# -*- coding: utf-8 -*-
from PyQt4.QtGui import *
from PyQt4.QtCore import *
import PyQt4.Qt
import sys

class myLineEdit(QLineEdit):
    def valid(self):
        if self.text()==self.valval:
            return True
        else:
            return False

class ef(QObject):
    outFoc=None
    inFoc=None
    def eventFilter(self, ob, ev):
        if ev.type()==QEvent.FocusIn:
            print "in", ob.valval
            return False
        if ev.type()==QEvent.FocusOut:
            print "out",  ob.valval
            if ob.valid():
                return False
            else:
                return True
        return False

if __name__ == "__main__":
    app = QApplication(sys.argv)
    MyApp = QApplication(sys.argv)

    app = QApplication(sys.argv)
    q=QDialog()
    ef=ef()
    f=QFormLayout()
    l1=myLineEdit("1")
    l2=myLineEdit("2")
    l3=myLineEdit("3")
    l1.installEventFilter(ef)
    l2.installEventFilter(ef)
    l3.installEventFilter(ef)
    l1.valval="1"
    l2.valval="2"
    l3.valval="3"
    f.addRow("label 1", l1)
    f.addRow("label 2", l2)
    f.addRow("label 3", l3)

    q.setLayout(f)
    q.show()
    sys.exit(app.exec_())