Tkinter Browse Button Self Deleting - python

I am trying to create a browse button in tkinter. I have created the open folder dialog box but when i set it to the button it will exit out of the window.
My ultimate goal is to:
1) click on the button and bring up the file dialogue box
2) select a file
3) insert the file name into an Entry Widget for later use
I should note that I am using multiple window frames for the code that follows is summed up.
import os
import sys
import Tkinter as tk
from tkFileDialog import askopenfilename
def openFile(entryWidgetName):
tk.Tk().withdraw()
filename = askopenfilename()
entryWidgetName.delete(0,tk.END)
entryWidgetName.insert(0,filename)
return
class Welcome():
def __init__(self,master):
self.buttonNewTemplate = tk.Button(self.master, text = 'Create a New Template', command = self.gotoNewTemplate).place(x=100, y=250)
def gotoNewTemplate(self):
root2 = tk.Toplevel(self.master)
newTemplate = NewTemplate(root2)
class NewTemplate():
def __init__(self, master):
#Entry Windows
self.uploadFile = tk.Entry(self.sectionFrame2, width = 80).grid(row=4, column = 1, sticky = 'w')
#Buttons
self.buttonBrowse=tk.Button(self.sectionFrame2, text='Browse', fg='blue', command=lambda:openFile(uploadFile)).grid(row=4, column = 0, padx = 10, sticky = 'w')
Every time I click the browse button the second window destroys itself bringing me back to the main page.
Does anyone have any suggestions?

A tkinter application can only have a single instance of Tk. You are creating at least two: one explicitly in openFile, and one from somewhere else in your code either implicitly or explicitly.
Since the only way to call openFile is from a button click, and the only way to have a button click is to have a button, and the only way to have a button is to already have a root window, you need to remove the statement tk.Tk().withdraw() since that is creating a new root window.
There may be other problems in your code, but it's impossible to know based on the incomplete code in the question.

Related

How to pop up an existing window by using Tkinter python?

I have created a vocabulary journal by using Tkinter, and I am struggling to pop a window that i created already.
Since i am a beginner, I have not really used class everywhere..
project/build/gui.py
def open_new():# button command
print("clicked")
button_1 = Button(
image=button_image_1,
borderwidth=0,
highlightthickness=0,
command=open_new,
relief="flat"
)
I have created another window in another directory
project/build/build2/gui.py
from db import Database
from pathlib import Path
from tkinter import messagebox
from tkinter import Tk, Canvas, Entry, Text, Button, PhotoImage,Frame
ob=Database('store.db')
def add_values():
if entry_1.get()=='' or entry_2.get()=='':
messagebox.showerror('no value','please enter anu words')
return
ob.insert(entry_1.get(),entry_2.get())
# print(ob.fetch())
messagebox.showinfo("value has been added", "successfully added")
window = Tk()
blah blah
....
window.mainloop()
WhatI want to do is pop up the second module, which is actually a window. I do not think , it is possible to pop up this window by using toplevel(), is it?
So which code should i use to pop up it?

Is there a way to reopen a window after closing it using destroy() in tkinter?

window6.after(1,lambda:window6.destroy())
is what I've been using to close my windows, is there any way to get them back after doing this?
basically, is there something that is the opposite of this?
ps. these are the libraries that I've imported, if it helps in any way
import tkinter as tk
from tkinter import *
import time
from tkinter import ttk
Is there a way to reopen a window after closing it using destroy() in tkinter?
The short answer is "no". Once it has been destroyed, it is impossible to get back. You should either create the window via a frame or class so that it's easy to recreate, or hide the window by calling .withdraw() rather than .destroy().
If you put the window code into a class or a function then after destroying it you can create a new instance of it by
1: creating a new instance of the class with the window code in the init function
2: call the function the has the code for the window
By doing this you are essentially creating a new instance of the program, but without initiating the script.
from tkinter impot *
from tkinter import ttk
#creating window function, not class
def main_window():
#window code here
root = Tk()
Label(root, text = "Hello World").pack()
#destroying main window
root.destroy()
root.mainloop()
main_window()
Of course, there are a few hurdles such as the window shutting down as soon as it opens, but this is to show that you can create a new instance of a window from your program.
You can wait for user input to see whether or not the window will open or close.
If you took an OOP approach, you can pass a reference to the Parent Widget as argument to the New_Window and store it in a class attribute.
You´ll have a two way reference: Parent knows child and child knows parent.
Then you can set the Parent Reference to the New_Window to None, from within the child Widget self.parent.new_window = None in a close_me() method right after you call self.destroy() on the New_Window:
1st Bonus: this code prevents the opening of more than 1 instance of a Window at a time. You won´t get more than 1 New_Window on the screen. I don´t think having two loggin windows opened or two equal options window makes sense.
2nd Bonus: It is possible to close the window from other parts of the code, as in a MVC patter, the Controller can close the window after doing some processing.
Here´s a working example:
import tkinter as tk
class Toolbar(tk.Frame):
'''Toolbar '''
def __init__(self, master, *args, **kwargs):
super().__init__(master, *args, **kwargs)
# to store the New Window reference
self.new_window = None
self.button_new_window = tk.Button(self, text = 'New Window', command = lambda : self.get_window(self))
self.configure_grid()
def configure_grid(self):
'''Configures the Grid layout'''
self.grid(row=1, column=0, columnspan=3, sticky=(tk.N,tk.S,tk.E,tk.W))
self.button_new_window.grid(row = 2, column = 2, padx=5, pady=5)
def get_window(self, parent):
''' If window exists, return it, else, create it'''
self.new_window = self.new_window if self.new_window else Window(parent)
return self.new_window
class Window(tk.Toplevel):
'''Opens a new Window.
#param parent -- tk.Widget that opens/reference this window
'''
def __init__ (self, parent : tk.Widget):
# Stores reference to the Parent Widget, so you can set parent.new_window = None
self.parent = parent
super().__init__(master = parent.master)
self.title('New Window')
self.button_dummy = tk.Button(self, text = 'Do the thing', width = 25, command = lambda : print("Button pressed on window!"))
self.button_close = tk.Button(self, text = 'Close', width = 25, command = self.close_me)
self.configure_grid()
def configure_grid(self):
'''Grid'''
self.button_dummy.grid(row = 1, column = 0)
self.button_close.grid(row = 2, column = 0)
def close_me(self):
'''Tkinter widgets are made of two parts. 1. The python Object and 2. The GUI Widget.
The destroy() method gets rid of the widget part, but leaves the object in memory.
To also destroy the object, you need to set all of its references count to ZERO on
the Parent Widget that created the new Window, so the Garbage Collector can collect it.
'''
# Destroys the Widget
self.destroy()
# Decreasses the reference count on the Parent Widget so the Garbage Collector can destroy the python object
self.parent.new_window = None
if __name__ == '__main__':
root = tk.Tk()
toolbar = Toolbar(root)
root.mainloop()
I don´t know if this: .destroy() and re-instantiate approach is more efficient than the .withdraw() and .deiconify(). Maybe if you have a program that runs for long periods of time and opens a lot of windows it can be handy to avoid stackoverflow or heapoverflow.
It sure frees up the object reference from memory, but it has the additional cost of the re-instantiation, and that is processing time.
But as David J. Malan would say on CS50, “There´s always a tradeoff”.

Python: Tkinter: Multi line scrolling entry box

I would like to make a Tkinter window able to ask for a multi line entry
(so the user will add one or more lines of text)
And then when we clic on the button be able to retrieve the values entered by user for further use.
Until now I have this script:
from Tkinter import *
import ScrolledText
class EntryDemo:
def __init__(self, rootWin):
#Create a entry and button to put in the root window
self.textfield = ScrolledText(rootWin)
#Add some text:
self.textfield.delete(0,END)
self.textfield.insert(0, "Change this text!")
self.textfield.pack()
self.button = Button(rootWin, text="Click Me!", command=self.clicked)
self.button.pack()
def clicked(self):
print("Button was clicked!")
eText = self.textfield.get()
print("The Entry has the following text in it:", eText)
#Create the main root window, instantiate the object, and run the main loop
rootWin = Tk()
#app = EntryDemo( rootWin )
rootWin.mainloop()
But it didn't seem to work, A window appear with nothing inside.
Could you help me?
#########EDIT
New code:
from Tkinter import *
import ScrolledText
class EntryDemo:
def __init__(self, rootWin):
self.textfield = ScrolledText.ScrolledText(rootWin)
#Add some text:
#self.textfield.delete(0,END)
self.textfield.insert(INSERT, "Change this text!")
self.textfield.pack()
self.button = Button(rootWin, text="Click Me!", command=self.clicked)
self.button.pack()
def clicked(self):
eText = self.textfield.get(1.0, END)
print(eText)
rootWin = Tk()
app = EntryDemo( rootWin )
rootWin.mainloop()
Sorry if it look like done with no effort by some down voters (even if I spent more than a day on it) but the Multi line text entry is not exactly what we can call well documented to learn by ourself.
Your first problem is that you commented out the app = EntryDemo( rootWin ) call, so you're not actually doing anything but creating a Tk() root window, then starting its main loop.
If you fix that, your next problem is that you're trying to use the ScrolledText module as if it were a class. You need the ScrolledText.ScrolledText class.
If you fix that, your next problem is that you're trying to delete from an empty text field, which is going to raise some kind of Tcl index error, and then you're also trying to insert at position 0 in an empty text field, which will raise the same error. There's no reason to do the delete at all, and for the insert you probably want to use INSERT as the position.
You still have multiple problems after that, but fixing these three will get your edit box up and displayed so you can start debugging everything else.
A working example based on your code. Note the comment above that both the file you import and the class within the file are named "ScrolledText"
from Tkinter import *
import ScrolledText
class EntryDemo:
def __init__(self, rootWin):
#Create a entry and button to put in the root window
self.textfield = ScrolledText.ScrolledText(rootWin)
self.textfield.pack()
#Add some text:
self.textfield.delete('1.0', END)
self.textfield.insert('insert', "Change this text!")
self.button = Button(rootWin, text="Click Me!",
command=self.clicked)
self.button.pack()
def clicked(self):
print("Button was clicked!")
eText = self.textfield.get('1.0', END)
print("The Entry has the following text in it:", eText)
self.textfield.delete('1.0', END)
rootWin = Tk()
app = EntryDemo( rootWin )
rootWin.mainloop()

Simplest way to open a file in tkinter

trying to make a GUI with an 'open file' button. When I run the code shown below, the open file dialog opens straight away, and not when I press the button. Why? Is there a simple way to fix this that doesn't involve using classes? (I don't currently know anything about classes and am working on a time-pressured project)
from tkinter import *
interface = Tk()
def openfile():
return filedialog.askopenfilename()
button = ttk.Button(interface, text = "Open", command = openfile())
button.grid(column = 1, row = 1)
interface.mainloop()
The code is passing the return value of the openfile function call, not the function itself. Pass the function itself by removing trailing () which cause a call.
from tkinter import *
from tkinter import ttk
from tkinter import filedialog
interface = Tk()
def openfile():
return filedialog.askopenfilename()
button = ttk.Button(interface, text="Open", command=openfile) # <------
button.grid(column=1, row=1)
interface.mainloop()

askdirectory() changes focus to different window

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()

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