python - tkinter 应用程序添加右键单击上下文菜单？

Question

我有一个 python-tkinter gui 应用程序，我一直在尝试找到某种方法来添加一些功能。我希望有一种方法可以右键单击应用程序列表框区域中的项目并调出上下文菜单。tkinter 能够做到这一点吗？我会更好地研究 gtk 或其他一些 gui-toolkit 吗？

Answer 1

您将创建一个Menu实例并编写一个调用
其post()ortk_popup()方法的函数。

tkinter文档目前没有任何关于tk_popup().
阅读Tk 文档以获取描述或来源：

library/menu.tcl在 Tcl/Tk 源代码中：

::tk_popup --
此过程弹出一个菜单并设置遍历
菜单及其子菜单。

论据：
menu - 要弹出的菜单的名称。
x, y - 弹出菜单的根坐标。  
entry - 以 (x,y) 为中心的菜单项的索引。  
        如果省略或指定为 {}，则菜单的  
        左上角在 (x,y) 处。  

tkinter/__init__.py在 Python 源代码中：

def tk_popup(self, x, y, entry=""):
    """Post the menu at position X,Y with entry ENTRY."""
    self.tk.call('tk_popup', self._w, x, y, entry)

您将上下文菜单调用函数与右键单击相关联：
the_widget_clicked_on.bind("<Button-3>", your_function)。

但是，与右键单击相关的数字在每个平台上都不相同。

library/tk.tcl在 Tcl/Tk 源代码中：

在 Darwin/Aqua 上，从左到右的按钮是 1,3,2。  
在以最近的 XQuartz 作为 X 服务器的 Darwin/X11 上，它们是 1、2、3；
其他 X 服务器可能会有所不同。

这是我编写的一个示例，它向列表框添加了上下文菜单：

import tkinter # Tkinter -> tkinter in Python 3

class FancyListbox(tkinter.Listbox):

    def __init__(self, parent, *args, **kwargs):
        tkinter.Listbox.__init__(self, parent, *args, **kwargs)

        self.popup_menu = tkinter.Menu(self, tearoff=0)
        self.popup_menu.add_command(label="Delete",
                                    command=self.delete_selected)
        self.popup_menu.add_command(label="Select All",
                                    command=self.select_all)

        self.bind("<Button-3>", self.popup) # Button-2 on Aqua

    def popup(self, event):
        try:
            self.popup_menu.tk_popup(event.x_root, event.y_root, 0)
        finally:
            self.popup_menu.grab_release()

    def delete_selected(self):
        for i in self.curselection()[::-1]:
            self.delete(i)

    def select_all(self):
        self.selection_set(0, 'end')


root = tkinter.Tk()
flb = FancyListbox(root, selectmode='multiple')
for n in range(10):
    flb.insert('end', n)
flb.pack()
root.mainloop()

The use of grab_release() was observed in an example on effbot.
Its effect might not be the same on all systems.

Answer 2

I made some changes to the conext menu code above in order to adjust my demand and I think it would be useful to share:

Version 1:

import tkinter as tk
from tkinter import ttk

class Main(tk.Frame):
    def __init__(self, master):
        tk.Frame.__init__(self, master)
        master.geometry('500x350')
        self.master = master
        self.tree = ttk.Treeview(self.master, height=15)
        self.tree.pack(fill='x')
        self.btn = tk.Button(master, text='click', command=self.clickbtn)
        self.btn.pack()
        self.aMenu = tk.Menu(master, tearoff=0)
        self.aMenu.add_command(label='Delete', command=self.delete)
        self.aMenu.add_command(label='Say Hello', command=self.hello)
        self.num = 0

        # attach popup to treeview widget
        self.tree.bind("<Button-3>", self.popup)

    def clickbtn(self):
        text = 'Hello ' + str(self.num)
        self.tree.insert('', 'end', text=text)
        self.num += 1

    def delete(self):
        print(self.tree.focus())
        if self.iid:
            self.tree.delete(self.iid)

    def hello(self):
        print ('hello!')

    def popup(self, event):
        self.iid = self.tree.identify_row(event.y)
        if self.iid:
            # mouse pointer over item
            self.tree.selection_set(self.iid)
            self.aMenu.post(event.x_root, event.y_root)            
        else:
            pass

root = tk.Tk()
app=Main(root)
root.mainloop()

Version 2:

import tkinter as tk
from tkinter import ttk

class Main(tk.Frame):
    def __init__(self, master):
        master.geometry('500x350')
        self.master = master
        tk.Frame.__init__(self, master)
        self.tree = ttk.Treeview(self.master, height=15)
        self.tree.pack(fill='x')
        self.btn = tk.Button(master, text='click', command=self.clickbtn)
        self.btn.pack()
        self.rclick = RightClick(self.master)
        self.num = 0

        # attach popup to treeview widget
        self.tree.bind('<Button-3>', self.rclick.popup)
    def clickbtn(self):
        text = 'Hello ' + str(self.num)
        self.tree.insert('', 'end', text=text)
        self.num += 1

class RightClick:
    def __init__(self, master):
       
        # create a popup menu
        self.aMenu = tk.Menu(master, tearoff=0)
        self.aMenu.add_command(label='Delete', command=self.delete)
        self.aMenu.add_command(label='Say Hello', command=self.hello)

        self.tree_item = ''

    def delete(self):
        if self.tree_item:
            app.tree.delete(self.tree_item)

    def hello(self):
        print ('hello!')

    def popup(self, event):
        self.aMenu.post(event.x_root, event.y_root)
        self.tree_item = app.tree.focus()

root = tk.Tk()
app=Main(root)
root.mainloop()

Answer 3

from tkinter import *
root=Tk()
root.geometry("500x400+200+100")

class Menu_Entry(Entry):
    def __init__(self,perant,*args,**kwargs):
        Entry.__init__(self,perant,*args,**kwargs)
        self.popup_menu=Menu(self,tearoff=0,background='#1c1b1a',fg='white',
                                     activebackground='#534c5c',
                             activeforeground='Yellow')
        self.popup_menu.add_command(label="Cut                     ",command=self.Cut,
                                    accelerator='Ctrl+V')
        self.popup_menu.add_command(label="Copy                    ",command=self.Copy,compound=LEFT,
                                    accelerator='Ctrl+C')
    
        self.popup_menu.add_command(label="Paste                   ",command=self.Paste,accelerator='Ctrl+V')
        self.popup_menu.add_separator()
        self.popup_menu.add_command(label="Select all",command=self.select_all,accelerator="Ctrl+A")
        self.popup_menu.add_command(label="Delete",command=self.delete_only,accelerator=" Delete")
        self.popup_menu.add_command(label="Delete all",command=self.delete_selected,accelerator="Ctrl+D")
        self.bind('<Button-3>',self.popup)
        self.bind("<Control-d>",self.delete_selected_with_e1)
        self.bind('<App>',self.popup)
        self.context_menu = Menu(self, tearoff=0)
        self.context_menu.add_command(label="Cut")
        self.context_menu.add_command(label="Copy")
        self.context_menu.add_command(label="Paste")
         
    def popup(self, event):
      try:
        self.popup_menu.tk_popup(event.x_root, event.y_root, 0)
      finally:
        self.popup_menu.grab_release()

    def Copy(self):
      self.event_generate('<<Copy>>')

    def Paste(self):
      self.event_generate('<<Paste>>')

    def Cut(self):
      self.event_generate('<<Cut>>')

    def delete_selected_with_e1(self,event):
      self.select_range(0, END)
      self.focus()
      self.event_generate("<Delete>")

    def delete_selected(self):
      self.select_range(0, END)
      self.focus()
      self.event_generate("<Delete>")

    def delete_only(self):
      self.event_generate("<BackSpace>")

    def select_all(self):
      self.select_range(0, END)
      self.focus()



ent=Menu_Entry(root)
ent.pack()


root.mainloop()

Answer 4

Important Caveat:

(Assuming the event argument that contains the coordinates is called "event"): Nothing will happen or be visible when you call tk_popup(...) unless you use "event.x_root" and "event.y_root" as arguments. If you do the obvious of using "event.x" and "event.y", it won't work, even though the names of the coordinates are "x" and "y" and there is no mention of "x_root" and "y_root" anywhere within it.

As for the grab_release(..), it's not necessary, anywhere. "tearoff=0" also isn't necessary, setting it to 1 (which is default), simply adds a dotted line entry to the context menu. If you click on it, it detaches the context menu and makes it its own top-level window with window decorators. tearoff=0 will hide this entry. Moreover, it doesn't matter if you set the menu's master to any specific widget or root, or anything at all.