Python PyQt4 Downloader with progressbar

myDownloader.py

# -*- coding: utf-8 -*-

from PyQt4 import QtCore, QtGui
from PyQt4.QtGui import *
from PyQt4.QtCore import *
from urllib2 import *

class DownloaderApp(QtGui.QMainWindow):
    def __init__(self, parent = None):
        super(DownloaderApp, self).__init__(parent)
        
        self.setObjectName("download")
        
        self.groupBox = QtGui.QGridLayout()
        self.groupBox.setObjectName("groupBox")
        
        self.resize(500, 150)
        
        self.progressBar = QtGui.QProgressBar()
        self.progressBar.setLayoutDirection(QtCore.Qt.LeftToRight)
        self.progressBar.setProperty("value", 0)
        self.progressBar.setObjectName("progressBar")
        self.progressBar.setVisible(False)
        self.progressBar.setStyleSheet(stylesheet(self))
        
        self.plainTextEdit = QtGui.QLineEdit()
        self.plainTextEdit.setObjectName("plainTextEdit")
        self.plainTextEdit.text()==''
        
        self.pushButton = QtGui.QPushButton()
        self.pushButton.setCursor(QtGui.QCursor(QtCore.Qt.PointingHandCursor))
        self.pushButton.setObjectName("pushButton")
        self.pushButton.setFixedWidth(130)
        self.pushButton.setText("start Download")        
               
        self.label = QtGui.QLabel()
        self.label.setObjectName("label")
        self.label.setText("URL:")
        
        self.statuslabel = QtGui.QLabel()
        self.statuslabel.setText("status")
        
        self.groupBox.addWidget(self.label, 0, 0 ) 
        self.groupBox.addWidget(self.plainTextEdit, 1, 0 , 1, 1)
        self.groupBox.addWidget(self.pushButton, 2, 0)
        self.groupBox.addWidget(self.progressBar, 3, 0, 1, 2)
        self.groupBox.addWidget(self.statuslabel, 4, 0, 1, 1 , Qt.AlignBottom)
        
        qw = QtGui.QWidget()
        qw.setLayout(self.groupBox)
        
        self.setCentralWidget(qw)
        
        self.setWindowTitle("Downloader")                
    
        QtCore.QObject.connect(self.pushButton, QtCore.SIGNAL("clicked()"), self.startDownload)
        QtCore.QObject.connect(self.pushButton, QtCore.SIGNAL("clicked()"), self.plainTextEdit.clear)
        QtCore.QMetaObject.connectSlotsByName(self)
        
        
    def startDownload(self):
        if not self.plainTextEdit.text() or self.plainTextEdit.text()=='':
                QMessageBox.information(myDownloader,"Warning","no link")
                return
        self.progressBar.setVisible(True)
        QtGui.QApplication.processEvents(QtCore.QEventLoop.AllEvents)
        enter=self.plainTextEdit.text()
        url=urlopen(('%s')%(enter))
        html=url.info()
        name = enter.split('/')[-1]
        name = QDir.homePath() + "/Downloads/" + name
        cl=html['Content-Length']
        f =open(name,'wb+')
        fl=0
        self.fl=0
        while 1:
             QtGui.QApplication.processEvents(QtCore.QEventLoop.AllEvents)
             xr=url.read(1024)
             fl+=len(xr)
             self.progressBar.setValue(fl*100/int(cl))
             QtGui.qApp.processEvents()
             f.write(xr)
             if not xr:break
             del xr
             QtGui.QApplication.processEvents(QtCore.QEventLoop.AllEvents)
        f.close()
        QMessageBox.information(myDownloader,"Message","Download complete")
        self.progressBar.setVisible(False)
        return

def stylesheet(self):
    return """
QProgressBar {
    border: 2px solid #D9D9D9;
    border-radius: 5px;
    text-align: center;
}

QProgressBar::chunk {
    background-color: #05B8CC;
    width: 20px;
}
    """   
    
if __name__ == "__main__":
    import sys
    app = QtGui.QApplication(sys.argv)
    myDownloader = DownloaderApp()
    myDownloader.show()
    sys.exit(app.exec_())