如何在python中刷新文本

Question

我在Gnu/Linux上有一个python应用程序。该程序从内核启用或禁用摄像头和麦克风。这个程序运行良好，除了一个我无法解决的小问题。该程序有4个按钮。有两个按钮可以启用相机和麦克风，还有两个按钮可禁用它们。共有四个文本：Camera is not loaded、Camera is loaded、Microphone is loaded和Microphone is not loaded。

问题：

问题是，这些信息同时显示两个文本。显示Camera is loaded和Camera not loaded。例如，当我第一次打开应用程序时，它显示Camera not loaded。当我按下按钮启用相机时，文本显示相机已加载，但问题是未加载的文本相机没有删除。它同时显示消息Camera is loaded和Camera not loaded。如果我退出程序并再次加载已解决的问题，它只显示消息camera is loaded。我想刷新新消息而不退出程序并再次加载。

有人能帮我解决这个问题吗？

这是Python程序：

def update():
root.after(1000, update)  # run itself again after 1000 ms
var1()
def var1():
var1 = StringVar()
exit_code_cam = os.system("lsmod |grep uvcvideo")
load = "Camera is loaded"
notLoad = "Camera not loaded"
if exit_code_cam == 0:
l1 = Label(root, textvariable=var1, fg="green")
l1.place(x=2, y=30)
var1.set(load)
else:
l1 = Label(root, textvariable=var1, fg="red")
l1.place(x=2, y=10)
var1.set(notLoad)
def button_add1():
cam_mic_bash.enable_cam()
var1()
def button_add3():
cam_mic_bash.disable_cam()
var1()
# Define Buttons
button_1 = Button(root, text="Allow camera", width=20, height=5, padx=0, pady=0, command=button_add1)
button_3 = Button(root, text="Block camera", width=20, height=5, padx=0, pady=0, command=button_add3)
# Put the buttons on the screen
button_1.place(x=0, y=75)
button_3.place(x=0, y=150)
# run first time
update()
root.mainloop()

Answer 1

与其一次又一次地创建新标签，不如创建一次标签并根据您的需求进行配置，ála

import os
from tkinter import StringVar, Tk, Label, Button
root = Tk()
camera_loaded_stringvar = StringVar()
camera_label = Label(root, textvariable=camera_loaded_stringvar)
camera_label.place(x=2, y=10)
def update_loop():
root.after(1000, update_loop)  # run itself again after 1000 ms
update_camera_label()

def update_camera_label():
is_loaded = os.system("lsmod | grep uvcvideo") == 0
if is_loaded:
camera_loaded_stringvar.set("Camera is loaded")
camera_label.configure(fg="green")
else:
camera_loaded_stringvar.set("Camera not loaded")
camera_label.configure(fg="red")

def button_add1():
enable_cam()
update_camera_label()

def button_add3():
disable_cam()
update_camera_label()

allow_camera_button = Button(root, text="Allow camera", width=20, height=5, padx=0, pady=0, command=button_add1)
block_camera_button = Button(root, text="Block camera", width=20, height=5, padx=0, pady=0, command=button_add3)
allow_camera_button.place(x=0, y=75)
block_camera_button.place(x=0, y=150)
update_loop()
root.mainloop()