I would like to display some numbers, as fast as possible in Tkinter. The Program, I am trying to do, gets many numbers send and should show those.
Here is an similar environment, where tinter has to change a label very quickly.
from tkinter import *
import time
window = Tk()
lbl13 = Label(window, text="-")
lbl13.grid(column=0, row=0)
x = 0
while 1:
lbl13.config(text = str(x))
time.sleep(2)
x +=1
window.mainloop()
The Tkinter window doesn't even open on my computer. Is that because i have too weak hardware? What could I change that this Program also runs on my Computer. Thank you for every answer!
The infinite while loop will keep the program from getting to the line where you call window.mainloop(). You should call window.update() repeatedly instead of window.mainloop() at the end:
from tkinter import *
import time
window = Tk()
lbl13 = Label(window, text="-")
lbl13.grid(column=0, row=0)
x = 0
while 1:
lbl13.config(text = str(x))
window.update()
x +=1
Using after and a proper mainloop is probably a more more flexible way to achieve what you want; it is also reusable in different contexts, and can be used in an application that does more than trivially increment a number on a label:
maybe something like this:
import tkinter as tk
if __name__ == '__main__':
def increment():
var.set(var.get() + 1)
label.after(1, increment)
window = tk.Tk()
var = tk.IntVar(0)
label = tk.Label(window, textvariable=var)
label.pack()
increment()
window.mainloop()
Related
So my aim is to use a single function to show a text message upon a button click. Then there should be a delay and then another text message should be displayed.
The game is a dice game that should show 'Rolling...' upon a button click. And then after a while, it should display a random number.
I tried both .sleep() and .after() and both of them resulted in my program not showing the before delay text. Here's my code:
# Imports
import tkinter as tk
from random import randrange
import time
# Global variables
# SIDES is a constant
SIDES = 12
# Functions
def func():
display["text"] = "Rolling..."
window.after(2000)
display["text"] = str(randrange(SIDES) + 1)
# Main program loop
window = tk.Tk()
display = tk.Label(window, text="Press the button \nto roll the dice.", width=20, height=3)
button = tk.Button(window, text="Roll", command=func)
display.pack()
button.pack(pady=10)
window.mainloop()
Any help would be much appreciated!
Try:
window.after(2000, lambda: display.config(text=randrange(SIDES) + 1))
instead of the:
window.after(2000)
display["text"] = str(randrange(SIDES) + 1)
The problem is that when you sleep in the function, the tkinter main loop is interrupted and the screen isn't updated. (window.after() is just a gloified sleep here). The correct solution is to pass a callback to after, which will make it immediately return and call the callback later:
def func():
display["text"] = "Rolling..."
window.after(2000, lambda: display.__setitem__("text", str(randrange(SIDES) + 1)))
(Note that the call to __setitem__ is a direct one-liner lambda translation. This is not good design.)
I would like to implement a very simple GUI for my project. I was previously using just Print statements to output some text and data. However, that is not very conveneint and since a person will need to operate a device that I am coding, he needs to be clearly see the instructions that I am going to display on GUI.
my code:
main()
myConnection = mysql.connector.connect( host=hostname, user=username, passwd=password, db=database )
counter = 0
window = tk.Tk()
window.title("GUI")
window.geometry("400x200")
while(1):
# OPERACIJOS KODAI:
# 0 - PILDYMAS
# 1 - KOMPLEKTAVIMAS
# 2 - NETINKAMAS KODAS
tk.Label(window,text = "Scan barcode here:").pack()
entry = tk.Entry(window)
entry.pack()
var = tk.IntVar()
button = tk.Button(window,text="Continue",command = lambda: var.set(1))
button.pack()
print("waiting...")
button.wait_variable(var)
result = entry.get()
print("Entry string=",result)
var.set(0)
operacijos_kodas=Scanning_operation(myConnection,result)
print("operacijos kodas=",operacijos_kodas)
if(operacijos_kodas == 0):
tk.label(window,text = "PILDYMO OPERACIJA:").pack()
pildymo_operacija(myConnection)
elif(operacijos_kodas == 1):
tk.Label(window,text = "PAKAVIMO OPERACIJA:").pack()
insertData_komplektacija(myConnection,"fmb110bbv801.csv");
update_current_operation(myConnection);
picking_operation();
elif(operacijos_kodas == 2):
print("Skenuokite dar karta")
#break
window.mainloop();
Nothing is being displayed. It just opens up an empty GUI window.
First of all, I am unsure where should I call function window.mainloop().
Secondly, since my system runs in an infinite while loop ( the operation starts when a user scans a bar-code, then he completes an operation and the while loop starts over again (waiting for user to scan a bar-code). So I just simply have to display some text and allow user to input data in the text box.
Could someone suggest me whether this GUI is suitable for my needs or I should look for an alternatives?
UPDATE*********************
I have tried to use mainloop:
print ("Using mysql.connector…")
main()
GPIO_SETUP()
myConnection = mysql.connector.connect( host=hostname, user=username, passwd=password, db=database )
counter = 0
window = tk.Tk()
window.resizable(False,False)
window_height = 1000
window_width = 1200
#window.attributes('-fullscreen',True)
#window.config(height=500,width=500)
#can = Canvas(window,bg='red',height=100,width=100)
#can.place(relx=0.5,rely=0.5,anchor='center')
window.title("GUI")
screen_width = window.winfo_screenwidth()
screen_height= window.winfo_screenheight()
x = int((screen_width/ 2) - (window_width / 2))
y = int((screen_height/ 2) - (window_height / 2))
window.geometry("{}x{}+{}+{}".format(window_width,window_height,x,y))
label1=Label(window,text = "SKENUOKITE BARKODA(GUID) ARBA DAIKTO RIVILINI KODA:")
label1.pack()
entry = Entry(window)
entry.pack()
var = tk.IntVar()
button = Button(window,text="Testi operacija",width = 30,command = lambda: var.set(1))
button.pack()
#button2 = Button(window,text="RESTARTUOTI SISTEMA",width = 30,command = restart_devices())
#button2.pack()
print("waiting...")
button.wait_variable(var)
Scanned_serial = entry.get()
print("Entry string=",Scanned_serial)
var.set(0)
label2=Label(window,text = "Vykdoma operacija:")
label2.pack()
window.update()
window.after(1000,Full_operation(Scanned_serial,label2,window))
window.mainloop()
This is my code. As you can see. i call Full_operation function and then window.mainloop()
my Full_operation:
def Full_operation(Scanned_serial,label2,window):
operacijos_kodas=Scanning_operation(myConnection,Scanned_serial)
print("operacijos kodas=",operacijos_kodas)
if(operacijos_kodas == 0):
label2.config(text = "SPAUSKITE MYGTUKA ANT DEZES KURIA NORITE PILDYTI:")#update the label2
window.update()#call update to update the label
pildymo_operacija(myConnection,Scanned_serial,label2,window)
elif(operacijos_kodas == 1):
insertData_komplektacija(myConnection,"fmb110bbv801.csv");
update_current_operation(myConnection);
#label2.config(text = "IMKITE DAIKTUS IS ZALIOS DEZUTES:")#update the label2
picking_operation(myConnection,label2);
elif(operacijos_kodas == 2):
print("Skenuokite dar karta")
label2.config(text = "NUSKENUOTAS NEGALIMAS KODAS:")#update the label2
window.update()#call update to update the label
How can I ensure that everytime I enter FUll_operation function I start from clean GUI again and start another operation.
Now I am able to complete operation once. After that, the GUI is not responsive.
I have added a print statement at the beggining of my full_operation and it does not execute after I complete it once so my mainwindow does not seem to work properly.
You'll need to adapt your code to work with a GUI. You can't introduce infinite loops in to tkinter GUI's without causing all sorts of problems.
Mainloop should only be called once.
I'd suggest that you move all of your scanning/saving operations in to a separate function which you schedule to occur periodically using the tkinter after method.
For example if you call your function scan you would schedule it to occur after 1 second using
root.after(1000, scan)
A more advanced method would be to have your scanning code running on a separate thread.
Also, you are currently trying to create the label each time you go round the while loop rather than just creating and packing them once and updating the text of the labels when you perform the "scanning". You can update the text of a label using the config method, for example
## Create a label
label1 = tk.Label(window,text = "PAKAVIMO OPERACIJA:")
##Pack the label
label1.pack()
## Update the text later
label1.config(text="New Text")
Here is an example of updating tkinter widgets periodically from a function.
import tkinter as tk
import random
def scanning():
num = random.randint(0,100)
entryTemperature.delete(0, tk.END) #Delete the current contents
entryTemperature.insert(0, f"{num} K") #Add new text
root.after(1000, scanning) #Schedule the function to run again in 1000ms (1 second)
root = tk.Tk()
entryTemperature = tk.Entry(root)
entryTemperature.grid(padx=50,pady=50)
root.after(1000, scanning)
root.mainloop()
I am new to python and I have been learning tkinter recently. So I thought with myself that using the grid_forget() function I can remove a widget and redefine it. I thought of this animation that changes the padding of a label so it would create space (kind of like moving the label but not exactly). However, the animation does not work at all. The program freezes until the label reaches the last value of the padding. How can I fix this? Or is there a better way to animate a label moving in the screen?
Here is my code:
from tkinter import *
import time
root = Tk()
lbl = Label(root, text='------')
lbl.grid(row=0, column=0)
def animation():
padding = 0
while padding < 31:
lbl.grid_forget()
padding += 1
lbl.grid(row=0, column=0, padx=padding)
time.sleep(0.2)
# alternative: root.after(200, lambda: lbl.grid(row=0, column=0, padx=padding))
btn = Button(root, text='Animate', command=animation)
btn.grid(row=1, column=1)
root.mainloop()
You need to update the screen for changes to be shown.
Here is a working version using the .update() method:
from tkinter import *
import time
root = Tk()
lbl = Label(root, text='------')
lbl.grid(row=0, column=0)
def animation():
padding = 0
while padding < 31:
lbl.grid_forget()
padding += 1
lbl.grid(row=0, column=0, padx=padding)
root.update()
time.sleep(0.2)
# alternative: root.after(200, lambda: lbl.grid(row=0, column=0, padx=padding))
btn = Button(root, text='Animate', command=animation)
btn.grid(row=1, column=1)
root.mainloop()
Here is a way I also use to animate stuff on the screen, I am not able to understand what you were trying to achieve with your code snippet above, I tried making some changes to it but I feel this way is much better and let's you get more control of your window.
This uses the widely used Canvas widget in the tkinter library.
The Canvas is a general purpose widget, You can use it for a lot of things. Visit the hyper link for more clarity
Here is a short example of how you would create text on the screen.
from tkinter import *
root = Tk()
root.title("My animation")
c = Canvas(root)
x = 20
y = 20 #Instead of using row and column, you simply use x and y co-ordinates
#We will use these co-ordinates to show where the text is in the starting
my_text = c.create_text(x,y,text = '-----')
c.pack()
# This is all you need to create this text on your screen!
root.mainloop()
The idea is that you put your canvas up on your window , and then place whatever you want on it.
There are a lot more attributes that you can add to make your text look even better. Here is an in-depth tutorial on it.
Now that we have made your text widget, It is now time to move it around. Let us move it to 90,20 From our initial position which is 20,20
Here is how we will do it. If we simply move to text object to 90,90, We won't see any animations, it will just directly have it there. So what we will do is first create it at 21,20. Then 22,20. And so on...
We do this really fast till we reach 90,20
This looks like we are moving the text
from tkinter import *
import time
root = Tk()
root.title("My animation")
c = Canvas(root)
x = 20
y = 20 #Instead of using row and column, you simply use x and y co-ordinates
#We will use these co-ordinates to show where the text is in the starting
my_text = c.create_text(x,y,text = 'weee')
c.pack()
def animation():
y = 0.1
x = 0
for _ in range(1000):
c.move(my_text,x,y)
root.update()
anlabel = Button(root,text = 'Animate!',command = animation).pack()
root.mainloop()
This is not only applicable to text, but everything (like other images)that is there on the canvas. The canvas also has Events which will let you use mouse-clicks and other keys on the computer too.
I have made some changes from the previous code, But it is executable and you can try it for yourself to see how it works. increasing the value in time.sleep() makes the animation slower, the lesser the value, the faster.
Are you sure you aren't trying to do something more like the below example? Animating the padding on one of your widgets is going to screw up the rest of your display.
from tkinter import *
import time
root = Tk()
lbl = Label(root, text='')
lbl.grid(row=0, column=0)
def animation(step=12):
step = 12 if step < 0 else step
lbl['text'] = ' ------ '[step:step+6]
root.after(200, lambda: animation(step-1))
Button(root, text='Animate', command=animation).grid(row=1, column=0, sticky='w')
root.mainloop()
I am new to Tkinter. I was experimenting with this, but while the Tkinter starts just fine, it some times freezes after a while for no reason. Actually, the weird thing that happens, is that while the Tkinter windows do not update the information anymore, the counter keeps printing ON MY WINDOWS DESKTOP LEFT TOP SIDE! (just the black bg box with the white font that shows the counter number) and eventually finds number 777 and ends. But long freezes in between, even without any printing (not on my Windows desktop either)
this is the normal tkinter window
this is the console output
all good here
crazy Windows display here
The simple program here is generating random ints from 1 - 10000 and should 1) if 777 is found it should print the counter and exit 2) if any number between 1-100 is found, it should print the number and counter.
I am trying to learn how to print new content in the same line, and if something happens print more info on another line, while the first (or more) keep updating.
I'm not sure if I exit the program the right way or how exactly I should be using/calling the Tkinter function to update the info on the screen.
Any help or tips most appreciated.
from tkinter import *
import random
import time
tk=Tk()
i = 0
counter = 0
tk.title("Testing...")
tk.geometry('300x200')
canvas_width = 200
canvas_height = 100
canvas = Canvas(tk, width=canvas_width, height=canvas_height, bg='white')
canvas.pack(expand=YES)
def screen(Found):
#canvas.create_text(20, 20, text="Counter:" + str(counter), font="Times 20 italic")
widget = Label(canvas, text="Counter:" + str(counter), fg='white', bg='black')
widget.grid(column=0, row=0)
if Found:
widget = Label(canvas, text="Number " + str(i) +" was found at counter:" + str(counter), fg='white', bg='black')
widget.grid(column=0, row=1)
found = False
loop = True
while loop:
counter += 1
i = random.randint(1, 10000)
if i in range(1, 100):
print("Found i = ", i, " in counter:", counter)
Found = True
else:
Found = False
if i == 777:
loop = False
print("JUST FOUND 777")
print("Counter:", counter)
screen(Found)
tk.update_idletasks()
tk.update()
# tk.mainloop()
As a matter of design, it is usually a better approach to rely on the tkinter mainloop to drive the application. root.after is a great substitute to a while loop. Labels do not need to be recreated; they can use special variables that update the displayed values themselves, and their properties can be reconfigured. Calling update, and update_idletasks is hardly ever needed.
The following is maybe a better approach where one single label is updated from a loop powered by the tkinter mainloop:
(it shows you "how to keep displaying new stuff, without such label issues")
import tkinter as tk
import random
def screen(found, v, c):
if found:
label.configure(bg='red', fg='blue')
print('found')
else:
label.configure(bg='black', fg='white')
update_lbl_txt(v, c)
def update_lbl_txt(v=0, c=0):
txt = f'Number at {v} was found at counter {c}'
lbl_txt.set(txt)
def found_target(t):
return t in range(1, 100) or t == 777
def loop(c=0):
v = random.randint(1, 10000)
screen(found_target(v), v, c)
root.after(100, loop, c+1)
root = tk.Tk()
root.title("Testing...")
root.geometry('300x200')
lbl_txt = tk.StringVar(root)
update_lbl_txt()
label = tk.Label(root, textvariable=lbl_txt, fg='white', bg='black')
label.pack(expand=True, fill=tk.BOTH)
loop()
root.mainloop()
The reason it seems to freeze it at least partly because you have an infinite loop that you never, ever break out of. Most of the time i will not be in the range of 1 to 100, nor will it be 777, but your loop will keep on running and never update the screen.
You're also creating hundreds or thousands of label widgets every second, stacked on top of one another. You will run into performance issues rather quickly.
from tkinter import *
from random import *
root = Tk()
#A function to create the turn for the current player. The current player isnt in this code as it is not important
def turn():
window = Tk()
dice = Button(window, text="Roll the dice!", bg= "white", command=lambda:diceAction(window))
dice.pack()
window.mainloop()
#a function to simulate a dice. It kills the function turn.
def diceAction(window):
result = Tk()
y = randint(1, 6)
quitButton = Button(result, text="Ok!", bg="white", command=result.destroy)
quitButton.pack()
window.destroy()
result.mainloop()
#A function to create the playing field and to start the game
def main():
label1 = Button(root, text="hi", bg="black")
label1.pack()
while 1:
turn()
print("Hi")
turn()
main()
root.mainloop()
My problem is that the code in the while function after the first turn() the code isnt executed until i close the root window(which i dont want because it represents the playing field). You can copy this code and execute it yourself if you want.
I have no idea what causes this and havent found anything online. Sorry for the long code but i wrote it so that it is executeable.
I don't know why this particular problem is occurring, but there are a couple of things in your code that are considered bad practice.
Instead of creating multiple instances of Tk(), you should use Toplevel widgets for any pop-up windows needed. Also, it's better to use root.mainloop() to run the program rather than a while loop.
I've made some edits to your code so that it uses a Toplevel widget and discards of the while loop.
from tkinter import *
from random import *
#A function to create the turn for the current player. The current player isnt in this code as it is not important
def turn(prev=None):
# destroy the previous turn
if prev:
prev.destroy()
# pop up with dice
window = Toplevel()
dice = Button(window, text="Roll the dice!", bg= "white")
dice.config(command=lambda b=dice, w=window:diceAction(b, w))
dice.pack()
#a function to simulate a dice, reconfigures the pop-up
def diceAction(button, window):
# roll dice
y = randint(1, 6)
# use dice result here?
print(y)
# reconfigure button, the command now starts a new turn
button.config(text='ok', command=lambda w=window:turn(prev=w))
root = Tk()
# I hijacked this button to use as a start button
label1 = Button(root, text="hi", bg="black", command=turn)
label1.pack()
root.mainloop()
I don't know if this is what you need, but it functions as the code in the question would if it worked.
Sorry I couldn't help with the cause of the error.