<p>下面是一个使用您的代码的工作解决方案。我把一个<code>centralWidget</code>和一个<code>centralLayout</code>添加到<code>QMainWindow</code>中,它现在保存您的<code>qbtn</code>:</p>
<pre><code>import sys
from PyQt4 import QtGui, QtCore
class Example(QtGui.QMainWindow):
def __init__(self):
super(Example, self).__init__()
self.initUI()
def initUI(self):
QtGui.QToolTip.setFont(QtGui.QFont('SansSerif', 10))
self.setToolTip('This is a <b>QWidget</b> Window widget')
exitAction = QtGui.QAction(QtGui.QIcon('exit-icon-2.png'), '&Exit', self)
exitAction.setShortcut('Ctrl+Q')
exitAction.setStatusTip('Exit/Terminate application')
exitAction.triggered.connect(QtGui.qApp.quit)
self.statusBar()
menubar = self.menuBar()
menubar.setToolTip('This is a <b>QWidget</b> for MenuBar')
fileMenu = menubar.addMenu('&File')
fileMenu.addAction(exitAction)
toolbar = self.addToolBar('Exit')
toolbar.addAction(exitAction)
# Create a central Widgets
centralWidget = QtGui.QWidget()
# Create a Layout for the central Widget
centralLayout = QtGui.QHBoxLayout()
qbtn = QtGui.QPushButton('Quit', self)
qbtn.setToolTip('This is a <b>QPushButton</b> widget')
qbtn.clicked.connect(self.launchAAA)
qbtn.resize(qbtn.sizeHint())
qbtn.move(170, 190)
# Add the Button to the Layout
centralLayout.addWidget(qbtn)
# Set the Layout
centralWidget.setLayout(centralLayout)
# Set the Widget
self.setCentralWidget(centralWidget)
self.setGeometry(500, 180, 400, 400)
self.setWindowTitle('Quit button with Message')
self.show()
def launchAAA(self, event):
reply = QtGui.QMessageBox.question(self, 'Message',
"Are you sure to quit?", QtGui.QMessageBox.Yes |
QtGui.QMessageBox.No, QtGui.QMessageBox.No)
if reply == QtGui.QMessageBox.Yes:
QtGui.QApplication.quit()
else:
pass
def main():
app = QtGui.QApplication(sys.argv)
ex=Example()
sys.exit(app.exec_())
if __name__ == '__main__':
main()
</code></pre>