PyQt5 – 切换按钮

在 PyQt5 中，切换按钮基本上是处于特殊状态的按钮。按钮是一个按钮，当我们按下它时，它会执行一些任务并恢复正常状态。它类似于键盘键，当我们按下它时，它会做一些事情，当我们释放它时，它会恢复到原来的形式。

ToggleButton是一种按钮，但它有两种状态，即当我们按下它时，它不会恢复到原始状态。切换按钮类似于电源开关，当我们按下它时，它会保持打开状态，当我们关闭它时，它会保持在关闭位置。

In order to create toggle button we have to do the following:

1. Create a push button.
2. Set checkable to True i.e if it get pressed it get checked and if it get pressed again it get unchecked similar to check box.
3. Set calling method which get called when button is pressed.
4. In calling method check if the button is checked or not.
5. If button is checked change its color else set the default color to it.

下面是实现。

# importing the required libraries
  
from PyQt5.QtCore import * 
from PyQt5.QtGui import * 
from PyQt5.QtWidgets import * 
import sys
  
  
class Window(QMainWindow):
    def __init__(self):
        super().__init__()
  
        # set the title
        self.setWindowTitle("Python")
  
        # setting geometry
        self.setGeometry(100, 100, 600, 400)
  
        # creating a push button
        self.button = QPushButton("Toggle", self)
  
        # setting geometry of button
        self.button.setGeometry(200, 150, 100, 40)
  
        # setting checkable to true
        self.button.setCheckable(True)
  
        # setting calling method by button
        self.button.clicked.connect(self.changeColor)
  
        # setting default color of button to light-grey
        self.button.setStyleSheet("background-color : lightgrey")
  
        # show all the widgets
        self.update()
        self.show()
  
    # method called by button
    def changeColor(self):
  
        # if button is checked
        if self.button.isChecked():
  
            # setting background color to light-blue
            self.button.setStyleSheet("background-color : lightblue")
  
        # if it is unchecked
        else:
  
            # set background color back to light-grey
            self.button.setStyleSheet("background-color : lightgrey")
  
  
  
# create pyqt5 app
App = QApplication(sys.argv)
  
# create the instance of our Window
window = Window()
  
# start the app
sys.exit(App.exec())

输出 ：