Python tkinter/ ttkboostrap dateentry não funciona quando no estado somente leitura

Você não deve editar o código do ttkbootstrap. Ele seria substituído na próxima atualização.

Você pode simplesmente criar uma nova classe herdando de DateEntry, definindo o estado da entrada no init e habilitando o campo somente quando você pressionar o botão:

import ttkbootstrap as tb

class CustomDateEntry(tb.DateEntry):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.entry["state"] = "readonly"

    def _on_date_ask(self):
        self.entry["state"] = "normal"
        super()._on_date_ask()
        self.entry["state"] = "readonly"

root = tb.Window()
date_entry = CustomDateEntry(root)
date_entry.pack(padx = 10, pady = 10)

root.mainloop()

Editar: chamando super()._on_date_ask()em vez de escrever uma nova função, conforme sugerido por @acw1668.

O estado readonly faz com que a data só possa ser lida e não alterada/editada, então define-a como a data atual, bastante autoexplicativo, eu acho, minha pergunta seria por que não apenas se livrar da linha somente leitura desde o usuário ainda pode selecionar a data através do pop-up do calendário?

Ok, acabei de entrar no código-fonte do ttkbootstrap DateEntry e copiar a classe e também a classe Querybox. Para evitar esse problema, expliquei que encontrei uma coisa, você deve vincular a entrada de data a uma variável de texto global. Então você pode alternar todos entry.insert(...) com o textvariable.set(...). Você também precisa transformar todas as inserções na textvariable.get(...)classe Querybox copiada.

Aqui está a classe DateEntry:

class DateEntry_test(ttk.Frame):
    """A date entry widget combines the `Combobox` and a `Button`
    with a callback attached to the `get_date` function.

    When pressed, a date chooser popup is displayed. The returned
    value is inserted into the combobox.

    The date chooser popup will use the date in the combobox as the
    date of focus if it is in the format specified by the
    `dateformat` parameter. By default, this format is "%Y-%m-%d".

    The bootstyle api may be used to change the style of the widget.
    The available colors include -> primary, secondary, success,
    info, warning, danger, light, dark.

    The starting weekday on the date chooser popup can be changed
    with the `firstweekday` parameter. By default this value is
    `6`, which represents "Sunday".

    The `Entry` and `Button` widgets are accessible from the
    `DateEntry.Entry` and `DateEntry.Button` properties.

    ![](../../assets/widgets/date-entry.png)
    """

    def __init__(
        self,
        master=None,
        dateformat=r"%x",
        firstweekday=6,
        startdate=None,
        bootstyle="",
        **kwargs,
    ):
        """
        Parameters:

            master (Widget, optional):
                The parent widget.

            dateformat (str, optional):
                The format string used to render the text in the entry
                widget. For more information on acceptable formats, see https://strftime.org/

            firstweekday (int, optional):
                Specifies the first day of the week. 0=Monday, 1=Tuesday,
                etc...

            startdate (datetime, optional):
                The date that is in focus when the widget is displayed. Default is
                current date.

            bootstyle (str, optional):
                A style keyword used to set the focus color of the entry
                and the background color of the date button. Available
                options include -> primary, secondary, success, info,
                warning, danger, dark, light.

            **kwargs (Dict[str, Any], optional):
                Other keyword arguments passed to the frame containing the
                entry and date button.
        """
        self._dateformat = dateformat
        self._firstweekday = firstweekday

        self._startdate = startdate or datetime.today()
        self._bootstyle = bootstyle
        super().__init__(master, **kwargs)

        # add visual components
        entry_kwargs = {"bootstyle": self._bootstyle}
        if "width" in kwargs:
            entry_kwargs["width"] = kwargs.pop("width")
        self.textvariable = tk.StringVar()
        self.entry = ttk.Entry(self, textvariable=self.textvariable, **entry_kwargs)
        
        self.entry.pack(side=tk.LEFT, fill=tk.X, expand=tk.YES)

        self.button = ttk.Button(
            master=self,
            command=self._on_date_ask,
            bootstyle=f"{self._bootstyle}-date",
        )
        self.button.pack(side=tk.LEFT)

        # starting value
        self.textvariable.set(self._startdate.strftime(self._dateformat))

    def __getitem__(self, key: str):
        return self.configure(cnf=key)

    def __setitem__(self, key: str, value):
        self.configure(cnf=None, **{key: value})

    def _configure_set(self, **kwargs):
        """Override configure method to allow for setting custom
        DateEntry parameters"""

        if "state" in kwargs:
            state = kwargs.pop("state")
            if state in ["readonly", "invalid"]:
                self.entry.configure(state=state)
            elif state in ("disabled", "normal"):
                self.entry.configure(state=state)
                self.button.configure(state=state)
            else:
                kwargs[state] = state
        if "dateformat" in kwargs:
            self._dateformat = kwargs.pop("dateformat")
        if "firstweekday" in kwargs:
            self._firstweekday = kwargs.pop("firstweekday")
        if "startdate" in kwargs:
            self._startdate = kwargs.pop("startdate")
        if "bootstyle" in kwargs:
            self._bootstyle = kwargs.pop("bootstyle")
            self.entry.configure(bootstyle=self._bootstyle)
            self.button.configure(bootstyle=[self._bootstyle, "date"])
        if "width" in kwargs:
            width = kwargs.pop("width")
            self.entry.configure(width=width)

        super(ttk.Frame, self).configure(**kwargs)

    def _configure_get(self, cnf):
        """Override the configure get method"""
        if cnf == "state":
            entrystate = self.entry.cget("state")
            buttonstate = self.button.cget("state")
            return {"Entry": entrystate, "Button": buttonstate}
        if cnf == "dateformat":
            return self._dateformat
        if cnf == "firstweekday":
            return self._firstweekday
        if cnf == "startdate":
            return self._startdate
        if cnf == "bootstyle":
            return self._bootstyle
        else:
            return super(ttk.Frame, self).configure(cnf=cnf)

    def configure(self, cnf=None, **kwargs):
        """Configure the options for this widget.

        Parameters:

            cnf (Dict[str, Any], optional):
                A dictionary of configuration options.

            **kwargs:
                Optional keyword arguments.
        """
        if cnf is not None:
            return self._configure_get(cnf)
        else:
            return self._configure_set(**kwargs)

    def _on_date_ask(self):
        """Callback for pushing the date button"""
        _val = self.entry.get() or datetime.today().strftime(self._dateformat)
        try:
            self._startdate = datetime.strptime(_val, self._dateformat)
        except Exception as e:
            print("Date entry text does not match", self._dateformat)
            self._startdate = datetime.today()
            self.entry.delete(first=0, last=tk.END)
            self.textvariable.set(self._startdate.strftime(self._dateformat))

        old_date = datetime.strptime(_val, self._dateformat)

        # get the new date and insert into the entry
        new_date = Querybox_test.get_date(
            parent=self.entry,
            startdate=old_date,
            firstweekday=self._firstweekday,
            bootstyle=self._bootstyle,
        )
        self.entry.delete(first=0, last=tk.END)
        self.textvariable.set(new_date.strftime(self._dateformat))
        self.entry.focus_force()

e a classe Querybox:

class Querybox_test:
    """This class contains various static methods that request data
    from the end user."""

    @staticmethod
    def get_color(
        parent=None, title="Color Chooser", initialcolor=None, **kwargs
    ):
        """Show a color picker and return the select color when the
        user pressed OK.

        ![](../../assets/dialogs/querybox-get-color.png)

        Parameters:

            parent (Widget):
                The parent widget.

            title (str):
                Optional text that appears on the titlebar.

            initialcolor (str):
                The initial color to display in the 'Current' color
                frame.

        Returns:

            Tuple[rgb, hsl, hex]:
                The selected color in various colors models.
        """
        from ttkbootstrap.dialogs.colorchooser import ColorChooserDialog

        dialog = ColorChooserDialog(parent, title, initialcolor)
        if "position" in kwargs:
            position = kwargs.pop("position")
        else:
            position = None
        dialog.show(position)
        return dialog.result

    @staticmethod
    def get_date(
        parent=None,
        title=" ",
        firstweekday=6,
        startdate=None,
        bootstyle="primary",
    ):
        """Shows a calendar popup and returns the selection.

        ![](../../assets/dialogs/querybox-get-date.png)

        Parameters:

            parent (Widget):
                The parent widget; the popup will appear to the
                bottom-right of the parent widget. If no parent is
                provided, the widget is centered on the screen.

            title (str):
                The text that appears on the popup titlebar.

            firstweekday (int):
                Specifies the first day of the week. `0` is Monday, `6` is
                Sunday (the default).

            startdate (datetime):
                The date to be in focus when the widget is displayed;

            bootstyle (str):
                The following colors can be used to change the color of the
                title and hover / pressed color -> primary, secondary, info,
                warning, success, danger, light, dark.

        Returns:

            datetime:
                The date selected; the current date if no date is selected.
        """
        chooser = DatePickerDialog(
            parent=parent,
            title=title,
            firstweekday=firstweekday,
            startdate=startdate,
            bootstyle=bootstyle,
        )
        return chooser.date_selected

    @staticmethod
    def get_string(
        prompt="", title=" ", initialvalue=None, parent=None, **kwargs
    ):
        """Request a string type input from the user.

        ![](../../assets/dialogs/querybox-get-string.png)

        Parameters:

            prompt (str):
                A message to display in the message box above the entry
                widget.

            title (str):
                The string displayed as the title of the message box. This
                option is ignored on Mac OS X, where platform guidelines
                forbid the use of a title on this kind of dialog.

            initialvalue (Any):
                The initial value in the entry widget.

            parent (Widget):
                Makes the window the logical parent of the message box. The
                messagebox is displayed on top of its parent window.

            **kwargs (Dict):
                Other optional keyword arguments.

        Returns:

            str:
                The string value of the entry widget.
        """
        initialvalue = initialvalue or ""
        if "position" in kwargs:
            position = kwargs.pop("position")
        else:
            position = None
        dialog = QueryDialog(
            prompt, title, initialvalue, parent=parent, **kwargs
        )
        dialog.show(position)
        return dialog._result

    @staticmethod
    def get_integer(
        prompt="",
        title=" ",
        initialvalue=None,
        minvalue=None,
        maxvalue=None,
        parent=None,
        **kwargs,
    ):
        """Request an integer type input from the user.

        ![](../../assets/dialogs/querybox-get-integer.png)

        Parameters:

            prompt (str):
                A message to display in the message box above the entry
                widget.

            title (str):
                The string displayed as the title of the message box. This
                option is ignored on Mac OS X, where platform guidelines
                forbid the use of a title on this kind of dialog.

            initialvalue (int):
                The initial value in the entry widget.

            minvalue (int):
                The minimum allowed value.

            maxvalue (int):
                The maximum allowed value.

            parent (Widget):
                Makes the window the logical parent of the message box. The
                messagebox is displayed on top of its parent window.

            **kwargs (Dict):
                Other optional keyword arguments.

        Returns:

            int:
                The integer value of the entry widget.
        """
        initialvalue = initialvalue or ""
        if "position" in kwargs:
            position = kwargs.pop("position")
        else:
            position = None
        dialog = QueryDialog(
            prompt,
            title,
            initialvalue,
            minvalue,
            maxvalue,
            datatype=int,
            parent=parent,
            **kwargs,
        )
        dialog.show(position)
        return dialog._result

    @staticmethod
    def get_float(
        prompt="",
        title=" ",
        initialvalue=None,
        minvalue=None,
        maxvalue=None,
        parent=None,
        **kwargs,
    ):
        """Request a float type input from the user.

        ![](../../assets/dialogs/querybox-get-float.png)

        Parameters:

            prompt (str):
                A message to display in the message box above the entry
                widget.

            title (str):
                The string displayed as the title of the message box. This
                option is ignored on Mac OS X, where platform guidelines
                forbid the use of a title on this kind of dialog.

            initialvalue (float):
                The initial value in the entry widget.

            minvalue (float):
                The minimum allowed value.

            maxvalue (float):
                The maximum allowed value.

            parent (Widget):
                Makes the window the logical parent of the message box. The
                messagebox is displayed on top of its parent window.

            **kwargs (Dict):
                Other optional keyword arguments.

        Returns:

            float:
                The float value of the entry widget.
        """
        initialvalue = initialvalue or ""
        if "position" in kwargs:
            position = kwargs.pop("position")
        else:
            position = None
        dialog = QueryDialog(
            prompt,
            title,
            initialvalue,
            minvalue,
            maxvalue,
            datatype=float,
            parent=parent,
            **kwargs,
        )
        dialog.show(position)
        return dialog._result

    @staticmethod
    def get_font(parent=None, **kwargs):
        """Request a customized font

        ![](../../assets/dialogs/querybox-get-font.png)

        Parameters:

            parent (Widget):
                Makes the window the logical parent of the dialog box. The
                dialog is displayed on top of its parent window.

            **kwargs (Dict):
                Other keyword arguments.

        Returns:

            Font:
                A font object.
        """
        if "position" in kwargs:
            position = kwargs.pop("position")
        else:
            position = None
        dialog = FontDialog(parent=parent, **kwargs)
        dialog.show(position)
        return dialog.result