mousepressevent的问题

Question

我刚问了一个类似的问题但是(对不起!)我想我需要更多的帮助.pyqt中的信号有问题.让我发布整个代码,它不长,我更容易解释...

from PyQt4 import QtGui, QtCore, Qt
import time
import math

class FenixGui(QtGui.QWidget):

    def backgroundmousepressevent(self, event):
        print "test 1"
        self.offset = event.pos()


    def backgroundmousemoveevent(self, event):
        print "test 2"
        x=event.globalX()
        y=event.globalY()
        x_w = self.offset.x()
        y_w = self.offset.y()
        self.move(x-x_w, y-y_w)


    def __init__(self):
        super(FenixGui, self).__init__()

        # setting layout type
        hboxlayout = QtGui.QHBoxLayout(self)
        self.setLayout(hboxlayout)

        # hiding title bar
        self.setWindowFlags(QtCore.Qt.FramelessWindowHint)

        # setting window size and position
        self.setGeometry(200, 200, 862, 560)
        self.setAttribute(Qt.Qt.WA_TranslucentBackground)
        self.setAutoFillBackground(False)

        # creating background window label
        backgroundpixmap = QtGui.QPixmap("fenixbackground.png")
        self.background = QtGui.QLabel(self)
        self.background.setPixmap(backgroundpixmap)
        self.background.setGeometry(0, 0, 862, 560)

        # making window draggable by the window label
        self.connect(self.background,QtCore.SIGNAL("mousePressEvent()"),         self.backgroundmousepressevent)
        self.connect(self.background,QtCore.SIGNAL("mouseMoveEvent()"), self.backgroundmousemoveevent)


        # fenix logo
        logopixmap = QtGui.QPixmap("fenixlogo.png")
        self.logo = QtGui.QLabel(self)
        self.logo.setPixmap(logopixmap)
        self.logo.setGeometry(100, 100, 400, 150)


def main():

    app = QtGui.QApplication([])
    exm = FenixGui()
    exm.show()
    app.exec_()


if __name__ == '__main__':
    main()

好吧,所以这就是代码,它只是一个简单的gui,我想在屏幕上点击并拖动背景中的任何地方进行拖动.我的问题是:backgroundmousepressevent和backgroundmousemoveevent当我按下或移动按钮时不要被解雇.所以我想知道:错误在哪里？我错了什么或什么？非常感谢你!

马特奥

Answer 1

在Qt中,事件与信号和插槽不同.事件由QEvent传递给s event()方法的对象表示QObject,通常将它们分派给专门的方法,如mousePressEvent和mouseMoveEvent.由于它们不是信号,因此无法将它们连接到插槽.

相反,只需重新实现事件函数来执行自定义操作.super但是,确保调用原始实现,除非您知道自己在做什么.

def mousePressEvent(self, event):
    super(FenixGui, self).mousePressEvent(event)
    print "test 1"
    self.offset = event.pos()

def mouseMoveEvent(self, event):
    super(FenixGui, self).mouseMoveEvent(event)
    print "test 2"
    x=event.globalX()
    y=event.globalY()
    x_w = self.offset.x()
    y_w = self.offset.y()
    self.move(x-x_w, y-y_w)

通常,Qt会在尝试连接到不存在的信号时通过向控制台写入警告消息来警告您.此外,您可以通过使用新式信号和插槽而不是旧式更多C++ - ish SIGNAL()函数来防止这种情况:

lineEdit = QtGui.QLineEdit()
lineEdit.valueChanged.connect(self.myHandlerMethod)