PyQt5-QComboBox控件使用

QComboBox 中addItem("")添加單個選項； addItems(列表)添加多個選項；

例如：下面實現省市級聯效果如下：

#QComboBox下拉列表控件使用,省市級聯
from PyQt5.QtWidgets import  QPushButton,QVBoxLayout,QWidget,QApplication,QRadioButton,QHBoxLayout,QCheckBox,QGroupBox,QComboBox
from PyQt5.QtGui import QIcon,QPixmap
from PyQt5.QtCore import  Qt

import sys

class WindowClass(QWidget):

    def __init__(self,parent=None):
        self.citys = {"北京": ["北京"], "上海": ["上海"], "河北省": ["石家庄", "邯鄲"]}
        super(WindowClass, self).__init__(parent)
        layout=QVBoxLayout()
        self.comboBox_1=QComboBox()
        self.comboBox_1.addItem("--請選擇--")
        self.comboBox_1.addItem("北京")
        self.comboBox_1.addItem("上海")
        self.comboBox_1.addItem("河北省")
        self.comboBox_1.addItems(["湖南省","湖北省","天津"])

        self.comboBox_2 = QComboBox()
        self.comboBox_2.addItem("--請選擇--")

        layout.addWidget(self.comboBox_1)
        layout.addWidget(self.comboBox_2)
        self.comboBox_1.currentIndexChanged.connect(self.btnState)

        self.setLayout(layout)
    def btnState(self):
        print("狀態：",self.comboBox_1.currentText())
        # for count in range(self.comboBox_1.count()):
        #     print("列表選項:" ,self.comboBox_1.itemText(count),count)

        province=self.comboBox_1.currentText()
        print(province in  self.citys.keys())
        if province!="--請選擇--":
            self.comboBox_2.clear()
            self.comboBox_2.addItems(self.citys[province] if   province in  self.citys.keys() else ["--請選擇--"])
        else:
            self.comboBox_2.clear()
            self.comboBox_2.addItem("--請選擇--")



if __name__=="__main__":
    app=QApplication(sys.argv)
    win=WindowClass()
    win.show()
    sys.exit(app.exec_())