用python qt4搞了個複製文件界面

下面是部份代碼：

# -*- coding: utf-8 -*-from PyQt4.QtCore import pyqtSignaturefrom PyQt4.QtGui import QDialogfrom PyQt4 import QtCore,QtGuifrom Ui_copyfile import Ui_copyfileimport shutilimport osclass copyfile(QDialog, Ui_copyfile):    """    Class documentation goes here.    """    def __init__(self, parent=None):        """        Constructor                @param parent reference to the parent widget (QWidget)        """        QDialog.__init__(self, parent)        self.setupUi(self)    @pyqtSignature("")    def on_startButton_clicked(self):        if not self.dstlineEdit.text() and not self.srclineEdit.text():           self.textBrowser.append("Input srcdir or dstdir")        filelist = []        if not os.path.exists(self.srclineEdit.text()):            self.textBrowser.append("%s Directory not exits!"%str(self.srclineEdit.text()))            raise SystemExit        for root,dirs,files in os.walk(str(self.srclineEdit.text())):            for file in files:                filename = os.path.join(root,file)                filelist.append(filename)        num = int(len(filelist))        self.progressBar.setMinimum(0)        self.progressBar.setMaximum(num)        for i,filename in enumerate(filelist):                self.textBrowser.append("Copy %s to %s" % (filename,str(self.dstlineEdit.text())))                self.progressBar.setValue(i+1)                shutil.copy2(filename,str(self.dstlineEdit.text()))if __name__ == "__main__":    import sys    app = QtGui.QApplication(sys.argv)    ui = copyfile()    ui.show()    sys.exit(app.exec_())