comp_file.py

#!/usr/bin/python
# -*- coding: utf-8 -*-

import sys
from PyQt4 import QtGui, QtCore

class MyLineEdit(QtGui.QLineEdit):
        def __init__( self, parent=None ):
            super(MyLineEdit, self).__init__(parent)
            self.setDragEnabled(True)
        def dragEnterEvent( self, event ):
            data = event.mimeData()
            urls = data.urls()
            if ( urls and urls[0].scheme() == 'file' ):
                event.acceptProposedAction()
        def dragMoveEvent( self, event ):
            data = event.mimeData()
            urls = data.urls()
            if ( urls and urls[0].scheme() == 'file' ):
                event.acceptProposedAction()

        def dropEvent( self, event ):
            data = event.mimeData()
            urls = data.urls()
            if ( urls and urls[0].scheme() == 'file' ):
                filepath = str(urls[0].path())[1:]
                filepath=filepath.decode('utf-8')
                self.setText(filepath)

class CompTools(QtGui.QWidget):
    def __init__(self,label="label",content='',button=u"浏览"):
        super(CompTools, self).__init__()
        self._label=label
        self._line_content=content
        self._button=button
        self.initUI()
    def initUI(self):
        self.mylabel=QtGui.QLabel(self._label)
        self.mylineEdit=MyLineEdit()
        self.mylineEdit.setPlaceholderText(self._line_content)
        self.mybutton=QtGui.QPushButton(self._button)
        hbox = QtGui.QHBoxLayout()
        hbox.addWidget(self.mylabel)
        hbox.addWidget(self.mylineEdit)
        hbox.addWidget(self.mybutton)
        self.setLayout(hbox)
        self.setGeometry(300, 300, 390, 210)
        self.setWindowTitle('group widget')

        self.mybutton.clicked.connect(self.change_filepath)
        
        
        #self.show()
    def change_label(self,value):
        self.mylabel.setText(value)
    def change_content(self,value):
        self.mylineEdit.setPlaceholderText(value)
    def change_button(self,value):
        self.mybutton.setText(value)
    def change_filepath(self):
        filename=QtGui.QFileDialog.getExistingDirectory(self,                                             
                  u"choose directory",
                  r"C:\Users\Administrator\Desktop")
        self.mylineEdit.setText(filename)
        
def main():
    app = QtGui.QApplication(sys.argv)
    ex = CompTools(label="data:",content='data path (can drop)',button=u"浏览")
    ex.show()
    sys.exit(app.exec_())

    
if __name__ == '__main__':
    main()

之后使用时就可以把他们三个当成一个来使用。

new_tool.py

#!/usr/bin/python
# -*- coding: utf-8 -*-

import sys
from PyQt4 import QtGui, QtCore
from comp_file import CompTools


class Compview(QtGui.QWidget):
    def __init__(self):
        super(Compview, self).__init__()
        self.initUI()
    def initUI(self):
        self.myTools=CompTools(label="data:",content='data path (can drop)',button=u"浏览")
        
        #self.myTools.change_label("path:")
        
        self.myTree=QtGui.QTextEdit()
        ok=QtGui.QPushButton(u"确定")
        no=QtGui.QPushButton(u"取消")
        lbox = QtGui.QHBoxLayout()
        lbox.addWidget(ok)
        lbox.addWidget(no)
        
        hbox = QtGui.QVBoxLayout()
        hbox.addWidget(self.myTools)
        hbox.addWidget(self.myTree)

        lay=QtGui.QVBoxLayout()
        lay.addLayout(hbox)
        lay.addLayout(lbox)
        self.setLayout(lay)
        
        self.setGeometry(250,150,600,450)
        self.setWindowTitle('new widget')   
        #self.show()
 
        
def main():
    app = QtGui.QApplication(sys.argv)
    ex = Compview()
    ex.show()
    sys.exit(app.exec_())

    
if __name__ == '__main__':
    main()

想要改变标签，只需要改变参数就可以了。
CompTools(label=“data:”,content=‘data path (can drop)’,button=u"浏览")
也可以使用chang函数进行修改。