在tkinter菜单中切换帧

Question

I've used Tkinter to create a GUI with different menu options (a similar example is produced below). Each menu has different commands, which when clicked create a new frame. Now what is happening is if I switch to a different command, the new frame stacks below the current frame instead of replacing the old one.

I want to know what is the best way to move forward.

import Tkinter as tkinter
root = tkinter.Tk()
root.minsize(400,300)
welcome = tkinter.Frame(root).grid()
label = tkinter.Label(welcome, text="Welcome to my program").grid(row=0, column=3)
button = tkinter.Button(welcome,text="Exit",command=root.destroy).grid(row=3, column=1)
def newFrame():
newFrame = tkinter.Frame(root).grid()
newFrame_name = tkinter.Label(newFrame, text="This is another frame").grid()
menu = tkinter.Menu(root)
root.config(menu=menu)
main_menu = tkinter.Menu(menu)
menu.add_cascade(label="Main Menu", menu= main_menu)
main_menu.add_command(label="New Frame", command=newFrame)
main_menu.add_command(label="Another Frame", command=newFrame)
#menu.add_command(label="Exit", command=root.destroy, menu= filemenu)
root.mainloop()

Now if I switch between New Frame and Another Frame, the windows stack up, but I want one window to replace the other.

Any ideas? Thanks.

Answer 1

Here is a minimal example of one method I used recently; the key is in PythonGUI.show_frame , which moves the appropriate frame to the front for display.

import Tkinter as tk

class BaseFrame(tk.Frame):
    """An abstract base class for the frames that sit inside PythonGUI.

    Args:
      master (tk.Frame): The parent widget.
      controller (PythonGUI): The controlling Tk object.

    Attributes:
      controller (PythonGUI): The controlling Tk object.

    """

    def __init__(self, master, controller):
        tk.Frame.__init__(self, master)
        self.controller = controller
        self.grid()
        self.create_widgets()

    def create_widgets(self):
        """Create the widgets for the frame."""
        raise NotImplementedError


class ExecuteFrame(BaseFrame):
    """The application home page.

    Attributes:
      new_button (tk.Button): The button to switch to HomeFrame.

    """

    def create_widgets(self):
        """Create the base widgets for the frame."""
        self.new_button = tk.Button(self,
                                    anchor=tk.W,
                                    command=lambda: self.controller.show_frame(HomeFrame),
                                    padx=5,
                                    pady=5,
                                    text="Home")
        self.new_button.grid(padx=5, pady=5, sticky=tk.W+tk.E)


class HomeFrame(BaseFrame):
    """The application home page.

    Attributes:
      new_button (tk.Button): The button to switch to ExecuteFrame.

    """

    def create_widgets(self):
        """Create the base widgets for the frame."""
        self.new_button = tk.Button(self,
                                    anchor=tk.W,
                                    command=lambda: self.controller.show_frame(ExecuteFrame),
                                    padx=5,
                                    pady=5,
                                    text="Execute")
        self.new_button.grid(padx=5, pady=5, sticky=tk.W+tk.E)


class PythonGUI(tk.Tk):
    """The main window of the GUI.

    Attributes:
      container (tk.Frame): The frame container for the sub-frames.
      frames (dict of tk.Frame): The available sub-frames.

    """

    def __init__(self):
        tk.Tk.__init__(self)
        self.title("Python GUI")
        self.create_widgets()
        self.resizable(0, 0)

    def create_widgets(self):
        """Create the widgets for the frame."""             
        #   Frame Container
        self.container = tk.Frame(self)
        self.container.grid(row=0, column=0, sticky=tk.W+tk.E)

        #   Frames
        self.frames = {}
        for f in (HomeFrame, ExecuteFrame): # defined subclasses of BaseFrame
            frame = f(self.container, self)
            frame.grid(row=2, column=2, sticky=tk.NW+tk.SE)
            self.frames[f] = frame
        self.show_frame(HomeFrame)

    def show_frame(self, cls):
        """Show the specified frame.

        Args:
          cls (tk.Frame): The class of the frame to show. 

        """
        self.frames[cls].tkraise()

if __name__ == "__main__":
    app = PythonGUI()
    app.mainloop()
    exit()

Answer 2

There are two basic ways to solve the problem:

1. stack all of the frames on top of each other (eg: put in the same grid cell, or use place with the same options) and then raise the one that should be visible to the top of the stack (using frame.lift() ). An example of the technique is in this answer: Switch between two frames in tkinter

2. Whenever you show a new frame, destroy (with .destroy() or hide (with pack_forget or grid_forget ) the old frame.

Answer 3

I have a simple example. I'm sorry, because I don't know how to do this code by class . I just using simple code. But it's works! :D Here it is:

from Tkinter import *
def gantihal(frame):
    frame.tkraise()

root = Tk()

f1 = Frame(root)
f2 = Frame(root)
f3 = Frame(root)
f4 = Frame(root)
for frame in (f1, f2, f3, f4):
    frame.grid(row=0, column=0, sticky='news')

Button(f1, text='goto frame 2', command=lambda:gantihal(f2)).pack()
Label(f1, text='this is in frame 1').pack()

Label(f2, text='this is in frame two').pack()
Button(f2, text='goto frame 3', command=lambda:gantihal(f3)).pack()

Label(f3, text='this is in frame 3').pack(side='left')
Button(f3, text='next frame :)', command=lambda:gantihal(f4)).pack(side='left')

Label(f4, text='fourth frame').pack()
Button(f4, text='goto 1st frame', command=lambda:gantihal(f1)).pack()

gantihal(f1)
root.mainloop()