Got it, let's figure out why only the last page's scrollbar works—this is a classic Tkinter event binding pitfall! The root cause is your use of bind_all for the mouse wheel events: every time you create a new page, you're overwriting the global application-wide binding with the current page's scroll handler. That's why only the last page's scroll logic gets triggered no matter which page you're on.

Here's the Fix #

We'll address this in two key ways:

1. Replace bind_all with widget-specific bind: This ensures each page's scroll events only trigger its own handler.
2. Create a reusable scrollable frame base class: Cut down on duplicate code and make your pages cleaner.

Modified Code Implementation #

First, let's build a base ScrollableFrame class that encapsulates all the scrollbar logic—this way you don't repeat the same code in every page:

from Tkinter import *

def quit():
    master.destroy()

class ScrollableFrame(Frame):
    def __init__(self, *args, **kwargs):
        Frame.__init__(self, *args, **kwargs)
        
        # Set up scrollbars and canvas
        self.canvas = Canvas(self, background="#ffffff", highlightcolor="white", takefocus=True)
        self.canvas.pack(side="left", fill="both", anchor="center", expand=True)
        
        self.vscrollbar = Scrollbar(self, orient="vertical", command=self.canvas.yview)
        self.vscrollbar.pack(side="right", fill="y")
        self.canvas.configure(yscrollcommand=self.vscrollbar.set)
        
        self.hscrollbar = Scrollbar(self, orient="horizontal", command=self.canvas.xview)
        self.hscrollbar.pack(side="bottom", fill="x")
        self.canvas.configure(xscrollcommand=self.hscrollbar.set)
        
        self.container = Frame(self.canvas, highlightcolor="white")
        self.canvas.create_window(0, 0, window=self.container, anchor="center")
        
        # Bind events to THIS frame's canvas (not global)
        self.container.bind("<Configure>", self.onFrameConfigure)
        self.canvas.bind("<MouseWheel>", self.on_vertical)
        self.canvas.bind("<Shift-MouseWheel>", self.on_horizontal)
        
        # Optional: Make sure canvas gets focus when the frame is raised
        self.bind("<Map>", lambda e: self.canvas.focus_set())

    def onFrameConfigure(self, event):
        self.canvas.configure(scrollregion=self.canvas.bbox("all"))

    def on_vertical(self, event):
        self.canvas.yview_scroll(-1 * event.delta, 'units')

    def on_horizontal(self, event):
        self.canvas.xview_scroll(-1 * event.delta, 'units')

Now inherit this base class for each of your pages—this keeps your page code clean and avoids repetition:

class FirstPage(ScrollableFrame):
    def __init__(self, *args, **kwargs):
        ScrollableFrame.__init__(self, *args, **kwargs)
        # Add your page-specific widgets to self.container
        self.label = Label(self.container, text="Welcome! This is Page 1 with lots of content to scroll.")
        self.label.pack(side="top", fill="both", expand=False)
        
        # Add some tall content to test scrolling
        for i in range(50):
            Label(self.container, text=f"Line {i+1} of Page 1").pack()

class SecondPage(ScrollableFrame):
    def __init__(self, *args, **kwargs):
        ScrollableFrame.__init__(self, *args, **kwargs)
        self.label = Label(self.container, text="Hello World! This is Page 2 with horizontal scroll.")
        self.label.pack(side="top", fill="both", expand=False)
        
        # Wide content for horizontal scroll test
        wide_label = Label(self.container, text=" " * 200 + "Wide content to test horizontal scrolling" + " " * 200)
        wide_label.pack()

class ThirdPage(ScrollableFrame):
    def __init__(self, *args, **kwargs):
        ScrollableFrame.__init__(self, *args, **kwargs)
        self.label = Label(self.container, text="This is Page 3, fully scrollable too!")
        self.label.pack(side="top", fill="both", expand=False)
        
        # Mixed content for testing both scroll directions
        for i in range(30):
            Label(self.container, text=f"Line {i+1} | " + "Long text " * 50).pack()

Finally, add the main window logic to handle page navigation (you had this part missing in your snippet):

class MainApp(Tk):
    def __init__(self, *args, **kwargs):
        Tk.__init__(self, *args, **kwargs)
        
        # Container frame to hold all pages
        container = Frame(self)
        container.pack(side="top", fill="both", expand=True)
        
        self.frames = {}
        # Add all pages to the frames dictionary
        for F in (FirstPage, SecondPage, ThirdPage):
            frame = F(container)
            self.frames[F] = frame
            frame.grid(row=0, column=0, sticky="nsew")
        
        # Navigation buttons
        nav_frame = Frame(self)
        nav_frame.pack(side="bottom", fill="x")
        
        Button(nav_frame, text="Page 1", command=lambda: self.show_frame(FirstPage)).pack(side="left")
        Button(nav_frame, text="Page 2", command=lambda: self.show_frame(SecondPage)).pack(side="left")
        Button(nav_frame, text="Page 3", command=lambda: self.show_frame(ThirdPage)).pack(side="left")
        Button(nav_frame, text="Quit", command=quit).pack(side="right")
        
        # Show the first page initially
        self.show_frame(FirstPage)
    
    def show_frame(self, cont):
        frame = self.frames[cont]
        frame.tkraise()
        # Ensure the canvas gets focus so scroll events work immediately
        frame.canvas.focus_set()

if __name__ == "__main__":
    master = MainApp()
    master.geometry("800x600")
    master.mainloop()

Key Changes Explained #

• Widget-specific binding: Using self.canvas.bind(...) instead of bind_all means each page's scroll events are tied only to its own canvas. No more overwriting global bindings!
• Reusable base class: ScrollableFrame handles all the scrollbar setup, so you don't copy-paste code across pages.
• Focus management: The <Map> binding and focus_set() in show_frame ensure the canvas gets focus when the page is raised, so mouse wheel events work right away without clicking first.

Test this code out—each page should now scroll independently without interfering with each other!

内容的提问来源于stack exchange，提问作者Toria E.