使用 tkinter 根据 OptionMenu 回答更改复选框列表

Question

tkinter 有点麻烦

事情是这样的： 我有一个dropdown (OptionMenu)，可以让我选择一些东西。

我在来自OptionMenu 的变量上设置了一个tracer，它在下拉列表更改时调用一个函数。 （函数callback_project_name_changed）

当回调被调用时，我检查已选择的项目并显示我想要的相应复选框列表。

这是我目前的代码：

from tkinter import *
import os
import sys
from tkinter import filedialog


class Checkbar(Frame):
    def __init__(self, parent=None, picks=[], side=LEFT, anchor=W):
        Frame.__init__(self, parent)
        self.vars = []
        for pick in picks:
            var = IntVar()
            chk = Checkbutton(self, text=pick, variable=var)
            chk.pack(side=side, anchor=anchor, expand=YES)
            self.vars.append(var)

    def state(self):
        return map((lambda var: var.get()), self.vars)


class Application():
    def __init__(self):
        self.window = Tk()

    def close_window(self):
        self.window.destroy()
        sys.exit()

    def close_window_escape(self, event):
        self.window.destroy()
        sys.exit()

    def get_project_path(self):
        self.path = filedialog.askdirectory()
        print(self.path)

    def callback_project_name_changed(self, *args):
        # @todo: Make groups like when you tick `tests` it ticks all the tests
        self.project_selected = self.project.get()
        if self.project_selected == "other":
            # @todo: whitelist/blacklist for options
            self.options = Checkbar(self.window, ['author', 'norme', 'Makefile'])
            self.options.pack(side=LEFT)

        if self.project_selected == "42commandements":
            self.options = None

        if self.project_selected == "libft":
            self.options = Checkbar(self.window, ['author', 'forbidden-functions', 'makefile', 'norme', 'static', 'extra', 'required', 'bonus', 'benchmark', 'tests', 'libftest', 'maintest', 'moulitest', 'fillit-checker', 'libft-unit-test'])
            self.options.pack(side=LEFT)

        if self.project_selected == "fillit":
            self.options = Checkbar(self.window, ['author', 'forbidden-functions', 'makefile', 'norme', 'tests', 'fillit-checker'])
            self.options.pack(side=LEFT)

    def start(self):
        if self.options != None:
            print(list(self.options.state()))

    def create_window(self):
        self.window.title("42PyChecker")
        self.window.minsize(width=800, height=800)
        # @todo: Set a icon for app image
        #self.window.iconbitmap(os.path.dirname(os.path.realpath(__file__)) + "/favicon.ico")
        # @todo: Find a way to loop through gif frames to have animated logo
        logo = PhotoImage(file=os.path.dirname(os.path.realpath(__file__)) + "/logo.gif")
        Label(self.window, image=logo).pack()
        Button(self.window, text="Select Project Path", width=20, command=self.get_project_path).pack()

        self.project = StringVar(self.window)
        dropdown = OptionMenu(self.window, self.project, "other", "42commandements", "libft", 'fillit')
        dropdown.pack()

        Button(self.window, text="Start", command=self.start).pack(side=BOTTOM)

        Button(self.window, text="Exit", command=self.close_window).pack(side=BOTTOM)
        self.window.bind('<Escape>', self.close_window_escape)

        self.project.trace("w", self.callback_project_name_changed)
        self.window.mainloop()
app = Application()
app.create_window()

如果您运行它并多次更改下拉菜单（更改为相同或不同的选项），它只会添加更多复选框而不会删除任何复选框。 我想这应该会发生，因为我没有删除任何内容，只是在每次更改下拉菜单时添加 CheckBars。

现在让我们更改一些代码并尝试添加.destroy() 或.pack_forget()：

    def callback_project_name_changed(self, *args):
        # @todo: Make groups like when you tick `tests` it ticks all the tests
        self.project_selected = self.project.get()
        if self.project_selected == "other":
            self.options.destroy()
            # @todo: whitelist/blacklist for options
            self.options = Checkbar(self.window, ['author', 'norme', 'Makefile'])
            self.options.pack(side=LEFT)

        if self.project_selected == "42commandements":
            self.options = None

        if self.project_selected == "libft":
            self.options.destroy()
            self.options = Checkbar(self.window, ['author', 'forbidden-functions', 'makefile', 'norme', 'static', 'extra', 'required', 'bonus', 'benchmark', 'tests', 'libftest', 'maintest', 'moulitest', 'fillit-checker', 'libft-unit-test'])
            self.options.pack(side=LEFT)

        if self.project_selected == "fillit":
            self.options.destroy()
            self.options = Checkbar(self.window, ['author', 'forbidden-functions', 'makefile', 'norme', 'tests', 'fillit-checker'])
            self.options.pack(side=LEFT)

Now, when selected, the output gives me an error because self.options hasn't been initialized.所以我找到了一种解决方法，只需将 is_initialized 设置为 0 或 1 就可以了。

然而，复选框并没有被删除，只是不断被添加。

TL;DR: 更改时不会删除复选框。 我想要实现的是根据通过OptionMenu 选择的内容拥有不同的复选框列表

有没有更简单的方法？

Answer 1

好吧，我研究了一段时间，基于this answer 我能够让它工作。 代码如下：

from tkinter import *
import os
import sys
from tkinter import filedialog


class Checkbar(Frame):
    def __init__(self, parent=None, picks=[], side=LEFT, anchor=W):
        Frame.__init__(self, parent)
        self.vars = []
        for pick in picks:
            var = IntVar()
            chk = Checkbutton(self, text=pick, variable=var)
            chk.pack(side=side, anchor=anchor, expand=YES)
            self.vars.append(var)

    def state(self):
        return map((lambda var: var.get()), self.vars)


class Application():
    def __init__(self):
        self.window = Tk()
        self.window.title("42PyChecker")
        self.window.minsize(width=800, height=800)
        self.options_dict = {'other': ['author', 'norme', 'Makefile'],
                              'libft': ['author', 'forbidden-functions', 'makefile', 'norme', 'static', 'extra', 'required', 'bonus', 'benchmark', 'tests', 'libftest', 'maintest', 'moulitest', 'libft-unit-test'],
                              'fillit': ['author', 'forbidden-functions', 'makefile', 'norme', 'tests', 'fillit-checker'],
                              '42commandements': []}
        # @todo: Make groups like when you tick `tests` it ticks all the tests
        # @todo: Set a icon for app image
        #self.window.iconbitmap(os.path.dirname(os.path.realpath(__file__)) + "/favicon.ico")
        # @todo: Find a way to loop through gif frames to have animated logo
        logo = PhotoImage(file=os.path.dirname(os.path.realpath(__file__)) + "/logo.gif")
        Label(self.window, image=logo).pack()
        Button(self.window, text="Select Project Path", width=20, command=self.get_project_path).pack()
        self.project = StringVar(self.window)
        self.options = ['None', 'NULL']
        self.project.trace("w", self.update_options)
        dropdown = OptionMenu(self.window, self.project, *self.options_dict.keys())
        dropdown.pack()
        self.options_choices = Checkbar(self.window, self.options)
        self.options_choices.pack(side=BOTTOM)
        Button(self.window, text="Start", command=self.start).pack(side=BOTTOM)
        Button(self.window, text="Exit", command=self.close_window).pack(side=BOTTOM)
        self.window.bind('<Escape>', self.close_window_escape)

    def close_window(self):
        self.window.destroy()
        sys.exit()

    def close_window_escape(self, event):
        self.window.destroy()
        sys.exit()

    def get_project_path(self):
        self.path = filedialog.askdirectory()
        print(self.path)

    def start(self):
        print(list(self.options_choices.state()))

    def update_options(self, *args):
        self.options = self.options_dict[self.project.get()]
        self.options_choices.destroy()
        self.options_choices = Checkbar(self.window, self.options)
        self.options_choices.pack(side=BOTTOM)

    def create_window(self):
        self.window.mainloop()

它的工作方式非常简单。您有一本包含所有项目和选项的字典。当下拉列表改变时，我们更新列表，删除当前列表并打包新列表。