我写了以下简单的代码作为示例。它只是在点击按钮时打开一个新窗口。如果这个窗口已经存在于屏幕上,我找不到防止它重新打开的方法。我想要在窗口已经存在的情况下打开一个QDialog警告,并且主要是通过closeEvent方法向Mainwidget发送信号,说明新窗口已关闭。这将允许再次打开newWidget。
import sys
from PyQt4 import QtCore, QtGui
class NewWidget(QtGui.QWidget):
def __init__(self, parent=None):
super(NewWidget,self).__init__(parent)
self.lineEdit = QtGui.QLineEdit('new window',self)
self.resize(200,50)
self.show()
def closeEvent(self,ev):
self.Exit = QtGui.QMessageBox.question(self,
"Confirm Exit...",
"Are you sure you want to exit ?",
QtGui.QMessageBox.Yes| QtGui.QMessageBox.No)
ev.ignore()
if self.Exit == QtGui.QMessageBox.Yes:
ev.accept()
class MainWidget(QtGui.QWidget):
def __init__(self, parent=None):
super(MainWidget,self).__init__(parent)
self.button = QtGui.QPushButton("button", self)
self.button.clicked.connect(self.open_new)
def open_new(self):
self.new = NewWidget()
if __name__ == "__main__":
app = QtGui.QApplication(sys.argv)
main = MainWidget()
main.resize(200,50)
main.move(app.desktop().screen().rect().center() - main.rect().center())
main.show()
sys.exit(app.exec_())