有没有办法在 tkinter.ttk.Notebook 的选项卡中添加关闭按钮？

Question

我想为tkinter.ttk.Notebook 中的每个选项卡添加关闭按钮。我已经尝试添加图像并对点击事件做出反应，但不幸的是BitmapImage 没有bind() 方法。

如何修复此代码？

#!/usr/binenv python3

from tkinter import *
from tkinter.ttk import *


class Application(Tk):
    def __init__(self):
        super().__init__()
        notebook = Notebook(self)
        notebook.pack(fill=BOTH, expand=True)
        self.img = BitmapImage(master=self, file='./image.xbm')
        self.img.bind('<Button-1>', self._on_click)
        notebook.add(Label(notebook, text='tab content'), text='tab caption', image=self.img)

    def _on_click(self, event):
        print('it works')

app = Application()
app.mainloop()

图像.xbm

#define bullet_width 11
#define bullet_height 9
static char bullet_bits = {
    0x00, 0x00, 0x00, 0x00, 0x78, 0x00, 0xf8, 0x00, 0xf8, 0x00, 0xf8, 0x00, 0x70, 0x00, 0x00, 0x00, 0x00, 0x00
}

Answer 1

主题 (ttk) 小部件的一个优点是您可以使用单个小部件“元素”创建新的小部件。虽然不是很简单（也没有很好的记录），但您可以创建一个新的“关闭选项卡”元素并将其添加到“选项卡”元素。

我将提出一种可能的解决方案。我承认这不是特别容易理解。在 tkdocs.com 上可以找到有关如何创建自定义小部件样式的最佳资源之一，从 Styles and Themes 部分开始。

try:
    import Tkinter as tk
    import ttk
except ImportError:  # Python 3
    import tkinter as tk
    from tkinter import ttk

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:
            self.forget(index)
            self.event_generate("<<NotebookTabClosed>>")

        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": ''}),
                                ]
                        })
                    ]
                })
            ]
        })
    ])

if __name__ == "__main__":
    root = tk.Tk()

    notebook = CustomNotebook(width=200, height=200)
    notebook.pack(side="top", fill="both", expand=True)

    for color in ("red", "orange", "green", "blue", "violet"):
        frame = tk.Frame(notebook, background=color)
        notebook.add(frame, text=color)

    root.mainloop()

这是它在 linux 系统上的样子：

Answer 2

我非常喜欢使用这段代码，谢谢！！！ 通过将构造函数修改为：修复了创建多个 Notebook 的错误：

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

希望其他人也可以利用：-)