Why is selection_clear() in Entry of tkinter invalid?

Question

I want to realize "Cut" in Rightkey menu by the following code:

self.entry_title = entry(frm, RIGHT, self.title, width = 58)
def menubarCut(self):
    if not self.entry_title.selection_present():
        showerror('***', 'No text selected')
    else:
        text = self.entry_title.selection_get()
        self.entry_title.selection_clear()
        self.clipboard_clear()
        self.clipboard_append(text)

However, menubarCut returns the effect of "Copy" instead of "Cut". Namely, the results returned by the above code is the same as that returned by the following code:

self.entry_title = entry(frm, RIGHT, self.title, width = 58)
def menubarCopy(self):
    if not self.entry_title.selection_present():
        showerror('***', 'No text selected')
    else:
        text = self.entry_title.selection_get()
        self.clipboard_clear()
        self.clipboard_append(text)

It seems that self.entry_title.selection_clear() has no effect. Why does that happen? How can I solve this problem?

Answer 1

Based on @BryanOakley's answer to tkinter copy-pasting to Entry doesn't remove selected text, I would guess this is what you want:

def menubarCut(self):
    if self.entry_title.selection_present():
        text = self.entry_title.selection_get()
        self.entry_title.delete("sel.first", "sel.last")
        self.clipboard_clear()
        self.clipboard_append(text)
    else:
        showerror('***', 'No text selected')

The selection_clear() method clears the act of selection (the highlighting) not the actual text that's selected. FYI, here's the MCVE I created to test this:

import sys
import tkinter as tk

class Application(tk.Frame):

    def __init__(self, master=None):
        super().__init__(master)

        self.entry_title = tk.Entry(master, width=50)
        self.entry_title.pack()

        self.entry_title.bind('<Escape>', self.event_handler)

    def menubarCut(self):
        if self.entry_title.selection_present():
            text = self.entry_title.selection_get()
            self.entry_title.delete("sel.first", "sel.last")
            self.clipboard_clear()
            self.clipboard_append(text)
        else:
            print('No text selected', file=sys.stdderr)

    def event_handler(self, event):
        self.menubarCut()

root = tk.Tk()
Application(root)
root.mainloop()