Python Tkinter 将键盘键绑定到画布上的元素项目

我已经知道您可以将键绑定到小部件，或者将鼠标单击绑定到画布上的元素(例如:矩形、线条等)，后者的示例如下:

import tkinter as tk


class App:
    def __init__(self, master):
        self.master = master
        self.canvas = tk.Canvas(master, width=400, height=400)
        self.canvas.pack()

        # Create the main rectangle
        self.rect = self.canvas.create_rectangle(100, 100, 300, 300, fill="white", outline="black")

        # Create the three small rectangles inside the main rectangle
        self.rect1 = self.canvas.create_rectangle(120, 120, 180, 180, fill="white", outline="black", tags="button1")
        self.rect2 = self.canvas.create_rectangle(220, 120, 280, 180, fill="white", outline="black", tags="button2")
        self.rect3 = self.canvas.create_rectangle(170, 220, 230, 280, fill="white", outline="black", tags="button3")

        # Bind the buttons to the click event and call the hover function
        self.canvas.tag_bind("button1", "<Button-1>", lambda event, tag="button1": self.button_click(event, tag))
        self.canvas.tag_bind("button2", "<Button-1>", lambda event, tag="button2": self.button_click(event, tag))
        self.canvas.tag_bind("button3", "<Button-1>", lambda event, tag="button3": self.button_click(event, tag))

        self.canvas.tag_bind("button1", "<Enter>", lambda event, tag="button1": self.hover(event, tag))
        self.canvas.tag_bind("button2", "<Enter>", lambda event, tag="button2": self.hover(event, tag))
        self.canvas.tag_bind("button3", "<Enter>", lambda event, tag="button3": self.hover(event, tag))

        self.canvas.tag_bind("button1", "<Leave>", lambda event, tag="button1": self.leave(event, tag))
        self.canvas.tag_bind("button2", "<Leave>", lambda event, tag="button2": self.leave(event, tag))
        self.canvas.tag_bind("button3", "<Leave>", lambda event, tag="button3": self.leave(event, tag))

    def button_click(self, event, tag):
        # Get the coordinates of the clicked rectangle
        x1, y1, x2, y2 = self.canvas.coords(tag)

        # Create a grey rectangle around the clicked rectangle
        self.canvas.delete("clicked")
        self.canvas.create_rectangle(x1 - 5, y1 - 5, x2 + 5, y2 + 5, outline="grey", fill="grey", tags="clicked")

    def hover(self, event, tag):
        # Get the coordinates of the hovered rectangle
        x1, y1, x2, y2 = self.canvas.coords(tag)

        # Create a grey rectangle around the hovered rectangle
        self.canvas.create_rectangle(x1 - 5, y1 - 5, x2 + 5, y2 + 5, outline="grey", tags="hover")

    def leave(self, event, tag):
        # Remove the grey rectangle when the mouse leaves the rectangle
        self.canvas.delete("hover")


root = tk.Tk()
app = App(root)
root.mainloop()

上面的方法适用于将鼠标点击绑定到一个矩形.但后来我注意到，如果我用<KeyPress>或<Key>或特定的键替换<Button-1>，例如<BackSpace>，它实际上并不起作用.

我一开始以为这是因为没有对准焦点而不起作用，所以我试着使用canvas.focus_set()，但只有当我使用<Enter>或<Leave>时才有效，而使用canvas.tag_bind:

import tkinter as tk

root = tk.Tk()
canvas = tk.Canvas(root, width=200, height=200)
canvas.pack()

canvas.create_line(10, 10, 100, 100, tags="mytag")

canvas.create_line(10, 20, 100, 80, tags="mytag")

canvas.create_oval(50, 50, 60, 60, fill="black", tags="mytag")

canvas.create_oval(50, 80, 70, 90, fill="blue", tags="no")



canvas.tag_bind("mytag", "<Enter>", lambda event: print("entered element with mytag"))
canvas.tag_bind("mytag", "<Leave>", lambda event: print("leaving element with mytag"))

root.mainloop()

将鼠标悬停在元素上，除了蓝点，似乎是有效的.我发现对绑定键有效的唯一方法是在使用上面的bind_all键时:

def on_keypress(event):
    element_ids = canvas.find_withtag("current")
    if element_ids:
        print("Key pressed over element:", element_ids)

canvas.tag_bind("mytag", "<Enter>", lambda event: canvas.focus_set())
canvas.tag_bind("mytag", "<Leave>", lambda event: root.focus_set())
canvas.bind_all("<KeyPress>", on_keypress)

编辑:看起来用canvas.bind代替canvas.bind_all也行.

但这并不理想，因为我想将单个键绑定到单个"组"元素(例如:它们都共享相同的标签).

除了我自己的非工作try 之外，还有什么方法可以做到这一点吗？