askopenfilename() disables editing tkinter Entry [duplicate] - python-3.x

Question

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No input possible after tk
(2 answers)
Closed 4 years ago.
I'm using the following code to open a file, read its lines into a list and filter them using a substring from an Entry:
def get_entries(self):
"""
Open a file and load entries into a list.
"""
try:
# self.file_name = "p1.py"
self.file_name = askopenfilename(title="Open file")
self.file_handle = open(self.file_name, "r")
except IOError:
messagebox.showinfo("Info", "No file has been openned.")
self.destroy()
else:
self.entry_list = self.file_handle.readlines()
self.update_list()
def update_list(self, *args):
"""
Update the list after each editing of the search filter
"""
search_term = self.search_var.get()
self.lbox.delete(*self.lbox.get_children())
for index, item in enumerate(self.entry_list):
if search_term.lower() in item.lower():
self.lbox.insert('', END, values=(index, item))
Why does it work fine using self.file_name = "p1.py" but using askopenfilename() disables editing the Entry?
Minimizing and restoring the window with the Entry fixes the problem.
I'm using PyCharm on Windows 10
Here is the rest of the code for reference:
from tkinter import *
from tkinter import messagebox
from tkinter import ttk
from tkinter.filedialog import askopenfilename
class Application(Frame):
def __init__(self, master=None):
Frame.__init__(self, master)
self.pack()
self.file_name = ""
self.file_handle = ""
self.entry_list = None
self.search_label = Label(self, text="Filter: ")
self.search_var = StringVar()
self.search_var.trace("w", self.update_list)
self.search_entry = Entry(self, textvariable=self.search_var)
self.lbox = ttk.Treeview(self, columns=('indices', 'entries'), displaycolumns='entries', show='headings')
self.lbox.heading('entries', text="Entries", anchor="w")
self.confirm = Button(self, text="Confirm", width=10, command=self.confirm_action)
self.cancel = Button(self, text="Cancel", width=10, command=quit)
self.search_label.grid(row=0, column=0, sticky=E, padx=12, pady=5)
self.search_entry.grid(row=0, column=1, sticky=W, columnspan=4, pady=5)
self.lbox.grid(row=1, column=0, columnspan=3, sticky=(N, W, S, E), padx=12, pady=5)
self.cancel.grid(row=2, column=0, pady=5)
self.confirm.grid(row=2, column=1, sticky=W, padx=12, pady=5)
self.grid_columnconfigure(0, weight=1, uniform="u")
self.grid_columnconfigure(1, weight=1, uniform="u")
self.grid_columnconfigure(2, weight=4, uniform="u")
self.get_entries()
def get_entries(self): ...
def update_list(self, *args): ...
def confirm_action(self): ...
root = Tk()
root.title('Filter Listbox Test')
app = Application(master=root)
app.mainloop()

Answer 1

This seems to be a problem due to calling the askfilename before the root window is drawn. As a workaround you can add self.update() before you call askopenfilename.
class Application(Frame):
def __init__(self, master=None):
# ... stuff ...
self.update()
self.get_entries()
I'll file a bug report about this right now.