输入Entry小部件后如何更新IntVar？

Question

我想制作一个余额条目小部件，它将仅接受整数，并且值必须为20-5000。我仅制定了int准则，但是我不知道如何处理20-5000的值限制。

我试图制作一个执行if语句的“开始游戏按钮”，但它不会更新我在输入框中键入的值，即使它的按钮具有it命令功能，它在开始时默认情况下仍为0。

如果有人知道解决方案，请给我提示！

@EDIT：下面是我的全部代码！

# Import modules
import tkinter as tk


class MainApplication(tk.Frame):
    def __init__(self, master):
        super().__init__(master)
        self.master = master
        self.window_geom = WindowsProperties(self.master)
        self.master.withdraw()

    # Opening first window as a Toplevel
    def new_window(self):
        self.first_window = tk.Toplevel(self.master)
        self.app = FirstWindow(self.first_window)

class FirstWindow(tk.Frame):

    def __init__(self, master):
        super().__init__(master)

        # Create all root objects:
        self.window_geom = WindowsProperties(self.master)
        self.root_buttons = FirstWindowButtons(self.master)
        self.root_entry = FirstWindowEntry(self.master)
        self.root_labels = FirstWindowLabels(self.master)

class FirstWindowEntry(tk.Frame):
    # Class contain every button on a first screen, with its functions.
    def __init__(self, master):
        super().__init__(master)

        self.player_name = tk.StringVar()
        self.vcmd1 = self.register(self.callback_name)
        self.player_name_entry = tk.Entry(
            master,
            textvariable=self.player_name,
            font=("Verdana", 12),
            width=15,
            validate="all",
            validatecommand=(self.vcmd1, "%P"),
        )
        self.player_name_entry.place(x=700, y=230)
        self.player_name_entry.focus()

        self.player_balance = tk.IntVar()
        self.vcmd2 = self.register(self.callback_balance)
        self.player_balance_entry = tk.Entry(
            master,
            textvariable=self.player_balance,
            font=("Verdana", 12),
            width=15,
            validate="all",
            validatecommand=(self.vcmd2, "%P"),
        )
        self.player_balance_entry.place(x=700, y=270)

    # Method which validate if entered str is digit in Balance Entry
    def callback_balance(self, P):
        if len(P) <= 5 and (str.isdigit(P) or P == ""):
            return True
        else:
            return False

    # Method which validate if entered str is not longer than 15 characters in Player name Entry
    def callback_name(self, P):
        if len(P) <= 15:
            return True
        else:
            return False


class FirstWindowButtons(FirstWindowEntry):
    # Class contain every button on a first screen, with its functions.
    def __init__(self, master):
        super().__init__(master)

        self.start_button = tk.Button(master, command=self.start_button_func)
        self.start_button_img = tk.PhotoImage(
            file="C:/Users/rjg5by/Scripts/venv/blackjack/start_button_img.png"
        )
        self.start_button.config(
            image=self.start_button_img,
            borderwidth=-10,
            bg="black",
            activebackground="black",
        )
        self.start_button.place(x=630, y=500)

        self.quit_button = tk.Button(master, command=self.quit_button_func)
        self.quit_button_img = tk.PhotoImage(
            file="C:/Users/rjg5by/Scripts/venv/blackjack/quit_button_img.png"
        )

        self.quit_button.config(
            image=self.quit_button_img,
            borderwidth=-10,
            bg="black",
            activebackground="black",
        )
        self.quit_button.place(x=800, y=500)

    def start_button_func(self):
        print(self.player_balance.get())
        if self.player_balance.get() >= 20:
            root.deiconify()  # Main game play windows appears
            self.master.destroy()  # Exit of first window
        else:
            print("Not enough ")

    def quit_button_func(self):
        root.destroy()


class FirstWindowLabels(tk.Frame):
    # Class contain every button on a root screen, with its functions.
    def __init__(self, master):
        super().__init__(master)

        self.player_name_label = tk.Label(
            master, text="Player name:", font=("Verdana", 14)
        )
        self.player_name_label.config(fg="white", bg="black")
        self.player_name_label.place(x=540, y=230)

        self.player_balance_label = tk.Label(
            master, text="Balance:", font=("Verdana", 14)
        )
        self.player_balance_label.config(fg="white", bg="black")
        self.player_balance_label.place(x=540, y=270)


class WindowsProperties(tk.Frame):
    # Class define windows main properties.
    def __init__(self, master):
        super().__init__(master)

        self.width_of_window = 980
        self.height_of_window = 604
        self.screen_width = self.master.winfo_screenwidth()
        self.screen_height = self.master.winfo_screenheight()
        self.x_coordinate = int((self.screen_width / 2) - (self.width_of_window / 2))
        self.y_coordinate = int(
            (self.screen_height / 2) - (self.height_of_window / 2) - 30
        )
        self.master.geometry(
            f"{self.width_of_window}x{self.height_of_window}+{self.x_coordinate}+{self.y_coordinate}"
        )

        self.master.resizable(width=False, height=False)  # Resizable of a window

        self.master.title("Blackjack")  # Title of an application


if __name__ == "__main__":
    root = tk.Tk()
    app = MainApplication(root)
    MainApplication.new_window(root)
    root.mainloop()

第二编辑：

@Mike-SMT非常感谢您的帮助！我按照您的指示修改了我的代码，发现我需要自我介绍。映像变量以使其工作。在所有的更正代码如下所示之后，我有一个关于从MainApplication类获取窗口属性的问题，我在其中放置了“ window_properties（）”方法并在TopLevel窗口中运行它，但它没有获得其属性，您是否有一些想法，我怎么能得到它而不必将相同的代码放在顶层风？ （没有方法，它也不会得到适当的大小）

还，请告诉我现在如何在MainApp类中获取'self.player_name'和'self.player_balance'值？

解决方案： 我已经将这行FirstWindow（）更改为self.first_window = FirstWindow（）

现在我可以通过self.first_window.player_balance来获取此值，并且现在可以使用了。

编辑：我减少了不必要的代码。

import tkinter as tk

class MainApplication(tk.Tk):
    def __init__(self):
        super().__init__()

        self.window_properties()
        self.withdraw()
        self.new_window()

    def new_window(self):
        FirstWindow()

    def window_properties(self):
        width_of_window = 980
        height_of_window = 604
        screen_width = self.winfo_screenwidth()
        screen_height = self.winfo_screenheight()
        x_coordinate = int((screen_width / 2) - (width_of_window / 2))
        y_coordinate = int((screen_height / 2) - (height_of_window / 2) - 30)
        self.geometry(
            f"{width_of_window}x{height_of_window}+{x_coordinate}+{y_coordinate}"
        )

class FirstWindow(tk.Toplevel):

    def __init__(self):
        super().__init__()

        # Defining variables
        self.player_name = tk.StringVar()
        self.player_balance = tk.IntVar()

        self.master.window_properties()

        self.vcmd1 = self.register(self.callback_name)
        player_name_entry = tk.Entry(
            self,
            textvariable=self.player_name,
            font=("Verdana", 12),
            width=15,
            validate="all",
            validatecommand=(self.vcmd1, "%P"),
        )
        player_name_entry.place(x=700, y=230)
        player_name_entry.focus()

        self.vcmd2 = self.register(self.callback_balance)
        player_balance_entry = tk.Entry(
            self,
            textvariable=self.player_balance,
            font=("Verdana", 12),
            width=15,
            validate="all",
            validatecommand=(self.vcmd2, "%P"),
        )
        player_balance_entry.place(x=700, y=270)


        # Player balance Label widget
        player_balance_label = tk.Label(self, text="Balance:", font=("Verdana", 14))
        player_balance_label.config(fg="white", bg="black")
        player_balance_label.place(x=540, y=270)

        # Information about min/max balance Label widget
        self.min_max_label = tk.Label(
            self,
            text="The balance should be between 20 and 5000 $.",
            font=("Verdana", 10),
        )
        self.min_max_label.config(fg="white", bg="black")
        self.min_max_label.place(x=540, y=310)


        start_button = tk.Button(self, command=self.start_button_func)
        start_button.config(
            borderwidth=-10,
            bg="black",
            activebackground="black",
        )
        start_button.place(x=630, y=500)

        quit_button = tk.Button(self, command=self.quit_button_func)
        quit_button.config(borderwidth=-10, bg="black", activebackground="black"
        )
        quit_button.place(x=800, y=500)

    # Method which validate if entered str is digit in Balance Entry
    def callback_balance(self, P):
        if len(P) <= 5 and (str.isdigit(P) or P == ""):
            return True
        else:
            return False

    # Method which validate if entered str is not longer than 15 characters in Player name Entry
    def callback_name(self, P):
        if len(P) <= 15:
            return True
        else:
            return False

    # This method checks if player typed a name, than checks if balance is 20-5000. If all statement are ok, move to main play game window
    def start_button_func(self):
        if self.player_name.get() == "":
            self.min_max_label.config(
                fg="red", bg="black", text="Please type your name."
            )
        elif self.player_balance.get() < 20:
            self.min_max_label.config(
                fg="red",
                bg="black",
                text="Please correct your balance value. It should be at least 20 $.",
            )
        elif self.player_balance.get() > 5000:
            self.min_max_label.config(
                fg="red",
                bg="black",
                text="Please correct your balance value. Maximum is 5000 $.",
            )
        else:
            self.master.deiconify()  # Main game play windows appears
            self.destroy()  # Exit of first window

    # Quiting whole game button
    def quit_button_func(self):
        self.master.destroy()


if __name__ == "__main__":
    MainApplication().mainloop()

Answer 1

我找到了解决我问题的方法。问题是我以错误的顺序创建对象。我做了一个按钮对象（定义平衡是否正确），然后做了一个输入对象，这是不正确的！

正确的代码应该像这样：

self.window_geom = WindowsProperties(self.master)
self.root_entry = FirstWindowEntry(self.master)   # <-- Create before buttons!
self.root_buttons = FirstWindowButtons(self.master)
self.root_labels = FirstWindowLabels(self.master)

Answer 2

您在这里所做的事情太过分了。通过将所有内容分成不同的类，您将更难获得不同类中的变量。尽管可能的话，我会在一个类而不是多个类中构建您的顶部窗口。

那就是说，我还将构建您的主应用程序以继承自Tk（）而不是Frame（）。

我已删除您的图像，以测试以下示例的功能。

请考虑以下重新编写的代码，如果您有任何疑问，请告知我：

import tkinter as tk


class MainApplication(tk.Tk):
    """Main class of Blackjack Game.
    Importing game play classes and window properties
    """
    def __init__(self):
        super().__init__()
        self.title("Blackjack")
        width_of_window = 980
        height_of_window = 604
        screen_width = self.winfo_screenwidth()
        screen_height = self.winfo_screenheight()
        x_coordinate = int((screen_width / 2) - (width_of_window / 2))
        y_coordinate = int((screen_height / 2) - (height_of_window / 2) - 30)
        self.geometry(f"{width_of_window}x{height_of_window}+{x_coordinate}+{y_coordinate}")
        self.resizable(width=False, height=False)
        tk.Label(self, text='bg image').place(x=0, y=0)
        self.withdraw()
        self.new_window()

    def new_window(self):
        FirstWindow()


class FirstWindow(tk.Toplevel):
    """First window class.
    Contains player name and balance entry, label. Start/Quit buttons
    """
    def __init__(self):
        super().__init__()
        self.player_name = tk.StringVar()
        self.player_balance = tk.IntVar()
        tk.Label(self,  text='bg image').place(x=0, y=0)
        self.vcmd1 = self.register(self.callback_name)
        player_name_entry = tk.Entry(self, textvariable=self.player_name, font=("Verdana", 12),
                                     width=15, validate="all", validatecommand=(self.vcmd1, "%P"))
        player_name_entry.place(x=700, y=230)
        player_name_entry.focus()
        self.vcmd2 = self.register(self.callback_balance)
        tk.Entry(self, textvariable=self.player_balance, font=("Verdana", 12), width=15, validate="all",
                 validatecommand=(self.vcmd2, "%P")).place(x=700, y=270)

        tk.Button(self, command=self.start_button_func,  text='start btn').place(x=630, y=500)

        tk.Button(self, command=self.quit_button_func, text='quit btn').place(x=800, y=500)
        tk.Label(self, text="Player name:", font=("Verdana", 14)).place(x=540, y=230)
        tk.Label(self, text="Balance:", font=("Verdana", 14)).place(x=540, y=270)

    def callback_balance(self, p):
        if len(p) <= 5 and (str.isdigit(p) or p == ""):
            return True
        else:
            return False

    def callback_name(self, p):
        if len(p) <= 15:
            return True
        else:
            return False

    def start_button_func(self):
        print(self.player_balance.get())
        if self.player_balance.get() >= 20:
            self.master.deiconify()
            self.destroy()
        else:
            print("Not enough ")

    def quit_button_func(self):
        self.destroy()


if __name__ == "__main__":
    MainApplication().mainloop()