Pyqt4 实现窗口全屏显示

#!/usr/bin/env python# -*- coding:utf-8 -*-#system importsimport sys#pyqt importsfrom PyQt4 import QtCore,QtGuifrom PyQt4.QtCore import Qtclass MainWindow(QtGui.QWidget):    def __init__(self):        QtGui.QWidget.__init__(self)        #初始化position        self.m_DragPosition=self.pos()        #screen = QtGui.QDesktopWidget().screenGeometry()        #self.resize(screen.width(), screen.height())         #self.resize(1280,800)        #self.setWindowFlags(Qt.FramelessWindowHint | Qt.WindowStaysOnTopHint)        self.setStyleSheet("background-color:#2C3E50;")        #按钮一        qbtn_one=QtGui.QPushButton(u"开始测试",self)        qbtn_one.setGeometry(400,360,120,80)        qbtn_one.setStyleSheet("QPushButton{background-color:#16A085;border:none;color:#ffffff;font-size:20px;}"                               "QPushButton:hover{background-color:#333333;}")        qbtn_close=QtGui.QPushButton(u"关闭此窗口",self)        qbtn_close.setGeometry(600,360,120,80)        qbtn_close.setStyleSheet("QPushButton{background-color:#D35400;border:none;color:#ffffff;font-size:20px;}"                                 "QPushButton:hover{background-color:#333333;}")        self.showFullScreen()    #全屏显示必须放在所有组件画完以后执行        #注册事件        self.connect(qbtn_one,QtCore.SIGNAL("clicked()"),QtGui.qApp,QtCore.SLOT("quit()"))        self.connect(qbtn_close,QtCore.SIGNAL("clicked()"),QtGui.qApp,QtCore.SLOT("quit()"))    def keyPressEvent(self, event):        if event.key() == QtCore.Qt.Key_A:            self.showFullScreen()        if event.key() == QtCore.Qt.Key_Escape:            self.showNormal()if __name__=="__main__":    mapp=QtGui.QApplication(sys.argv)    mw=MainWindow()    mw.show()    sys.exit(mapp.exec_())