在 tkinter 中，如何访问在另一个窗口中创建的变量？

Question

我似乎不知道如何在我的应用程序的一个窗口中创建或修改变量，然后在另一个窗口中访问它。另外，如何在 StartPage 中的 spinboxes 上检索选定的值？

这是我正在使用的代码：

import tkinter as tk

TITLE_FONT = ("Helvetica", 18, "bold")

class SampleApp(tk.Tk):

    def __init__(self, *args, **kwargs):
        tk.Tk.__init__(self, *args, **kwargs)

        # the container is where we'll stack a bunch of frames
        # on top of each other, then the one we want visible
        # will be raised above the others
        container = tk.Frame(self)
        container.pack(side="top", fill="both", expand=True)
        container.grid_rowconfigure(0, weight=1)
        container.grid_columnconfigure(0, weight=1)

        self.frames = {}
        for F in (StartPage, PageOne, PageTwo):
            frame = F(container, self)
            self.frames[F] = frame
            # put all of the pages in the same location;
            # the one on the top of the stacking order
            # will be the one that is visible.
            frame.grid(row=0, column=0, sticky="nsew")

        self.show_frame(StartPage)

    def show_frame(self, c):
        '''Show a frame for the given class'''
        frame = self.frames[c]
        frame.tkraise()


class StartPage(tk.Frame):

    def __init__(self, parent, controller):

        tk.Frame.__init__(self, parent)
        label = tk.Label(self, text="CALCULO DE PRECIOS", font=TITLE_FONT)
        label.pack(side="top", fill="x", pady=10)

        test1 = tk.Spinbox(self, values=(1, 2, 4, 8))
        test1.pack()

        test2 = tk.Spinbox(self, values=(1, 2, 4, 8))
        test2.pack()

        button1 = tk.Button(self, width=20, text="Calculo Final",
                            command=lambda: controller.show_frame(PageOne))
        button2 = tk.Button(self, width=20, text="Calculo Actividades",
                            command=lambda: controller.show_frame(PageTwo))
        button1.pack()
        button2.pack()

class PageOne(tk.Frame):

    def __init__(self, parent, controller):
        tk.Frame.__init__(self, parent)
        label = tk.Label(self, text="CALCULO FINAL", font=TITLE_FONT)
        label.pack(side="top", fill="x", pady=10)
        button = tk.Button(self, width=20, text="Volver al menu principal",
                           command=lambda: controller.show_frame(StartPage))
        button.pack()




class PageTwo(tk.Frame):

    def __init__(self, parent, controller):
        tk.Frame.__init__(self, parent)
        label = tk.Label(self, text="CALCULO ACTIVIDADES", font=TITLE_FONT)
        label.pack(side="top", fill="x", pady=10)
        button = tk.Button(self, width=20, text="Volver al menu principal",
                           command=lambda: controller.show_frame(StartPage))
        button.pack()


if __name__ == "__main__":
    app = SampleApp()
    app.mainloop()

Answer 1

由于您创建的每个窗口都是具有对控制器的引用的类的实例，因此可以通过在控制器上设置值来在窗口之间传递变量。

例如，在从PageOne 创建的窗口中，您可以像这样在控制器上设置一个值： 在init 中，确保在PageOne 和PageTwo 两个类中存储对控制器的引用：

self.controller = controller

当你想要传递一个变量时，你可以在控制器对象上设置它：

self.controller.value = "value"

在从PageTwo 创建的窗口中，您可以像这样访问这个值：

value_from_other_window = self.controller.value

要回答您的其他问题，要从 spinbox 访问值，您需要有 spinbox 对象的引用。我建议您将这些保留为 PageOne 和 PageTwo 类的实例变量：

self.test1 = tk.Spinbox(self, values=(1, 2, 4, 8))

当需要访问值时，可以调用：

self.test1.get()

您可能不应该有两个类PageOne 和PageTwo，因为它们中的每一个似乎都有完全相同的代码，但对于标签文本。您可以考虑在 init 中添加另一个参数，即标签文本。

Answer 2

我已修改您的代码，以使用旋转框小部件的特性检索 StartPage 类中旋转框的选定值，并在按钮回调中打印 PageOne 和 PageTwo 类中的当前值：

import tkinter as tk
TITLE_FONT = ("Helvetica", 18, "bold")
class SampleApp(tk.Tk):
    def __init__(self, *args, **kwargs):
        tk.Tk.__init__(self, *args, **kwargs)
        container = tk.Frame(self)
        container.pack(side="top", fill="both", expand=True)
        container.grid_rowconfigure(0, weight=1)
        container.grid_columnconfigure(0, weight=1)
        self.varSpin1=1
        self.varSpin2=1

        self.frames = {}
        for F in (StartPage, PageOne, PageTwo):
            frame = F(container, self)
            self.frames[F] = frame
            frame.grid(row=0, column=0, sticky="nsew")
        self.show_frame(StartPage)

    def show_frame(self, c):
        '''Show a frame for the given class'''
        frame = self.frames[c]
        frame.tkraise()
        #print("spinbox values: %d %d"%(self.varSpin1,self.varSpin2))

class StartPage(tk.Frame):
    def setVarSpin1(self,v):
        self.controller.varSpin1=v
    def setVarSpin2(self,v):
        self.controller.varSpin2=v
    def __init__(self, parent, controller):
        tk.Frame.__init__(self, parent)
        label = tk.Label(self, text="CALCULO DE PRECIOS", font=TITLE_FONT)
        label.pack(side="top", fill="x", pady=10)
        self.controller=controller
        val1 = tk.IntVar()
        val2 = tk.IntVar()
        self.test1 = tk.Spinbox(self, values=(1,2,4,8), textvariable=val1,
                                command=lambda:self.setVarSpin1(val1.get())).pack()
        self.test2 = tk.Spinbox(self, values=(1,2,4,8), textvariable=val2,
                                command=lambda:self.setVarSpin2(val2.get())).pack()
        button1 = tk.Button(self, width=20, text="Calculo Final",
                            command=lambda: controller.show_frame(PageOne)).pack()
        button2 = tk.Button(self, width=20, text="Calculo Actividades",
                            command=lambda: controller.show_frame(PageTwo)).pack()

class PageOne(tk.Frame):
    def callback(self):
        print("PageOne: spinbox values: %d %d"%(self.controller.varSpin1,self.controller.varSpin2))
        self.controller.show_frame(StartPage)
    def __init__(self, parent, controller):
        tk.Frame.__init__(self, parent)
        label = tk.Label(self, text="CALCULO FINAL", font=TITLE_FONT)
        label.pack(side="top", fill="x", pady=10)
        button = tk.Button(self, width=20, text="Volver al menu principal",
                           command=lambda:self.callback()).pack()
        self.controller=controller        

class PageTwo(tk.Frame):
    def callback(self):
        print("PageTwo: spinbox values: %d %d"%(self.controller.varSpin1,self.controller.varSpin2))
        self.controller.show_frame(StartPage)   
    def __init__(self, parent, controller):
        tk.Frame.__init__(self, parent)
        label = tk.Label(self, text="CALCULO ACTIVIDADES", font=TITLE_FONT)
        label.pack(side="top", fill="x", pady=10)
        button = tk.Button(self, width=20, text="Volver al menu principal",
                           command=lambda:self.callback()).pack()
        self.controller=controller

if __name__ == "__main__":
    app = SampleApp()
    app.mainloop()