在 Tkinter 中为 CustomWidgets 指定事件参数

Question

我有一个 CustomNotebook 样式，每个选项卡上都有关闭按钮：

class CustomNotebook(ttk.Notebook):
    """A ttk Notebook with close buttons on each tab"""

    __initialized = False

    def __init__(self, *args, **kwargs):
        if not self.__initialized:
            self.__initialize_custom_style()
            self.__inititialized = True

        kwargs["style"] = "CustomNotebook"
        ttk.Notebook.__init__(self, *args, **kwargs)

        self._active = None

        self.bind("<ButtonPress-1>", self.on_close_press, True)
        self.bind("<ButtonRelease-1>", self.on_close_release)

    def on_close_press(self, event):
        """Called when the button is pressed over the close button"""

        element = self.identify(event.x, event.y)

        if "close" in element:
            index = self.index("@%d,%d" % (event.x, event.y))
            self.state(['pressed'])
            self._active = index
            return "break"

    def on_close_release(self, event):
        """Called when the button is released"""
        if not self.instate(['pressed']):
            return

        element =  self.identify(event.x, event.y)
        if "close" not in element:
            # user moved the mouse off of the close button
            return

        index = self.index("@%d,%d" % (event.x, event.y))

        if self._active == index:
            closed_tab_text = self.tab(index, 'text')
            # print('From CustomNotebook', closed_tab_text) # checking if it was printing the correct tab, it is
            self.forget(index)
            self.event_generate("<<NotebookTabClosed>>", data=closed_tab_text)

        self.state(["!pressed"])
        self._active = None

    def __initialize_custom_style(self):
        style = ttk.Style()
        self.images = (
            tk.PhotoImage("img_close", data='''
                R0lGODlhCAAIAMIBAAAAADs7O4+Pj9nZ2Ts7Ozs7Ozs7Ozs7OyH+EUNyZWF0ZWQg
                d2l0aCBHSU1QACH5BAEKAAQALAAAAAAIAAgAAAMVGDBEA0qNJyGw7AmxmuaZhWEU
                5kEJADs=
                '''),
            tk.PhotoImage("img_closeactive", data='''
                R0lGODlhCAAIAMIEAAAAAP/SAP/bNNnZ2cbGxsbGxsbGxsbGxiH5BAEKAAQALAAA
                AAAIAAgAAAMVGDBEA0qNJyGw7AmxmuaZhWEU5kEJADs=
                '''),
            tk.PhotoImage("img_closepressed", data='''
                R0lGODlhCAAIAMIEAAAAAOUqKv9mZtnZ2Ts7Ozs7Ozs7Ozs7OyH+EUNyZWF0ZWQg
                d2l0aCBHSU1QACH5BAEKAAQALAAAAAAIAAgAAAMVGDBEA0qNJyGw7AmxmuaZhWEU
                5kEJADs=
            ''')
        )

        style.element_create("close", "image", "img_close",
                            ("active", "pressed", "!disabled", "img_closepressed"),
                            ("active", "!disabled", "img_closeactive"), border=8, sticky='')
        style.layout("CustomNotebook", [("CustomNotebook.client", {"sticky": "nswe"})])
        style.layout("CustomNotebook.Tab", [
            ("CustomNotebook.tab", {
                "sticky": "nswe",
                "children": [
                    ("CustomNotebook.padding", {
                        "side": "top",
                        "sticky": "nswe",
                        "children": [
                            ("CustomNotebook.focus", {
                                "side": "top",
                                "sticky": "nswe",
                                "children": [
                                    ("CustomNotebook.label", {"side": "left", "sticky": ''}),
                                    ("CustomNotebook.close", {"side": "left", "sticky": ''}),
                                ]
                        })
                    ]
                })
            ]
        })
    ])

笔记本的每个选项卡都将是我的代码的输出：

class OutputNotebook:
    def __init__(self, master, **kwargs):
        self.master = master
        self.widget = CustomNotebook(master)
        self.widget.pack(pady=(8,0), anchor='ne', fill='both', expand=True)
        self.widget.bind("<<NotebookTabClosed>>", self.on_tab_closed)

    def add_table(
            self,):
        title = f"Example {len(self.widget.children)}"

        new_tab = tk.Frame(self.widget)
        tk.Label(new_tab, text= 'Place Holder Label').pack(fill="both", expand=True)
        self.widget.add(new_tab, text=title)
        self.widget.select(new_tab)

    def on_tab_closed(self, event):
        print(event.data)

问题在于，当“NotebookTabClosed”事件调用“on_tab_close”方法时，所选的小部件不是关闭的小部件。

我指定“数据”作为事件的参数仍然是，我做错了什么？我如何从活动中访问“数据”？

要亲自尝试，请复制此处的所有代码并添加以下内容：

root = tk.Tk()
notebook = OutputNotebook(root)
button = tk.Button(
    root,
    text= 'Add new Table',
    command= notebook.add_table)

button.pack(fill='x', expand=True)
notebook.widget.pack()


root.mainloop()

我现在不知道该去哪里。

Answer 1

不幸的是，这是 tkinter 中的一个错误。

Event

对象不支持

data

属性。