Develop Reference

Trigger creation of other tkinter windows

I am trying to create a python script that will trigger a tkinter window every time a certain event happens. The python script will have a while true loop and during the loop the tkinter event may or may not happen (if-else block). Right now the actual loop part isn't done, so I am currently testing the tkinter part but I can't seem to open more than tkinter window.
Below is the test script I am using.
from tkinter import *
from sys import exit
import os
onetwo = "C:/Users/I/Downloads/Transfer_Out_1016_Outlook.txt"
def popupError(s):
popupRoot = Tk()
##popupRoot.after(20000, exit)
popupButton = Button(popupRoot, text = s, font = ("Verdana", 12), bg = "yellow", command = lambda: os.system(onetwo))
popupButton.pack()
popupRoot.geometry('400x50+700+500')
popupRoot.mainloop()
popupError("HelloWORLD")
def popupTwo(s):
popupRoot = Tk()
##popupRoot.after(20000, exit)
popupButton = Button(popupRoot, text = s, font = ("Verdana", 12), bg = "yellow", command = lambda: os.system(onetwo))
popupButton.pack()
popupRoot.geometry('400x50+700+500')
popupRoot.mainloop()
popupTwo("HEWWWWWEWEWKOO")
I apologize for the lack of an actual piece of code but this is the best I can do right now given the dev status of the other parts of the overall python script.
Note that the tkinter window may be triggered more than once in a single loop session.
If any other details are needed, I'll try my best to add more in.

Here’s what you can do:
from tkinter import *
def popup(winName):
newWin = Toplevel()
btn2 = Button(newWin, text=winName)
btn2.pack()
root = Tk()
btn = Button(root, text=“Popup”, command=lambda: popup(“text”))
btn.pack()
root.mainloop()

Continuously pass Values in Tkinter and ammend it accordingly

The purpose is that input fn takes string input and pass it into GUI fn which runs the condition and ammend tkinter window accordingly.
#*********************************** IMPORTING MODULES*****************
import tkinter
from tkinter import*
import tkinter.messagebox
import sqlite3
import os
import threading
from time import sleep
from input import*
conn = sqlite3.connect('portal.db')
c = conn.cursor()
global a
#*************** TKINTER GUI CODE******************
def gui(a):
window = tkinter.Tk()
window.title("Smart Notice Board")
#********************** FRAMES OF MAIN WINDOW(HOME)******************
top = Canvas(window,width=1024,height=184)
top.pack(fill=X)
middle = Canvas(window, width=1024, height=450, bg='steelblue')
middle.pack(fill=X)
main_left = Canvas(middle, width=275, height=450, bg='lightgreen')
main_left.pack(side=LEFT)
main_right = Canvas(middle, width=800, height=450, bg='steelblue')
main_right.pack(side=RIGHT)
bottom = Canvas(window, width=1024, height=70, bg='black')
bottom.pack(fill=X)
#************************** IMAGES********************
i_top = tkinter.PhotoImage(file='F:\\C_backup\\fyp\\5 jan 2k19\\BG.png')
top.create_image(0,10, anchor=tkinter.NW,image = i_top)
i_right = tkinter.PhotoImage(file='F:\\C_backup\\fyp\\5 jan 2k19\\aus1.png')
main_right.create_image(0,0, anchor=tkinter.NW,image = i_right)
#i_left = tkinter.PhotoImage(file='F:\\C_backup\\fyp\\5 jan 2k19\\widget1.png')
#main_left.create_image(0,0, anchor=tkinter.NW,image = i_left)
t1 = tkinter.PhotoImage(file='F:\\C_backup\\fyp\\5 jan 2k19\\first.png')
t2 = tkinter.PhotoImage(file='F:\\C_backup\\fyp\\5 jan 2k19\\BG.png')
#***************** TIMETABLE IMAGE VIEWING FN***********************
def home():
main_right.create_image(0,0, anchor=tkinter.NW,image = t2)
#*********************** TIMETABLE BUTTON PRESS FN*************************
def timetable():
main_right.create_image(0,0, anchor=tkinter.NW,image = t1)
#******************************* CONDITIONS**********************
if a == "NULL":
timetable()
if a == "HOME":
home()
#*********************** MAIN MENU BUTTONS****************
button_1 = Button(text = ' HOME', anchor = 'w', height = 2, width = 8,activebackground = '#33B5e5',bg = 'brown',fg = 'white',command = home)
top.create_window(2,150,anchor = 'nw', window = button_1)
button_2 = Button(text='TIMETABLE', height = 2, width=12, activebackground = '#33B5e5', bg = 'brown', fg = 'white',command = timetable)
top.create_window(75,150, anchor='nw', window = button_2)
window.mainloop()
#************************** MAIN LOOP************************
if __name__ == "__main__":
#print(valuea())
a=valuea()
gui(a)
Now what I want is continuously run that thing and update Tkinter window; but the 2btn fn only takes it one time and pass it into GUI fn which runs tkinter and it stucks on window.mainloop as tkinter is infinity loop.
Please suggest me a solution also u can run this code by only setting pictures from your computer

The standard method to run code regularly in the mainloop is to register a timeout function using the after method of the root window.
But, whatever you do in such a timeout function (and indeed in all other callbacks), it should not block, because that would lock up the mainloop! So you cannot use input. But you could read from sys.stdin, which is a io.TextIOWrapper instance.
You could use input in a second thread. But since Tkinter isn't thread-safe, that second thread should not use Tkinter functions or methods. So you should not simply update a label from the second thread. You could save/append the input to a global variable, but you'd have to protect that with a lock or mutex. And you'd need to use a timeout function in the main Tkinter thread to test if the lock or mutex is released by the second thread so the Tkinter thread can claim it and access the data. As you can see this is really complicated. So mixing Tkinter and threads is generally not recommended.

In order to ammend tkinter window and show the text and open picture.I did slight change in the input.py file;and coded as below
def vala():
a=speech()
if a == "HOME":
home()
if a == "NULL":
timetable()
window.after(1000,vala)
what I have done is I convert it into recursive fn that call itself after 1000ms. In this way, it can be done.
Basically, I have done it with Pocketsphinx as Input (i.e. my project takes speech input and open file/image in tkinter screen and it runs continuously)

Showing text in tkinter´s canvas repeatedly

I´m trying to use tkinter in order to show a popup window in front of all other windows that reminds me of something through a text displayed in the canvas. I want that the window pops up during some time, eg 5 seconds, and then dissapear for other time. I need this to repeat in a loop. When i tried to do it, a window appear but without the text and the specified dimensions. Here is the code:
from tkinter import *
from time import sleep as s
for i in range(5):
root = Tk()
root.lift()
root.attributes('-topmost',True)
canvas = Canvas(root,width=700,height=100)
canvas.pack()
canvas.create_text(350,50,text='Registrar rabia'+str(i),font=
('fixedsys','25'))
print('Hola')
s(1)
root.destroy()
s(1)
Also, is there a more pythonic way to do it?
EDIT:
from tkinter import *
root = Tk()
for _ in range(6):
#root.deiconify()
root.attributes('-topmost',True)
root.title("About this application...")
about_message = 'Este es el mensaje'
msg = Message(root, text=about_message)
msg.pack()
button = Button(root, text="Dismiss", command=root.withdraw)
button.pack()
root.after(1000)
It didn´t work. I need only one message and one button, and in the code above,
python shows 6 messages and 6 buttons... Also i need to put a delay between appearances but i can´t understand how to use the after method in this particular case.

Trying to print the output from my function inside my GUI window

Im trying to make a little program that endlessly prints out numbers inside GUI window, I can not find a way to print the out put of the function in a text box inside the GUI window instead of the python shell, please help, here is my code so far...
import sys
from tkinter import *
root = Tk()
def number(event):
x = 420
while True:
x +=420
print(x^70)
button_1 = Button(root, text="Start...")
button_1.bind("<Button-1>", number)
button_1.pack()
root.mainloop()
Thanks Harvey

You'll find it hard to constantly insert a value into a widget. The widget does not update with each insert. You can think of it has having a temporary variable for it. It can be accessed during the loop (as shown with print). However you'll notice that the widget itself doesn't update until the loop is over. So if you have while True then your widget will never update, and so you won't have the numbers streaming into the widget.
import sys
from tkinter import *
root = Tk()
def number():
x = 420
while x < 8400: # Limit for example
x +=420
textbox.insert(END, str(x^70)+'\n')
print(textbox.get(1.0, END)) # Print current contents
button_1 = Button(root, text="Start...", command=number) #Changed bind to command, bind is not really needed with a button
button_1.pack()
textbox = Text(root)
textbox.pack()
root.mainloop()

Destroying Toplevel window doesn't let the application come out of the main loop

I am new to Tkinter. I am trying to destroy the Toplevel window and it gets destroyed perfectly but nothing's running after that. The cursor just keeps on blinking in python shell as it happens while running an infinite loop.
Here's my code :
def error_msg(msg) :
root1 = Tk.Toplevel()
root1.attributes("-topmost", True)
root1.title("Error")
w1 = 230
h1 = 100
ws1 = root1.winfo_screenwidth()
hs1 = root1.winfo_screenheight()
x1 = (ws1/2) - (w1/2)
y1 = (hs1/2) - (h1/2)
root1.geometry('%dx%d+%d+%d' % (w1, h1, x1, y1))
can1 = Tk.Canvas(root1,width = 230,height=100)
can1.pack()
im1 = Image.open("img.png")
tkimage1 = ImageTk.PhotoImage(im1)
Canvas_Image1 = can1.create_image(0,0, image=tkimage, anchor="nw")
canvas_id1 = can1.create_text(15, 10, anchor="nw")
can1.itemconfig(canvas_id1, text=msg)
Tk.Button(root1, text='OK', command =root1.destroy).place(x=110,y=70)
root1.mainloop()
root1.quit()
print 'lol'
return None
error_msg("This is an error")
print 'Help'
Before this I have already a Tk() window open so I am using a Toplevel() window.
On running I am getting a window which opens and shows the message. I click on ok and everything just halts. 'lol' does not print in the shell and function never ends (as return statement is not reached), hence 'Help' is also not printed
Any Idea why is this happening ??
Thanks,

For a dialog window, instead of creating a new mainloop, you should use wait_window(). This waits until the Toplevel window is closed and then continues execution of the following lines.
So you should replace
root1.mainloop()
root1.quit()
with
root1.wait_window()
For more tips on creating a dialog window see this article on effbot.org.