PyQt5 – 计算组合框中的项目数

在这篇文章中，我们将看到如何找到组合框中的项目总数。我们知道我们可以通过addItem方法在组合框中添加单项，addItems方法在组合框中添加多项。为了获得组合框中所有项目的数量，我们将使用count方法。

语法： combo_box.count()

参数： 它不需要参数

返回： 它将返回整数，即组合框中的项目数。

实现步骤：

1.创建一个组合框

2.在组合框中添加项目

3.创建按钮

4.给按钮添加动作

5.创建标签以显示计数

6.在动作中用count方法计算组合框中的项目，并将其存储在变量中

7.用setText方法的帮助在标签中显示计数变量。

# importing libraries
from PyQt5.QtWidgets import *
from PyQt5 import QtCore, QtGui
from PyQt5.QtGui import *
from PyQt5.QtCore import *
import sys
 
 
class Window(QMainWindow):
 
    def __init__(self):
        super().__init__()
 
        # setting title
        self.setWindowTitle("Python ")
 
        # setting geometry
        self.setGeometry(100, 100, 600, 400)
 
        # calling method
        self.UiComponents()
 
        # showing all the widgets
        self.show()
 
    # method for widgets
    def UiComponents(self):
 
        # creating a combo box widget
        self.combo_box = QComboBox(self)
 
        # setting geometry of combo box
        self.combo_box.setGeometry(200, 150, 120, 30)
 
        # geek list
        geek_list = ["Geek", "Geeky Geek", "Legend Geek", "Ultra Legend Geek"]
 
        # adding list of items to combo box
        self.combo_box.addItems(geek_list)
 
        # creating push button to clear the list
        button = QPushButton("Find Count ", self)
 
        print(self.combo_box.count())
 
        # adding action to button
        button.pressed.connect(self.find_count)
 
        # creating label to show count
        self.label = QLabel(self)
 
        # setting geometry of the label
        self.label.setGeometry(200, 200, 200, 30)
 
    def find_count(self):
 
        # finding the number of items in combo box
        count = self.combo_box.count()
 
        # showing count on the screen through label
        self.label.setText("Total number of  items : " + str(count))
 
# create pyqt5 app
App = QApplication(sys.argv)
 
# create the instance of our Window
window = Window()
 
# start the app
sys.exit(App.exec())