This seems so simple but I can't figure out what I need to do to remedy. I have a tkinter project and on a button press, a function runs that takes several seconds. I want a "loading..." type message while the function is running so it's obvious it's actually working and not crashed. I figured a label would be easy enough and on the first line of the function, have label1.set('loading') but I suppose because of the way functions work, the label doesn't set until the function is done running--which is not helpful.
I made a second short function
def update_status(message):
label1.set(message)
and for the button in tkinter, used command=lambda:[update_status('loading'),search()] in hopes that the update_status() function would run first, alter the label, and then the second search() function that takes upwards of 30 seconds would run. But I get the same effect.
What's the simplest way finish running the update_status() function--thereby updating my label acting as the "status", and THEN run the time consuming search() function?
I'm not opposed to something more complicated like a loading window or something similar, but just wanted something simple (I have not even googled any type of loading window--I'm mostly hung up on how to get 2 functions to run on a button click in a sequential order).
Hey I do not think you need 2 functions to do what you want. You simply have to update your root so that the label is directly updated.
Here is an example:
import tkinter as tk
import time
def update_status(message1, message2):
var.set(message1)
root.update()
time.sleep(5)
var.set(message2)
if __name__ == '__main__':
root = tk.Tk()
root.title("Wait for function")
var = tk.StringVar()
var.set('Waiting for input')
label1 = tk.Label(root, textvariable=var)
label1.pack()
Button1 = tk.Button(root, text="Wait", command=lambda:update_status('loading', 'done'))
Button1.pack()
root.mainloop()
Related
script_a.py
from tkinter import *
from script_b import test
root = Tk()
var1 = stuff
var2 = stuff
def start_scriptb():
test([var1, var2])
Button(root, text="Start",
command=start_scriptb)
root.mainloop()
script_b.py
from tkinter import *
def test(x):
main = Tk()
Label(main, text=x)
Button(main, text="Exit", command=main.destroy())
main.mainloop()
This is a very basic version of what I'm trying to achieve. I actually am spawning a progress window that uses subprocess.Popen in script 2 with the passed through variables from script one and viewing the progess through a scrolled text widget on the 2nd program. I'm trying to spawn a new process, independent from the root GUI each time that button is hit from script_a.
It works fine in my tests so far, but I wanted to see if this could cause any issues or if this is actually spawning two processes?
I know there should only be one Tk() per process.
Using a TopLevel() window to show the progress works fine with the threading module, but the TopLevel() window will freeze as well as root (and any other open TopLevels()) if root is doing any sort of processing that takes any length of time.
With many hours of testing, I did have success in running two Tk() loops, but it had potential to be problematic, as "Bryan Oakley" had posted in many threads about.
Ultimately, I decided when I was in need of running something alone, I'd start my GUI with arguments and process it in an entirely new process instead of passing any arguments directly. Seems like a safer option.
I am looking for a simple way to display changing real time data in a GUI in python. I am connected to 2 devices and want to display data constantly (like 20 different values), and when I press a button I want to control the one device.
Unfortunately I fail already with the display of the data. For this I have looked at some tkinter tutorials and explanations.
My idea was to implement it with a config function and to overwrite the label continuously. As example how I wanted to display one value:
import tkinter as tk
from pydualsense import pydualsense
# connect to the device
dualsense = pydualsense()
dualsense.init()
# create a window
window = tk.Tk()
# function for updating data
def show_data():
global dualsense
data_label_output.config(text=dualsense.state.LX)
# showing the data as a lable
data_label_output = tk.Label(window)
data_label_output.grid(row=1, column=1)
show_data()
#### or different solution
# showing the data as a lable
data_label_output = tk.Label(window, comand=show_data)
data_label_output.grid(row=1, column=1)
window.mainloop()
Unfortunately, the value is displayed only once at the beginning and nothing changes after that.
Another problem:
When I press the button, I want to be able to control the one device. For this I have a while True loop that permanently checks if a button is pressed and then executes actions. As a separate program no problem, but how do I integrate this into the tkinter GUI? When I start this PyCharm always crashes.
I use PyCharm and Python 3.8
About simple and functional ideas I would be happy, also to other tools/modules etc., as long as you can easily and quickly implement the idea. It's only for a research project and the programming is only a means to an end.
You can use the after method in tkinter to run something after a short delay. The following code will run show_data once the GUI is ready and then again every 1000 milliseconds.
import tkinter as tk
from pydualsense import pydualsense
# connect to the device
dualsense = pydualsense()
dualsense.init()
# create a window
window = tk.Tk()
# function for updating data
def show_data():
global dualsense
data_label_output.config(text=dualsense.state.LX)
window.after(1000,show_data)
# showing the data as a lable
data_label_output = tk.Label(window)
data_label_output.grid(row=1, column=1)
window.after_idle(show_data)
window.mainloop()
This resolves the updating issue, I'm not sure what behaviour you want when you press the button but if you elaborate and explain, I might be able to help and update this answer.
I'm writing my first GUI program today using Tkinter and I have stumbled onto a problem. I am trying to make a game that starts with an introduction window that closes after you press a button, then opens a new window where you can choose one of two modes. Unfortunately, I just can't get it running. It looks a little something like this.
#These are the functions that I defined to make it work
def start():
root.destroy()
def Rules_mode_1():
root.destroy
rules1 = Tk()
understood1 = Button(rules1, text="I understood", command="Start_game_mode_1")
understood.pack()
rules1.mainloop
# I haven't added rules 2 yet cause I couldn't get it to work with rules 1 so I haven't even #bothered but it would be the same code just switching the 1 for a 2. But really it isn't even
#necessary to have 2 different rule functions because the rules are the same but I couldn't think
#of another way to go about it. if you have an idea let me know
def Start_game_mode_1():
rules1.destroy #<----- THIS IS WHERE THE PROBLEM LIES. JUST DOESN'T RUN
gamemode1 = Tk()
#Here I would have the game
gamemode1.mainloop()
#now same here don't have gamemode 2 yet cause it just doesn't work yet
#This is where it really starts
root = Tk()
startbutton = Button(root, text="Start", command=start)
startbutton.pack
root.mainloop
root = Tk()
def mode():
mode1 = Button(root, command=Rules_mode_1)
mode1.pack
mode2 = #Buttonblablabla
mode()
root.mainloop()
Now I've been trying around for hours, trying to give the mainloops different names. For example giving the
rules1.mainloop
#the name
root.mainloop
but that obviously didn't work. I tried it with dozens of helper function and with the lambda expression and did hours of research but just can't seem to fix it. Does anybody have any ideas? Please be respectful and keep in mind it's my first time using Tkinter.
Thank you for your help!
After the comments didn't really help me I just tried things out for hours and in case anybody ever is having a a similar problem and reads this: The rules1 variable is inside a function, and therefore only local, which means it can't be destroyed in another function. I fixed it by making it a global, like:
def Rules_mode_1():
root.destroy
global rules1
rules1 = Tk()
understood1 = Button(rules1, text="I understood", command="Start_game_mode_1")
understood.pack()
rules1.mainloop
After that I could destroy the mainloop in the next function.
My problem with my code is that I want to update my list during the delay and make the label appear twice with different values. I want b to appear first and then d will appear later. But it seems that only d is displayed now.
Is there any ways that I can go around it?
Any help is much appreciated!
import Tkinter as tk
a_list=["a","b","c"]
root=tk.Tk()
variableone=tk.StringVar()
label1=tk.Label(root,text="appear later")
label1.pack()
label=tk.Label(root, textvariable=variableone)
label.after(2000, lambda:variableone.set(a_list[1]))
label.pack()
a_list[1]="d"
label.after(5000, lambda:variableone.set(a_list[1]))
root.mainloop()
Your problem is due to your lambdas using the current value of a_list[1] when they're called, not the value it had when thelambdas were created. You can get around that by giving them a default argument, since that's only evaluated at creation time.
This is a common problem when using lambdas as callback functions. See Python Tkinter, setting up button callback functions with a loop for a similar problem using lambdas to set up a series of Button widgets in a loop.
This code does what you want. It uses s as the default argument to hold the value of a_list[1].
import Tkinter as tk
a_list=["a","b","c"]
root=tk.Tk()
variableone=tk.StringVar()
label1=tk.Label(root,text="appear later")
label1.pack()
label=tk.Label(root, textvariable=variableone)
label.after(2000, lambda s=a_list[1]:variableone.set(s))
label.pack()
a_list[1]="d"
label.after(5000, lambda s=a_list[1]:variableone.set(s))
root.mainloop()
I have created a tkinter GUI for my python script. When I run the script, I want a dynamic string in one of the Label widgets on the GUI window, which will display:
"Working."
Then:
"Working.."
then
"Working..."
and then start from "Working." again until the script is completed.
(Actually I'd prefer a progress bar in this area)
Is it possible?
I wrote two simple scripts to help demonstrate how to do what you want. The first is using the label:
import tkinter as tk
root = tk.Tk()
status = tk.Label(root, text="Working")
status.grid()
def update_status():
# Get the current message
current_status = status["text"]
# If the message is "Working...", start over with "Working"
if current_status.endswith("..."): current_status = "Working"
# If not, then just add a "." on the end
else: current_status += "."
# Update the message
status["text"] = current_status
# After 1 second, update the status
root.after(1000, update_status)
# Launch the status message after 1 millisecond (when the window is loaded)
root.after(1, update_status)
root.mainloop()
The next one is using a progressbar:
import tkinter as tk
# You will need the ttk module for this
from tkinter import ttk
def update_status(step):
# Step here is how much to increment the progressbar by.
# It is in relation to the progressbar's length.
# Since I made the length 100 and I am increasing by 10 each time,
# there will be 10 times it increases before it restarts
progress.step(step)
# You can call 'update_status' whenever you want in your script
# to increase the progressbar by whatever amount you want.
root.after(1000, lambda: update_status(10))
root = tk.Tk()
progress = ttk.Progressbar(root, length=100)
progress.pack()
progress.after(1, lambda: update_status(10))
root.mainloop()
Note however that I couldn't do too much with the progressbar script because progressbars are a little tricky and need to be customized to your script exactly. I just wrote it to maybe shed a little light on the subject. The main part of my answer though is the label script.
Yes, it is possible. There are two ways to do it:
Whenever you want to update the label from your code you can call the_widget.configure(the_text). This will change the text of the label.
You can create an instance of a tkinter.StringVar, and assign it to the textvariable attribute of a label. Whenever you change the value of the variable (via the_variable.set(the_text), the label will automatically update.
Note that for either of these to work, the event loop needs to be able to process events (ie: you won't see anything if your function takes a long time to run and you never call update_idletasks or re-enter the event loop).