如何更改 Tkinter 按钮状态？

Tkinter 是一个用于创建 GUI 应用程序的Python包。 Python有很多 GUI 框架，但 Tkinter 是唯一内置到Python标准库中的框架。 Tkinter 有几个优点；它是跨平台的，因此相同的代码适用于 Windows、macOS 和 Linux。与其他框架相比，Tkinter 是轻量级的，使用起来相对轻松。

在本文中，我们将学习如何更改按钮的状态。

让我们逐步理解这一点：

第 1 步：首先，我们将导入Tkinter模块和一些我们需要的小部件。

Python3

# importing tkinter module
# along with some constants and Widgets
  
from tkinter import Tk
from tkinter.constants import DISABLED, NORMAL
from tkinter.ttk import Button, Label

如果您使用的是 Python2，那么将tkinter更改为 Tkinter并且tkinter.ttk也将不起作用，因此从 Tkinter 本身导入小部件。

第 2 步：现在我们将创建一个包含所有按钮和标签的App 类。

蟒蛇3

# Creating App class which
# will contain our overall App
class App:
    def __init__(self, master) -> None:
  
        # Instantiating master i.e toplevel Widget
        self.master = master
  
        # Creating label
        self.label = Label(self.master,
                           text = "Click Button2 to change Button1 State")
        self.label.pack(pady = 10)
  
        # Creating button1
        # We will change the state of this Button
        # it has a initial state of "NORMAL" 
        # i.e Button can be pressed
        self.button1 = Button(self.master,
                              text = "Button1",
                              state = NORMAL)
          
        self.button1.pack(pady = 20)
  
        # Creating another button
        # We will use this button to
        # change the State of first button
        self.button2 = Button(self.master,
                              text = "Button2",
                              command = self.changeState)
          
        self.button2.pack(pady = 20)

第3步：正如你在上面的代码中看到的，我们有一个与Button2相连的函数，即changeState函数，接下来我们要实现这个函数。在这个函数中，我们将改变 Button1 的状态。

蟒蛇3

# Helper function which will change the State of Button1
def changeState(self) -> None:
  
    # Printing the State of 
    # the Button before ALTERING it
    # This is optional
    print(self.button1['state'])
  
    # Checking if the STATE of the Button1
  
    # If the STATE is NORMAL
    if (self.button1['state'] == NORMAL):
  
        # Change the state to DISABLED
        self.button1['state'] = DISABLED
    else:
        
        # Otherwise, change the state to NORMAL
        self.button1['state'] = NORMAL

第 4 步：在这一步中，我们将创建将运行此应用程序的主函数。在 main函数中，我们将设置应用程序标题和几何图形并实例化我们的 App 类。

蟒蛇3

if __name__ == "__main__":
  
    # Instantiating top level
    root = Tk()
  
    # Setting the title of the window
    root.title("Button State App")
  
    # Setting the geometry i.e Dimensions
    root.geometry("400x250")
  
    # Calling our App
    app = App(root)
  
    # Mainloop which will cause
    # this toplevel to run infinitely
    root.mainloop()

下面是完整的实现：

蟒蛇3

# importing tkinter module
# along with some constants and Widgets
from tkinter import Tk
from tkinter.constants import DISABLED, NORMAL
from tkinter.ttk import Button, Label
  
# Creating App class
# which will contain our overall App
class App:
    def __init__(self, master) -> None:
  
        # Instantiating master 
        # i.e toplevel Widget
        self.master = master
  
        # Creating label
        self.label = Label(self.master,
                           text="Click Button2 to change Button1 State")
          
        self.label.pack(pady = 10)
  
        # Creating button1
        # We will change the state of this Button
        # it has a initial state of 
        # "NORMAL" i.e Button can be pressed
        self.button1 = Button(self.master, 
                              text = "Button1", 
                              state = NORMAL)
          
        self.button1.pack(pady = 20)
  
        # Creating another button
        # We will use this button
        # to change the State of first button
        self.button2 = Button(self.master,
                              text = "Button2",
                              command = self.changeState)
          
        self.button2.pack(pady = 20)
  
    # Helper function which will 
    # change the State of Button1
    def changeState(self) -> None:
  
        # Printing the State of 
        # the Button before ALTERING it
        # This is optional
        print(self.button1['state'])
  
        # Checking if the STATE of the Button1
        # If the STATE is NORMAL
        if (self.button1['state'] == NORMAL):
  
            # Change the state to DISABLED
            self.button1['state'] = DISABLED
        else:
  
            # Otherwise, change the state to NORMAL
            self.button1['state'] = NORMAL
  
  
if __name__ == "__main__":
  
    # Instantiating top level
    root = Tk()
  
    # Setting the title of the window
    root.title("Button State App")
  
    # Setting the geometry i.e Dimensions
    root.geometry("400x250")
  
    # Calling our App
    app = App(root)
  
    # Mainloop which will cause this toplevel
    # to run infinitely
    root.mainloop()

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