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#!/usr/bin/python # -*- coding: utf-8 -*- """ ZetCode PyQt4 tutorial In this example, we connect a signal of a QtGui.QSlider to a slot of a QtGui.QLCDNumber. author: Jan Bodnar website: zetcode.com last edited: October 2011 """ import sys from PyQt4 import QtGui, QtCore class Example(QtGui.QWidget): def __init__(self): super(Example, self).__init__() self.initUI() def initUI(self): lcd = QtGui.QLCDNumber(self) sld = QtGui.QSlider(QtCore.Qt.Horizontal, self) vbox = QtGui.QVBoxLayout() vbox.addWidget(lcd) vbox.addWidget(sld) self.setLayout(vbox) # Here we connect a valueChanged signal of the slider to the display slot of the lcd number. # The sender is an object that sends a signal. The receiver is the object that receives the signal. The slot is the method that reacts to the signal. sld.valueChanged.connect(lcd.display) self.setGeometry(300, 300, 250, 150) self.setWindowTitle(‘Signal & slot‘) self.show() def main(): app = QtGui.QApplication(sys.argv) ex = Example() sys.exit(app.exec_()) if __name__ == ‘__main__‘: main() -------------------------------------------------------------------------------- #!/usr/bin/python # -*- coding: utf-8 -*- """ ZetCode PyQt4 tutorial In this example, we reimplement an event handler. author: Jan Bodnar website: zetcode.com last edited: October 2011 """ import sys from PyQt4 import QtGui, QtCore class Example(QtGui.QWidget): def __init__(self): super(Example, self).__init__() self.initUI() def initUI(self): self.setGeometry(300, 300, 250, 150) self.setWindowTitle(‘Event handler‘) self.show() # In our example, we reimplement the keyPressEvent() event handler. def keyPressEvent(self, e): # If we click the Escape button, the application terminates. if e.key() == QtCore.Qt.Key_Escape: self.close() def main(): app = QtGui.QApplication(sys.argv) ex = Example() sys.exit(app.exec_()) if __name__ == ‘__main__‘: main() -------------------------------------------------------------------------------- #!/usr/bin/python # -*- coding: utf-8 -*- """ ZetCode PyQt4 tutorial In this example, we determine the event sender object. author: Jan Bodnar website: zetcode.com last edited: October 2011 """ import sys from PyQt4 import QtGui, QtCore class Example(QtGui.QMainWindow): def __init__(self): super(Example, self).__init__() self.initUI() def initUI(self): btn1 = QtGui.QPushButton("Button 1", self) btn1.move(30, 50) btn2 = QtGui.QPushButton("Button 2", self) btn2.move(150, 50) # Both buttons are connected to the same slot. btn1.clicked.connect(self.buttonClicked) btn2.clicked.connect(self.buttonClicked) self.statusBar() self.setGeometry(300, 300, 290, 150) self.setWindowTitle(‘Event sender‘) self.show() def buttonClicked(self): # We determine the signal source by calling the sender() method. In the statusbar of the application, we show the label of the button being pressed. sender = self.sender() self.statusBar().showMessage(sender.text() + ‘ was pressed‘) def main(): app = QtGui.QApplication(sys.argv) ex = Example() sys.exit(app.exec_()) if __name__ == ‘__main__‘: main() -------------------------------------------------------------------------------- #!/usr/bin/python # -*- coding: utf-8 -*- """ ZetCode PyQt4 tutorial In this example, we show how to emit a signal. author: Jan Bodnar website: zetcode.com last edited: January 2015 """ import sys from PyQt4 import QtGui, QtCore class Communicate(QtCore.QObject): # A signal is created with the QtCore.pyqtSignal() as a class attribute of the external Communicate class. closeApp = QtCore.pyqtSignal() class Example(QtGui.QMainWindow): def __init__(self): super(Example, self).__init__() self.initUI() def initUI(self): # The custom closeApp signal is connected to the close() slot of the QtGui.QMainWindow. self.c = Communicate() self.c.closeApp.connect(self.close) self.setGeometry(300, 300, 290, 150) self.setWindowTitle(‘Emit signal‘) self.show() # When we click on the window with a mouse pointer, the closeApp signal is emitted. The application terminates. def mousePressEvent(self, event): self.c.closeApp.emit() def main(): app = QtGui.QApplication(sys.argv) ex = Example() sys.exit(app.exec_()) if __name__ == ‘__main__‘: main()
ZetCode PyQt4 tutorial signals and slots
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原文地址:http://www.cnblogs.com/zengjfgit/p/4851613.html