滑块数字的使用

代码：
 1 #coding: utf-8
 2 import sys
 3 from PyQt4.QtGui import *
 4 from PyQt4.QtCore import *
 5 
 6 
 7 class sigsort(QWidget):
 8     def __init__(self, parent=None):
 9         QWidget.__init__(self, parent)
10 
11         self.setWindowTitle(self.tr("num"))
12         lcd = QLCDNumber(self)
13         slider = QSlider(Qt.Horizontal, self)
14 
15         vbox = QVBoxLayout()
16         vbox.addWidget(lcd)
17         vbox.addWidget(slider)
18 
19         self.setLayout(vbox)
20         self.connect(slider, SIGNAL('valueChanged(int)'), lcd, SLOT('display(int)'))
21         self.resize(250, 150)
22 app = QApplication(sys.argv)
23 qb = sigsort()
24 qb.show()
25 sys.exit(app.exec_())