbutton = Button(window, text = "Submit information", command=PresenceValidation)
    submitbutton.grid(row=3, column=2, padx = 5)
    def Quit():
    window.destroy()
    quitbton = Button (window, text ="QUIT", command=Quit)
    quitbton.grid(row=3, column=3, padx=5)

Answer 1

您可以重写此代码以省略大量代码，并且仍然使其按您想要的方式运行。你得到多个按钮的原因是因为你做了多个按钮。三个，如果我全部算上的话。初始的Submit按钮应该调用一个函数来验证字段，如果遇到不正确的值，则跳出循环。您还可以使用Messagebox来提示用户错误在哪里。

如果您不添加Messagebox并希望保持原样，则应该将root2实例更改为顶层小部件，以避免创建两个Tkinter实例。这也可能导致意想不到的结果。

这里有一个简单的例子，告诉你如何检查你的状态:

from tkMessageBox import showwarning
def PresenceValidation():
    #Make dictionary to hold values
    values = {'Eye color': E1.get(),
              'Age': E2.get(),
              'Hair': E3.get(),
              'Shoesize': E4.get()
              }
    #Iterate over dictionary to check for empty items
    for k,v in values.iteritems():
        if v == '':
            showwarning('Empty Value Alert',    #Create alert message
                        k + ' needs a value')   #for the first empty value,
            break                               #and break out of the loop

Answer 2

问题的一部分是您正在创建多个根窗口。Tkinter并不是这样设计的。如果需要更多的窗口，创建Toplevel的实例。