Python tkinter 维护 gui 并从 pipe 读取

Question

I am trying to achieve reading from subprocess pipe stdout and stderr and updating GUI simultaneously. However my code is waiting all pipe reading process then updates all.

import tkinter as tk
from tkinter.filedialog import askopenfilename, asksaveasfilename
import subprocess
import threading
import time
from queue import *

class Application:
    
    # load main window of application
    def __init__(self, master):
        self.current_script_file_name = None
        self.q = Queue()

        self.window = master
        self.window.title("TK")
        self.window.rowconfigure(1, minsize = 600, weight = 2)
        self.window.columnconfigure(1, minsize = 600, weight= 2)

        # create frame for buttons and create buttons
        self.frame_buttons = tk.Frame(master = self.window, relief = tk.RAISED, bd = 2)
        self.button_save = tk.Button(master = self.frame_buttons, text = "Save", command = self.save_script_to_file)
        self.button_run = tk.Button(master = self.frame_buttons, text = "Run", command = self.run_script_from_file)

        # create frame for tk.Text editor and output
        self.frame_text = tk.Frame(master = self.window, relief = tk.RAISED, bd = 2)
        self.text_editor = tk.Text(self.frame_text)
        self.text_output = tk.Text(self.frame_text, background = "Black", foreground = "White")

        #adjust buttons
        self.button_save.grid(row = 0, column = 0, sticky = "ew", padx = 5, pady = 5)
        self.button_run.grid(row = 1, column = 0, sticky = "ew", padx = 5)
        self.frame_buttons.grid(row = 0, column = 0, sticky = "ns")

        #adjust text editor and text output
        self.text_editor.grid(row = 0, column = 0, sticky = "ew", padx = 10, pady = 10)
        self.text_output.grid(row = 1, column = 0, sticky = "ew", padx = 5, pady = 5)
        self.frame_text.grid(row = 0, column = 1, sticky = "ns")

        self.text_output.insert(tk.END, 'Script Result:\n')
        
    def run(self):
        self.window.mainloop()

    def save_script_to_file(self):
        file_path = asksaveasfilename(
            filetypes=[("Python Scripts", "*.py"), ("Kotlin Scripts", "*.kts*")]
        )
        if not file_path:
            return
        with open(file_path, "w") as output_file:
            text = self.text_editor.get(1.0, tk.END)
            output_file.write("#!/usr/bin/env python3\n")
            output_file.write(text)
            
        self.window.title(f"Text Editor Application - {file_path}")


    def run_script_from_file(self):
        # start thread so main window not going to freeze
        threading.Thread(target=self.run_script).start()
        self.update()



    def run_script(self):
        sub_proc = subprocess.Popen(['python','script.py'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)

        threading.Thread(target=self.pipe_reader, args=[sub_proc.stdout]).start()
        threading.Thread(target=self.pipe_reader, args=[sub_proc.stderr]).start()

    def update(self):
        while not self.q.empty():
            for source, line in iter(self.q.get, None):
                self.text_output.insert(tk.END,line)
        self.window.after(1000,self.update)


    def pipe_reader(self, pipe):
        try:
            with pipe:
                for line in iter(pipe.readline, b''):
                    self.q.put((pipe, line))
        finally:
            self.q.put(None)

if __name__ == '__main__':
    root = tk.Tk()
    app = Application(root)
    app.run()

run_script_from_file is a button command. And self.q is a Queue belongs to same class of this functions.

Why my text_output tk.Text field is not updating asap

Script.py:

#!/usr/bin/env python3

import time

counter = 1
while counter < 6:
    print ("The current counter value: %d" % counter)
    counter = counter + 1
    time.sleep(1)


print(asd)

Edit: I put all my code Edit: Added script.py

Answer 1

Ok, so this is actually not too far off. One common gotcha, due to buffering you have to run python in -u mode. Only other thing really is to have the tkinter update loop running all the time. Try this:

import tkinter as tk
from tkinter.filedialog import askopenfilename, asksaveasfilename
import subprocess
import threading
import time
from queue import *

class Application:

    # load main window of application
    def __init__(self, master):
        self.current_script_file_name = None
        self.q = Queue()

        self.window = master
        self.window.title("TK")
        self.window.rowconfigure(1, minsize = 600, weight = 2)
        self.window.columnconfigure(1, minsize = 600, weight= 2)

        # create frame for buttons and create buttons
        self.frame_buttons = tk.Frame(master = self.window, relief = tk.RAISED, bd = 2)
        self.button_save = tk.Button(master = self.frame_buttons, text = "Save", command = self.save_script_to_file)
        self.button_run = tk.Button(master = self.frame_buttons, text = "Run", command = self.run_script_from_file)

        # create frame for tk.Text editor and output
        self.frame_text = tk.Frame(master = self.window, relief = tk.RAISED, bd = 2)
        self.text_editor = tk.Text(self.frame_text)
        self.text_output = tk.Text(self.frame_text, background = "Black", foreground = "White")

        #adjust buttons
        self.button_save.grid(row = 0, column = 0, sticky = "ew", padx = 5, pady = 5)
        self.button_run.grid(row = 1, column = 0, sticky = "ew", padx = 5)
        self.frame_buttons.grid(row = 0, column = 0, sticky = "ns")

        #adjust text editor and text output
        self.text_editor.grid(row = 0, column = 0, sticky = "ew", padx = 10, pady = 10)
        self.text_output.grid(row = 1, column = 0, sticky = "ew", padx = 5, pady = 5)
        self.frame_text.grid(row = 0, column = 1, sticky = "ns")

        self.text_output.insert(tk.END, 'Script Result:\n')

        self.update()

    def save_script_to_file(self):
        file_path = asksaveasfilename(
            filetypes=[("Python Scripts", "*.py"), ("Kotlin Scripts", "*.kts*")]
        )
        if not file_path:
            return
        with open(file_path, "w") as output_file:
            text = self.text_editor.get(1.0, tk.END)
            output_file.write("#!/usr/bin/env python3\n")
            output_file.write(text)

        self.window.title(f"Text Editor Application - {file_path}")

    def run_script_from_file(self):
        sub_proc = subprocess.Popen(['python3', '-u','script.py'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        threading.Thread(target=self.pipe_reader, args=[sub_proc.stdout]).start()
        threading.Thread(target=self.pipe_reader, args=[sub_proc.stderr]).start()

    def update(self):
        while not self.q.empty():
            source, line = self.q.get()
            if line is None:
                line = "DONE"
            self.text_output.insert(tk.END,line)
        self.window.after(100, self.update)

    def pipe_reader(self, pipe):
        for line in iter(pipe.readline, b''):
            self.q.put((pipe, line))
        self.q.put((pipe, None))

if __name__ == '__main__':
    root = tk.Tk()
    app = Application(root)
    root.mainloop()