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python tkinter: Calling a objects method on button click does not work

here is my sample code:
from time import sleep
import tkinter as tk
import threading
class Action:
counter = 0
def do_something(self):
while True:
print('Looping')
sleep(5)
action = Action()
root = tk.Tk()
button = tk.Button(root, text='pressme harder', command=threading.Thread(target=action.do_something()).start())
button.grid(row=1, column=0)
root.mainloop()
What am I expecting?
I'm expecting that as soon as I click the button in the UI an new thread is running, which is looping in the background and does not interfere with the UI (or later maybe other threads doing tasks in the background)
What is really happening?
When running the code, the method of the class is executeds immdiately and locking the procedure. root.mainloop() is never reached and therefore no UI is drawn
Alternatively I tried the following change:
button = tk.Button(root, text='pressme harder', command=threading.Thread(target=lambda: action.do_something()).start())
This behaves in the following (imho wrong) way:
The method is also called immediately, without pressing the button. This time the UI is drawn but seems the be locked by the thread (UI is slow/stuttering, pressing the buttom does not work most of the time)
Any Idea whats wrong there? Or how do I handle this in a more stable way?

You shouldn't try to start a thread directly in the button command. I suggest you create another function that launches the thread.
from time import sleep
import tkinter as tk
import threading
class Action:
counter = 0
def do_something(self):
while True:
print('Looping')
sleep(2)
print("Finished looping")
def start_thread(self):
thread = threading.Thread(target=self.do_something, daemon=True)
thread.start()
action = Action()
root = tk.Tk()
button = tk.Button(root, text='pressme harder', command=action.start_thread)
button.grid(row=1, column=0)
root.mainloop()

How to create a non blocking Python tkinter window [duplicate]

This question already has answers here:
Tkinter: How to use threads to preventing main event loop from "freezing"
(5 answers)
Closed 4 years ago.
I wanted to create a non-blocking message window with Tkinter. This in order to display a wait message, when another function is waiting for a reply. Once the reply is received the window can be closed automatically. I managed to find some info on the web and I made the following:
import tkinter as tk
import threading
import time
class Show_Azure_Message(threading.Thread):
def __init__(self, message):
self.thread = threading.Thread.__init__(self)
self.message = message
self.start()
#staticmethod
def callback():
return
def destroy(self):
self.root.quit()
#run will be called from self.start()
def run(self):
self.root = tk.Tk()
self.root.protocol("WM_DELETE_WINDOW", self.callback)
self.t2 = tk.Text(self.root, height=10, borderwidth=0, wrap=tk.WORD)
self.t2.insert(1.0, self.message)
self.t2.grid(padx=5,row=2)
self.t2.config(state=tk.DISABLED)
self.root.mainloop()
App = Show_Azure_Message('Hello')
for i in range(0,2):
print(i)
time.sleep(1)
App.destroy()
This runs fine when I execute this as main script, but when I want to run another gui application with Tkinter right after i get the following error
RuntimeError: main thread is not in main loop
Also when I run another piece of code after the App.destroy(). Then the App window doesn't close end the application keeps running.
root = tk.Tk()
label = tk.Label(root, text='Hello2')
label.pack()
root.mainloop()
So probably I am doing something wrong but I cannot find out what the problem is. Next to that I don't have much experience with Python Threads hence maybe I am missing something trivial over here.
regards,
Geert

I think, if you really want to do it that way (look in the comment section of your post) you should use a Toplevel window instead since they don't need a mainloop which is making things way more easy in my eyes.
That's some kind of how I would do it if I would have to:
from tkinter import *
import threading
import time
class Show_Azure_Message(Toplevel):
def __init__(self,master,message):
Toplevel.__init__(self,master) #master have to be Toplevel, Tk or subclass of Tk/Toplevel
self.title('')
self.attributes('WM_DELETE_WINDOW',self.callback)
self.resizable(False,False)
Label(self,text=message,font='-size 25').pack(fill=BOTH,expand=True)
self.geometry('250x50+%i+%i'%((self.winfo_screenwidth()-250)//2,(self.winfo_screenheight()-50)//2))
def callback(self): pass
BasicApp=Tk()
App = Show_Azure_Message(BasicApp,'Hello')
for i in range(0,2):
print(i)
time.sleep(1)
App.destroy()

cant open one tk window per thread , tkinter

I want to write a program which every time accept a message pop-up a window at the corner of the desktop.
I use the web server to accept message.
And my Tk code is like this:
import threading
from Tkinter import *
import time
def alert():
alert = Tk()
alert.protocol("WM_DELETE_WINDOW", alert.quit)
alert.mainloop()
def run():
th = threading.Thread(target=alert)
th.start()
if __name__ == 'main':
run()
time.sleep(5)
run()
time.sleep(5)
run()
When I ran this, only one window pop-up. It seems that the program hang-up when the second thread went 'alert = Tk()', I'm not sure.
The third thread never ran.
If I didn't close the window before the second thread started, the window would be out of response.
I want to know what's wrong with my code and how tkinter works.
Thanks

Stopping a python thread from a tkinter gui

I'm trying to create a simple Python GUI (with Tkinter) with start button, running a while loop in a thread, and a stop button to stop the while loop.
I'm having issue with the stop button, which doesn't stop anything and frozen GUI once the start button is clicked.
See code below:
import threading
import Tkinter
class MyJob(threading.Thread):
def __init__(self):
super(MyJob, self).__init__()
self._stop = threading.Event()
def stop(self):
self._stop.set()
def run(self):
while not self._stop.isSet():
print "-"
if __name__ == "__main__":
top = Tkinter.Tk()
myJob = MyJob()
def startCallBack():
myJob.run()
start_button = Tkinter.Button(top,text="start", command=startCallBack)
start_button.pack()
def stopCallBack():
myJob.stop()
stop_button = Tkinter.Button(top,text="stop", command=stopCallBack)
stop_button.pack()
top.mainloop()
Any idea how to solve this? I'm sure this is trivial and must have be done thousands of times but I cannot find a solution myself.
Thanks
David

The code is calling run method directly. It will call the method in the main thread. To run it in a separated thread you should use threading.Thread.start method.
def startCallBack():
myJob.start()

Infinite loop in Tkinter python code

I'm trying to run a simple Tkinter program that opens a program when you click a button. The code is listed below. I use a command to call a program that then calls a fortran program. However, when I click on the button, it opens the program but the menu of the program i'm calling goes into an infinite loop......the offending code seems to be in the button1Click module.
Any help is greatly appreciated.
Thanks
from Tkinter import *
import os, sys
from win32com.client import Dispatch
xlApp=Dispatch('Excel.Application')
_PSSBINPATH=r"C:\Program Files\PTI\PSSE32\PSSBIN"
os.environ['PATH']=_PSSBINPATH+';'+os.environ['PATH']
sys.path.insert(0,_PSSBINPATH)
import redirect; redirect.psse2py()
import psspy
class MyApp:
def __init__(self, parent):
self.myParent = parent ### (7) remember my parent, the root
self.myContainer1 = Frame(parent)
self.myContainer1.pack()
self.button1 = Button(self.myContainer1)
self.button1.configure(text="OK", background= "green")
self.button1.pack(side=LEFT)
self.button1.bind("<Button-1>", self.button1Click) ### (1)
self.button2 = Button(self.myContainer1)
self.button2.configure(text="Cancel", background="red")
self.button2.pack(side=RIGHT)
self.button2.bind("<Button-1>", self.button2Click) ### (2)
def button1Click(self,event): ### (3)
psspy.runiplanfile(r"C:\MNTACT\Contingency Program\work\contingency-31-4.irf")
if self.button1["background"] == "green": ### (4)
self.button1["background"] = "yellow"
else:
self.button1["background"] = "green"
def button2Click(self, event): ### (5)
self.myParent.destroy() ### (6)
root = Tk()
myapp = MyApp(root)
root.mainloop()

What makes you think there's an infinite loop happening? I see no loop in button1Click, unless the loop is in runiplanfile. Are you using "infinite loop" to mean simply that the GUI has stopped responding?
Tkinter is single threaded and cannot process events except via the event loop. If one event takes a long time to process, the GUI will hang until the processing of that event is completed. If you're exec'ing an external process and waiting for it to complete, your GUI will appear to be frozen until that process finishes.