I'm new to python . i'm trying to create login page . i need to change the frame after clicking login button . this is the error

Exception in Tkinter callback Traceback (most recent call last): File "C:\Users\Rashith Senishka\AppData\Local\Programs\Python\Python39\lib\tkinter_init_.py", line 1892, in call return self.func(*args) File "D:\Python\tkinter\Test_2\Proxlight_Designer_Export\main.py", line 57, in self.login_button = tk.Button(self, command=lambda: master.show_frame()) AttributeError: 'Frame' object has no attribute 'show_frame'

please help me to fix this error

 import tkinter as tk


class SchoolManegmentSystem(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.frames = {}
        for F in (LoginPageWidget, LoginPageWidget_W):
            frame = F(container)
            self.frames[F] = frame
            frame.grid(row=0, column=0, sticky="nsew")

        self.show_frame(LoginPageWidget)

    def show_frame(self, cont):
        frame = self.frames[cont]
        frame.tkraise()


class LoginPageWidget(tk.Frame):
    def __init__(self, master=None, **kw):
        super(LoginPageWidget, self).__init__(master, **kw)
        self.backg = tk.Label(self)
        self.img_background = tk.PhotoImage(file='background.png')
        background_color = "#1f1f1f"
        self.backg.configure(background=background_color, cursor='arrow', font='TkDefaultFont',
                             image=self.img_background)
        self.backg.configure(relief='flat')
        self.backg.place(anchor='nw', x='0', y='0')
        self.loginlabel = tk.Label(self)
        self.loginlabel.configure(anchor='n', background='#e7f4f9', compound='top', font='{Poppins} 23 {}')
        self.loginlabel.configure(foreground='#4f545c', justify='center', relief='flat', text='LOGIN')
        self.loginlabel.place(anchor='nw', x='460', y='70')
        self.usernamelabel = tk.Label(self)
        self.usernamelabel.configure(background='#e7f4f9', font='{Poppins} 12 {}', foreground='#828282', relief='flat')
        self.usernamelabel.configure(text='USERNAME')
        self.usernamelabel.place(anchor='nw', x='380', y='160')
        self.input_field_bg = tk.Label(self)
        self.img_img_textBox0 = tk.PhotoImage(file='img_textBox0.png')
        self.input_field_bg.configure(background='#e7f4f9', image=self.img_img_textBox0, relief='flat')
        self.input_field_bg.place(anchor='nw', x='365', y='185')
        self.password_label = tk.Label(self)
        self.password_label.configure(background='#e7f4f9', font='{Poppins} 12 {}', foreground='#828282', relief='flat')
        self.password_label.configure(text='PASSWORD')
        self.password_label.place(anchor='nw', x='380', y='240')
        self.input_field_bg_2 = tk.Label(self)
        self.input_field_bg_2.configure(background='#e7f4f9', image=self.img_img_textBox0, relief='flat')
        self.input_field_bg_2.place(anchor='nw', x='365', y='265')
        self.login_button = tk.Button(self, command=lambda: master.show_frame())
        self.img_img0 = tk.PhotoImage(file='img0.png')
        self.login_button.configure(activebackground='#e7f4f9', activeforeground='#e7f4f9', background='#e7f4f9',
                                    borderwidth='0')
        self.login_button.configure(cursor='hand2', disabledforeground='#e7f4f9', foreground='#e7f4f9',
                                    highlightbackground='#e7f4f9')
        self.login_button.configure(highlightcolor='#e7f4f9', image=self.img_img0, relief='flat')
        self.login_button.place(anchor='nw', x='400', y='350')
        self.username_input_field = tk.Entry(self)
        self.username_input_field.configure(background='#C7E4E0', font='{Poppins} 12 {}', insertbackground='#e7f4f9',
                                            insertborderwidth='3')
        self.username_input_field.configure(insertwidth='2', relief='flat', show='•')
        self.username_input_field.place(anchor='nw', height='40', x='380', y='269')
        self.password_input_field = tk.Entry(self)
        self.password_input_field.configure(background='#C7E4E0', font='{Poppins} 12 {}', insertbackground='#e7f4f9',
                                            insertborderwidth='3')
        self.password_input_field.configure(insertwidth='2', relief='flat')
        self.password_input_field.place(anchor='nw', height='40', x='380', y='190')
        self.button1 = tk.Button(self)
        self.button1.configure(relief='flat', text='CLEAR')
        self.button1.place(anchor='nw', x='0', y='0')
        self.configure(borderwidth='0', height='515', relief='flat', width='791')
        self.place(anchor='nw', x='0', y='0')


class LoginPageWidget_W(tk.Frame):
    def __init__(self, master=None, **kw):
        super(LoginPageWidget_W, self).__init__(master, **kw)
        self.backg = tk.Label(self)
        self.img_background = tk.PhotoImage(file='background.png')
        background_color = "#ffffff"
        self.backg.configure(background=background_color, cursor='arrow', font='TkDefaultFont',
                             image=self.img_background)
        self.backg.configure(relief='flat')
        self.backg.place(anchor='nw', x='0', y='0')
        self.loginlabel = tk.Label(self)
        self.loginlabel.configure(anchor='n', background='#e7f4f9', compound='top', font='{Poppins} 23 {}')
        self.loginlabel.configure(foreground='#4f545c', justify='center', relief='flat', text='LOGIN')
        self.loginlabel.place(anchor='nw', x='460', y='70')
        self.usernamelabel = tk.Label(self)
        self.usernamelabel.configure(background='#e7f4f9', font='{Poppins} 12 {}', foreground='#828282', relief='flat')
        self.usernamelabel.configure(text='USERNAME')
        self.usernamelabel.place(anchor='nw', x='380', y='160')
        self.input_field_bg = tk.Label(self)
        self.img_img_textBox0 = tk.PhotoImage(file='img_textBox0.png')
        self.input_field_bg.configure(background='#e7f4f9', image=self.img_img_textBox0, relief='flat')
        self.input_field_bg.place(anchor='nw', x='365', y='185')
        self.password_label = tk.Label(self)
        self.password_label.configure(background='#e7f4f9', font='{Poppins} 12 {}', foreground='#828282', relief='flat')
        self.password_label.configure(text='PASSWORD')
        self.password_label.place(anchor='nw', x='380', y='240')
        self.input_field_bg_2 = tk.Label(self)
        self.input_field_bg_2.configure(background='#e7f4f9', image=self.img_img_textBox0, relief='flat')
        self.input_field_bg_2.place(anchor='nw', x='365', y='265')
        self.login_button = tk.Button(self)
        self.img_img0 = tk.PhotoImage(file='img0.png')
        self.login_button.configure(activebackground='#e7f4f9', activeforeground='#e7f4f9', background='#e7f4f9',
                                    borderwidth='0')
        self.login_button.configure(cursor='hand2', disabledforeground='#e7f4f9', foreground='#e7f4f9',
                                    highlightbackground='#e7f4f9')
        self.login_button.configure(highlightcolor='#e7f4f9', image=self.img_img0, relief='flat', command=self.quit)
        self.login_button.place(anchor='nw', x='400', y='350')
        self.username_input_field = tk.Entry(self)
        self.username_input_field.configure(background='#C7E4E0', font='{Poppins} 12 {}', insertbackground='#e7f4f9',
                                            insertborderwidth='3')
        self.username_input_field.configure(insertwidth='2', relief='flat', show='•')
        self.username_input_field.place(anchor='nw', height='40', x='380', y='269')
        self.password_input_field = tk.Entry(self)
        self.password_input_field.configure(background='#C7E4E0', font='{Poppins} 12 {}', insertbackground='#e7f4f9',
                                            insertborderwidth='3')
        self.password_input_field.configure(insertwidth='2', relief='flat')
        self.password_input_field.place(anchor='nw', height='40', x='380', y='190')
        self.button1 = tk.Button(self)
        self.button1.configure(relief='flat', text='CLEAR')
        self.button1.place(anchor='nw', x='0', y='0')
        self.configure(borderwidth='0', height='515', relief='flat', width='791')
        self.place(anchor='nw', x='0', y='0')




app = SchoolManegmentSystem()
app.resizable(False, False)
app.eval('tk::PlaceWindow . center')
app.overrideredirect(True)
app.mainloop()

CodePudding user response：

master of LoginPageWidget is a frame (container) inside SchoolManegmentSystem. You need to pass instance of SchoolManegmentSystem to LoginPageWidget as well in order to call its show_frame():

class SchoolManegmentSystem(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.frames = {}
        for F in (LoginPageWidget, LoginPageWidget_W):
            frame = F(container, self) # pass itself to frame as well
            self.frames[F] = frame
            frame.grid(row=0, column=0, sticky="nsew")

        self.show_frame(LoginPageWidget)

    ...

class LoginPageWidget(tk.Frame):
    def __init__(self, master, controller, **kw): # added controller argument
        super(LoginPageWidget, self).__init__(master, **kw)
        self.controller = controller # save a reference for later use
        ...
        self.login_button = tk.Button(self, command=lambda: controller.show_frame(LoginPageWidget_W)) # use controller instead of master
        ...