I am using Tkinter to build two windows. One the main one, pressing a button leads to the creation of the second window.
This second window does not get focus immediately when it created. That I am able to fix by calling .focus_force(). However, when I call the askdirectory() function from tkFileDialog, the focus changes back to the first window.
How can I prevent that focus switch from happening, without simply calling focus_force() all over the place?
To replicate problem:
from Tkinter import *
from tkFileDialog import *
class app:
def __init__(self, master):
Button(master, command = make_new).grid()
def make_new(self):
root = Tk()
new = new_win(root)
root.mainloop() #here the focus is on the first window
class new_win:
def __init__(self, master):
f = askdirectory() #even after placing focus on second window,
#focus goes back to first window here
I am using Python 2.7.3. Thanks!
the little-documented wm_attributes method might help:
from Tkinter import *
import tkFileDialog
root = Tk()
top = Toplevel()
top.wm_attributes('-topmost', 1)
top.withdraw()
top.protocol('WM_DELETE_WINDOW', top.withdraw)
def do_dialog():
oldFoc = top.focus_get()
print tkFileDialog.askdirectory()
if oldFoc: oldFoc.focus_set()
b0 = Button(top, text='choose dir', command=do_dialog)
b0.pack(padx=100, pady=100)
def popup():
top.deiconify()
b0.focus_set()
b1 = Button(root, text='popup', command=popup)
b1.pack(padx=100, pady=100)
root.mainloop()
Related
I am trying to create a GUI in Python 3.9.1 with tkinter and am having issues getting a default value to show in an Entry box.
from tkinter import *
from tkinter import ttk
class GUI:
def __init__(self, root, *args):
self.root = root
self.initial_frame = ttk.Frame(self.root)
self.initial_frame.grid(row=0)
ttk.Label(self.initial_frame, text="User question here?").grid(row=1, column=1)
self.ext_len = StringVar(value=4)
ext_len_entry = ttk.Entry(self.initial_frame, textvariable=self.ext_len)
ext_len_entry.grid(row=1, column=2)
root = Tk()
GUI(root)
root.mainloop()
Note: official tkinter docs say to use from tkinter import * and from tkinter import ttk.
See this link and look in the Python section in the step-by-step walkthrough https://tkdocs.com/tutorial/firstexample.html
I've also tried using self.ext_len.set(4) after initializing the entry but before putting it on the grid. I've tried self.ext_len.insert(0,4) as well.
If I add a button with a callback that does nothing, the 4 shows up in the entry box. I found that I don't even have to render it on the grid. Just initializing it is enough. A button without a callback does not work.
Working code:
from tkinter import *
from tkinter import ttk
class GUI:
def __init__(self, root, *args):
self.root = root
self.initial_frame = ttk.Frame(self.root)
self.initial_frame.grid(row=0)
ttk.Label(self.initial_frame, text="User question here?").grid(row=1, column=1)
self.ext_len = StringVar(value=4)
ext_len_entry = ttk.Entry(self.initial_frame, textvariable=self.ext_len)
ext_len_entry.grid(row=1, column=2)
ttk.Button(self.initial_frame, text="Test button", command=self.test_func)
def test_func(self, *args):
pass
root = Tk()
GUI(root)
root.mainloop()
Why does initializing the button cause it to work?
I'm prepared two files. First with GUI class. Second file is a script where I want to use a GUI, Databases and Template classes. A Databases and Template classes works. I check it in other scripts.
Questions:
How can I use event(KeyRelase) form GUI class in script?
First:
from tkinter import *
from tkinter.font import Font
from tkinter.ttk import Separator
class GUI:
def __init__(self, master):
self.ent_InventoryNumber = Entry(self.frm_FirstColumn, font=fontStyle, width=35, borderwidth=2, justify=CENTER)
self.ent_InventoryNumber.insert(END, "Wprowadź TUTAJ numer inwentarzowy")
self.ent_InventoryNumber.grid(row=2, column=0, columnspan=2, padx=5, pady=20, ipadx=2, ipady=2)
self.ent_InventoryNumber.bind("<KeyRelease>", lambda x: self.searchChamber())
def searchChamber(self):
return self.ent_InventoryNumber.get()
Second file with script:
import Databases as Db
import Template
from GUI import GUI
def test(a):
print(a)
window = Tk()
myGUI = GUI(window)
window.mainloop()
# test(myGUI.searchChamber()) ???
bind works correctly in you code. Problem is that bind can't get value which you use with return - it can't assing it to any variable and you have to use this value directly in searchChamber or assign to some variable to use it later.
Other problem: when you close window then tkinter destroy all widgets and you have to keep value from Entry in some variable
def searchChamber(self):
self.result = self.ent_InventoryNumber.get()
and later get this variable
test(GUI.result)
In this example I use print() to see if bind executes function after every pressed key. I also use class variable self.result to keep value and use it after closing window.
GUI.py
import tkinter as tk
class GUI:
def __init__(self, master):
self.result = '' # default value as start
self.ent_InventoryNumber = tk.Entry(master)
self.ent_InventoryNumber.insert('end', "Wprowadź TUTAJ numer inwentarzowy")
self.ent_InventoryNumber.grid(row=2, column=0)
self.ent_InventoryNumber.bind("<KeyRelease>", self.searchChamber)
def searchChamber(self, event=None):
self.result = self.ent_InventoryNumber.get()
print('[DEBUG] searchChamber:', self.result)
main.py
import tkinter as tk
from GUI import GUI
window = tk.Tk()
myGUI = GUI(window)
window.mainloop()
print('result:', myGUI.result)
I created a button that works perfectly (not entire code here) but I want that once you press the 'Save' button, the window disappear. Someone knows how to do it?
root2 = tk.Tk()
root2.geometry('200x100')
save_button = tk.Button(root2)
save_button.configure(text='Save', command=lambda: ask_parameter(ents1))
save_button.pack()
root2.mainloop()
Based on the extremely limited snippet of code in your question: I would suggest it doing by defining a function to call that does something like this:
import tkinter as tk
def ask_and_close(root, ents):
ask_parameter(ents)
root.destroy()
ents1 = "something"
root2 = tk.Tk()
root2.geometry('200x100')
save_button = tk.Button(root2)
save_button.configure(text='Save', command=lambda: ask_and_close(root2, ents1))
save_button.pack()
root2.mainloop()
Note: If you're creating multiple windows, I wouild suggest using tk.Toplevel() instead of calling tk.TK() more than once.
Just use the master.quit() method!
Example Code:
from tkinter import *
class Test:
def __init__(self):
self.master = Tk()
self.button = Button(self.master, text="Push me!", command=self.closeScreen)
self.button.pack()
def closeScreen(self):
# In your case, you need "root2.quit"
self.master.quit()
test = Test()
mainloop()
I would suggest using destroy() method as used here https://docs.python.org/3.8/library/tkinter.html#a-simple-hello-world-program.
One of the easy ways to invoke the destroy method in your code is this;
def ask_parameter_and_destroy(ents1):
ask_parameter(ents1)
root2.destroy()
root2 = tk.Tk()
root2.geometry('200x100')
save_button = tk.Button(root2)
save_button.configure(text='Save', command=lambda: ask_parameter_and_destroy(ents1))
save_button.pack()
root2.mainloop()
You can read about differences between destroy() and previously proposed quit() methods on the following page: What is the difference between root.destroy() and root.quit()?.
If your goal is to create a dialog for saving a file, you might be interested in tkinter.filedialog library, which has ready made dialog boxes for handling file saving.
I am working on code in tkinter python v3.7 where I want to open a new window which has same functionalities like original window. How can I do that?
While searching for solution I came across function naming Toplevel which creates new tkinter window. But this new window is completely new, It doesn't have functionalities(Button, geometry size in my case) which were provided in original one.
from tkinter import *
class TextPad:
def new_window(self):
top = Toplevel()
def __init__(self, master):
master.title('Text Pad')
master.geometry('400x400')
self.button = Button(master, text='Press',
command=self.new_window)
self.button.pack()
root = Tk()
t = TextPad(root)
root.mainloop()
My original window has geometry size of '400x400' and It has 'button', I want to open a new window having this functionalities.
I assume you want two (or more) windows at the same time.
If you want identical window then use again TextPad()
but this time use Toplevel() instead of Tk()
def new_window(self):
top = TextPad(Toplevel())
and don't run second mainloop()
If you want replace first window by new window - to have alwasy only one window - then you would have to destroy old window and then create new one using TextPad() with Tk() and mainloop()
But it would need to use self.master instead of master to have access to master in method new_window
from tkinter import *
class TextPad:
def new_window(self):
self.master.destroy()
root = Tk()
t = TextPad(root)
root.mainloop()
def __init__(self, master):
self.master = master
self.master.title('Text Pad')
self.master.geometry('400x400')
self.button = Button(self.master, text='Press',
command=self.new_window)
self.button.pack()
root = Tk()
t = TextPad(root)
root.mainloop()
I am starting to learn Python and the tkinter package and I am writing a program to load a text file on the GUI window. To open the file browser, I installed the button and its necessary function as shown in the below code. The program runs but when I click on the "browse" button, I am getting an attribute error saying : "'assign_1' object has no attribute 'var_filename'". It would be great if anyone could help me with this.
from tkinter import *
from tkinter import messagebox
from tkinter import simpledialog
from tkinter import filedialog
from math import *
from numpy import *
import string
root = Tk()
def close_window_callback(root):
if messagebox.askokcancel("Quit", "Do you really wish to quit?"):
root.destroy()
class assign_1:
def __init__(self,master):
self.master = master
frame = Frame(master)
frame.pack()
self.canvas = Canvas(master,width=1000,height=1000, bg="yellow")
self.button_browse = Button(frame, text="Browse",
command=self.browse_file)
self.button_browse.pack()
self.button_load = Button(frame, text="Load")
self.button_load.pack(side = LEFT)
self.canvas.pack(expand=YES, fill=BOTH)
def browse_file(self):
self.var_filename.set(filedialog.askopenfilename(filetypes=[("allfiles","*"),("pythonfiles","*.txt")]))
filename = self.var_filename.get()
print(filename)
root.protocol("WM_DELETE_WINDOW", lambda root_window=root: close_window_callback(root_window))
assign_1(root)
root.mainloop()
Although, as Rinzler pointed out, your indentation is wrong in the code you posted, that would lead to another error (AttributeError: assign_1 instance has no attribute 'browse_file'). So I'm guessing the indentation in the code you actually use is correct.
The problem is that you try to use self.var_filename.set(...) without having defined what self.var_filename is. If you want it to be a StringVar, which seems to be the case since you use set and get, you have to initialize it. To do this you should put self.var_filename = StringVar(master) in the class' __init__ function. A small example demonstrating this:
root = Tk()
class assign_1:
def __init__(self, master):
self.master = master
self.var_filename = StringVar(master)
self.button_browse = Button(master, text="Browse", command=self.browse_file)
self.button_browse.pack()
def browse_file(self):
self.var_filename.set(filedialog.askopenfilename(filetypes=[("allfiles","*"),("pythonfiles","*.txt")]))
filename = self.var_filename.get()
print(filename)
assign_1(root)
root.mainloop()
However, from the looks of it, in your case there is no need to use a tkinter StringVar, just use a normal string variable:
root = Tk()
class assign_1:
def __init__(self, master):
self.master = master
self.button_browse = Button(master, text="Browse", command=self.browse_file)
self.button_browse.pack()
def browse_file(self):
self.filename = filedialog.askopenfilename(filetypes=[("allfiles","*"),("pythonfiles","*.txt")])
print(self.filename)
assign_1(root)
root.mainloop()
The indentation is wrong. The function browse_file you wanted to define as method of the class assign_1 (use capitalise letters to declare name of classes) is a global function as you defined it.
You have also not defined self.var_filename anywhere, so it will then give you the error:
AttributeError: 'assign_1' object has no attribute 'var_filename'
Under the function close_window_callback, you have also wrong indentation.