# -*- coding: utf-8 -*-
import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
class ComboxDemo(QWidget):
  def __init__(self, parent=None):
    super(ComboxDemo, self).__init__(parent)
    self.setWindowTitle("combox 示例")
    self.resize(300, 90)                       
    layout = QVBoxLayout()
    self.lbl = QLabel("" )  
    self.cb = QComboBox()
    self.cb.addItem("C")
    self.cb.addItem("C++")
    self.cb.addItems(["Java", "C#", "Python"])
    self.cb.currentIndexChanged.connect(self.selectionchange)
    layout.addWidget(self.cb)
    layout.addWidget(self.lbl )
    self.setLayout(layout)
  def selectionchange(self,i):
    self.lbl.setText( self.cb.currentText() )
    self.lbl.adjustSize()
    print( "Items in the list are :" )
    for count in range(self.cb.count()):
      # 打印出所有的下拉框索引和名称 
      print( 'item'+str(count) + '='+ self.cb.itemText(count) )
      print( "Current index",i,"selection changed ",self.cb.currentText() )
if __name__ == '__main__':
  app = QApplication(sys.argv)
  comboxDemo = ComboxDemo()
  comboxDemo.show()
  sys.exit(app.exec_())