Tkinter实现选中两个Checkbutton绘制连线及颜色切换方案咨询

Got it, let's fix this up for you. I've modified your original code to add the line-drawing feature, along with the ability to toggle line color by clicking the first selected checkbox. Here's the complete working code:

from tkinter import *

root = Tk()
root.title("Checkbutton Connector")

# Store checkbutton data: [IntVar, position, widget, x, y]
buttons = []
# Store line data: [button1, button2, line_id]
lines = []
# Track selected buttons for drawing lines
selected_buttons = []

class CMD:
    """Auxiliary class for callback functions with parameters"""
    def __init__(self, func, *args):
        self.func = func
        self.args = args
    def __call__(self, *args):
        combined_args = self.args + args
        self.func(*combined_args)

def toggle_checkbutton_color(pos=0):
    """Toggle checkbutton background color based on its state"""
    if buttons[pos][0].get() == 1:
        buttons[pos][2].configure(bg='red')
    else:
        buttons[pos][2].configure(bg='green')

def handle_checkbutton_click(pos=0):
    """Handle checkbutton click: toggle color + manage line selection/drawing"""
    toggle_checkbutton_color(pos)
    
    # Only proceed if line-drawing mode is active
    if line.get() != 1:
        return
    
    clicked_btn = buttons[pos]
    
    # Check if this is the first selected button
    if not selected_buttons:
        selected_buttons.append(clicked_btn)
        # Highlight the selected button temporarily
        clicked_btn[2].configure(bg='orange')
    else:
        # Check if we're clicking the first selected button (to toggle line color)
        if clicked_btn == selected_buttons[0]:
            # Find the line connected to this button
            for line_data in lines:
                if line_data[0] == clicked_btn:
                    current_color = canvas.itemcget(line_data[2], 'fill')
                    new_color = 'blue' if current_color == 'black' else 'black'
                    canvas.itemconfig(line_data[2], fill=new_color)
            # Reset selection and revert highlight
            selected_buttons[0][2].configure(bg='red' if selected_buttons[0][0].get() ==1 else 'green')
            selected_buttons.clear()
        else:
            # Second button selected: draw line between them
            btn1 = selected_buttons[0]
            btn2 = clicked_btn
            
            # Calculate center coordinates of both buttons
            btn1_center_x = btn1[3] + btn1[2].winfo_width()//2
            btn1_center_y = btn1[4] + btn1[2].winfo_height()//2
            btn2_center_x = btn2[3] + btn2[2].winfo_width()//2
            btn2_center_y = btn2[4] + btn2[2].winfo_height()//2
            
            # Draw the line on canvas
            line_id = canvas.create_line(btn1_center_x, btn1_center_y, btn2_center_x, btn2_center_y, fill='black', width=2)
            lines.append([btn1, btn2, line_id])
            
            # Reset selection and revert highlight
            selected_buttons[0][2].configure(bg='red' if btn1[0].get() ==1 else 'green')
            selected_buttons.clear()

def place_checkbutton_in_canvas(e):
    """Place a new checkbutton on canvas when clicking empty area"""
    # Only place if we're not clicking an existing checkbutton
    if str(e.widget) == str(canvas):
        b = IntVar()
        pos = len(buttons)
        x = e.x
        y = e.y
        
        # Create checkbutton on canvas
        btn = Checkbutton(canvas, variable=b, command=CMD(handle_checkbutton_click, pos))
        btn.place(x=x, y=y)
        # Store button data including position
        buttons.append([b, pos, btn, x, y])
        toggle_checkbutton_color(pos)

# Create canvas to hold checkbuttons and lines
canvas = Canvas(root, width=800, height=600, bg='white')
canvas.pack(fill=BOTH, expand=True)

# Line-drawing mode toggle
line = IntVar()
draw_line_check = Checkbutton(root, text="Enable Line Drawing", variable=line)
draw_line_check.pack(side=TOP, anchor=W, padx=5, pady=5)

# Bind canvas click to add checkbuttons
canvas.bind('<Button-1>', place_checkbutton_in_canvas)

root.mainloop()

Key Changes & Explanations: #

• Switched to Canvas Container: I replaced direct placement on root with a Canvas widget. This lets us draw lines directly on the same surface as the checkbuttons, which is far more manageable for interactive drawing.
• Enhanced Button Tracking: Each checkbutton now stores its x/y position along with its widget and state variable, so we can calculate center points for drawing lines.
• Combined Click Handler: The handle_checkbutton_click function now does two things: toggles the button's color and manages the line-selection workflow when line-drawing mode is active.
• Line Drawing Logic:
  • When line mode is on, clicking the first checkbutton highlights it temporarily (orange)
  • Clicking a second checkbutton draws a black line between their centers
  • Clicking the first selected button again toggles the line's color between black and blue
• Line State Storage: The lines list keeps track of all drawn lines and their associated buttons, so we can find and modify lines later when toggling colors.

内容的提问来源于stack exchange，提问作者fernando