Python：带有画布的 Tkinter 中的滚动条

Question

我使用 Canvas 为我的 tkinter 应用程序使用了滚动条。我正在使用 Pack 来设置滚动条。但我有一个问题。水平滚动条工作正常，但垂直滚动条不行。位置配置错误。

我的代码：

    self.scroll_x = tk.Scrollbar(self, orient=tk.HORIZONTAL)
    self.scroll_y = tk.Scrollbar(self, orient=tk.VERTICAL)
    self.canvas = tk.Canvas(self, width=600, height=100,
    xscrollcommand=self.scroll_x.set,
    yscrollcommand=self.scroll_y.set)
    self.scroll_x.config(command=self.canvas.xview)
    self.scroll_y.config(command=self.canvas.yview)
    self.frame = tk.Frame(self.canvas)

     self.canvas.create_window((0, 0), window=self.frame,anchor=tk.NW)
     self.canvas.bind_all("<MouseWheel>", self.on_mousewheel)
     self.canvas.config(scrollregion=self.canvas.bbox(tk.ALL))
     self.canvas.pack(side=tk.LEFT,expand=True,fill=tk.BOTH)
     self.scroll_x.pack(side=tk.BOTTOM,fill=tk.X)
     self.scroll_y.pack(side=tk.RIGHT,fill=tk.Y)
     self.bind("<Configure>", self.resize)
            
     self.update_idletasks()

def on_mousewheel(self, event):
    shift = (event.state & 0x1) != 0
    scroll = -1 if event.delta > 0 else 1
    if shift:
        self.canvas.xview_scroll(scroll, "units")
    else:
        self.canvas.yview_scroll(scroll, "units")

def resize(self, event):
    region = self.canvas.bbox(tk.ALL)
    self.canvas.configure(scrollregion=region)

Answer 1

我建议在这种情况下使用网格。 See more

import tkinter as tk

class MyFigure(tk.Frame):
    def __init__(self, master):
        tk.Frame.__init__(self, master)
        
        self.scroll_x = tk.Scrollbar(self, orient=tk.HORIZONTAL)
        self.scroll_y = tk.Scrollbar(self, orient=tk.VERTICAL)
        self.canvas = tk.Canvas(self, width=600, height=100, bg='red',
                                xscrollcommand=self.scroll_x.set,
                                yscrollcommand=self.scroll_y.set)
        self.scroll_x.config(command=self.canvas.xview)
        self.scroll_y.config(command=self.canvas.yview)
        self.frame = tk.Frame(self.canvas)
        self.canvas.create_window((0, 0), window=self.frame,anchor=tk.NW)
        self.canvas.bind_all("<MouseWheel>", self.on_mousewheel)
        self.canvas.config(scrollregion=self.canvas.bbox(tk.ALL))
        
        self.canvas.grid(column=0,row=0)
        self.scroll_x.grid(column=0,row=1,sticky='ew')
        self.scroll_y.grid(column=1,row=0,sticky='ns')
        self.bind("<Configure>", self.resize)

    def on_mousewheel(self, event):
        shift = (event.state & 0x1) != 0
        scroll = -1 if event.delta > 0 else 1
        if shift:
            self.canvas.xview_scroll(scroll, "units")
        else:
            self.canvas.yview_scroll(scroll, "units")

    def resize(self, event):
        region = self.canvas.bbox(tk.ALL)
        self.canvas.configure(scrollregion=region)

root = tk.Tk()
mf = MyFigure(root)
mf.pack()
root.mainloop()

如果您真的需要使用 pack，请注意，以复杂的方式使用它，打包小部件的顺序很重要。我认为使用网格订购框架的其余部分更容易，而不是尝试将它们打包在一起。

不管怎样，替换上面代码中的这些行就可以了：

self.scroll_x.pack(side=tk.BOTTOM,fill=tk.X)
self.canvas.pack(side=tk.LEFT,expand=True,fill=tk.BOTH)
self.scroll_y.pack(side=tk.LEFT,fill=tk.Y)