如何在GUI中并行运行两个非终止脚本？

Question

我知道我可以通过打开两个终端窗口来手动轻松地完成此操作。我试图通过创建带有两个按钮的GUI来尽可能自动化该过程。一个连接并运行监听器，另一个运行监听器。

这是我的代码：

#python 3 
#from tkinter import * 
#from tkinter import ttk 

#python 2 
from Tkinter import * 
import ttk 

import time 
import subprocess 
import paramiko 

def calculate(*args): 
    try: 
     value = float(feet.get()) 
     meters.set((0.3048 * value * 10000.0 + 0.5)/10000.0) 
    except ValueError: 
     pass 


def connect(): 
    ssh = paramiko.SSHClient() 
    ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy()) 
    ssh.connect('192.168.1.2', username='pi', password='raspberry') 
    stdin, stdout, stderr = ssh.exec_command('cd') 
    stdin, stdout, stderr = ssh.exec_command('roscore &') 
    time.sleep(20) 
    stdin, stdout, stderr = ssh.exec_command('\n') 
    stdin, stdout, stderr = ssh.exec_command('cd scripts') 
    stdin, stdout, stderr = ssh.exec_command('python /home/pi/scripts/listener2.py') 
    return 

def run(): 
    stdin, stdout, stderr = ssh.exec_command('python ES96_Vivaldi/talker2.py') 


root = Tk() 

mainframe = ttk.Frame(root, padding="3 3 12 12") 
mainframe.grid(column=0, row=0, sticky=(N, W, E, S)) 
mainframe.columnconfigure(0, weight=1) 
mainframe.rowconfigure(0, weight=1) 

ttk.Button(mainframe, text="Connect", command=connect).grid(column=1, row=3, sticky=S) 
ttk.Button(mainframe, text="Run", command=run).grid(column=3, row=3, sticky=S) 

ttk.Label(mainframe, text="Click 'Connect' to establish link.").grid(column=1, row=1, sticky=W) 
ttk.Label(mainframe, text="Click 'Run' to control using the arrow keys").grid(column=1, row=2, sticky=W) 

for child in mainframe.winfo_children(): child.grid_configure(padx=5, pady=5) 


root.mainloop() 

它打开一个小的GUI与连接按钮和一个运行按钮。连接工作正常，但由于listener2.py脚本不终止，图形用户界面冻结，我不能按运行按钮（尝试以相反的顺序时，同样的问题）。

有没有办法启动一个脚本并让它在后台运行，这样GUI不会被冻结，我可以启动下一个脚本？

谢谢！

Answer 1

您可以在后台线程中运行处理程序。在你当前的设置中，处理程序不会给gui任何反馈，所以它只是将按钮命令切换到启动线程的函数。

我添加了一些代码来禁用按钮，所以处理程序只能启动一次。这里的技巧是，你需要一些地方来存储按钮小部件，以便以后可以再次访问它们。

#python 3 
#from tkinter import * 
#from tkinter import ttk 

#python 2 
from Tkinter import * 
import ttk 

import time 
import subprocess 
import paramiko 

import threading 

# keep track of widgets for event handlers 
widget_track = {} 

# event handler creates connect thread 
def connect_evt(): 
    t = threading.Thread(target=connect) 
    t.daemon = True 
    t.start() 
    widget_track['connect'].config(text="Connected", state="disabled", command=None) 

def connect(): 
    time.sleep(5) # todo: temporary for test 
    return 
    ssh = paramiko.SSHClient() 
    ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy()) 
    ssh.connect('192.168.1.2', username='pi', password='raspberry') 
    stdin, stdout, stderr = ssh.exec_command('cd') 
    stdin, stdout, stderr = ssh.exec_command('roscore &') 
    time.sleep(20) 
    stdin, stdout, stderr = ssh.exec_command('\n') 
    stdin, stdout, stderr = ssh.exec_command('cd scripts') 
    stdin, stdout, stderr = ssh.exec_command('python /home/pi/scripts/listener2.py') 
    return 

# event handler creates run thread 
def run_evt(): 
    t = threading.Thread(target=run) 
    t.daemon = True 
    t.start() 
    widget_track['run'].config(text="Running", state="disabled", command=None) 

def run(): 
    time.sleep(5)  # todo: temporary for test 
    return 
    stdin, stdout, stderr = ssh.exec_command('python ES96_Vivaldi/talker2.py') 


root = Tk() 

mainframe = ttk.Frame(root, padding="3 3 12 12") 
mainframe.grid(column=0, row=0, sticky=(N, W, E, S)) 
mainframe.columnconfigure(0, weight=1) 
mainframe.rowconfigure(0, weight=1) 

# connect button starts connect background thread 
btn = ttk.Button(mainframe, text="Connect", command=connect_evt) 
btn.grid(column=1, row=3, sticky=S) 
widget_track['connect'] = btn 

# run button start run background thread 
btn = ttk.Button(mainframe, text="Run", command=run_evt) 
btn.grid(column=3, row=3, sticky=S) 
widget_track['run'] = btn 

ttk.Label(mainframe, text="Click 'Connect' to establish link.").grid(column=1, row=1, sticky=W) 
ttk.Label(mainframe, text="Click 'Run' to control using the arrow keys").grid(column=1, row=2, sticky=W) 

for child in mainframe.winfo_children(): child.grid_configure(padx=5, pady=5) 


root.mainloop()