pyQt 使用Svg图像的悬停事件

Question

我已经在这个问题上纠结了一段时间了，还是搞不明白自己哪里出错了。希望这里有人能帮我。

我想让鼠标悬停在QGraphicsScene中的Svg元素上时能够触发一些事件。下面是我一直在尝试的代码。

#!/usr/bin/python

import sys
from PyQt4.QtGui import *
from PyQt4.QtCore import *
from PyQt4.QtSvg import *

class Main(QWidget):

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

        hbox = QHBoxLayout()

        self.setLayout(hbox)
        self.view = MyView(self)
        self.scene = QGraphicsScene()
        self.view.setScene(self.scene)

        hbox.addWidget(self.view)


class MyView(QGraphicsView):

    def __init__(self, parent):
        super(MyView, self).__init__(parent)
        self.parent = parent

    def mousePressEvent(self, event):
        super(MyView, self).mousePressEvent(event)
        test = MySvg()
        self.parent.scene.addItem(test.image)


class MySvg(QGraphicsSvgItem):

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

        self.image = QGraphicsSvgItem('ubuntu.svg')
        self.image.setFlags(QGraphicsItem.ItemIsSelectable|
                            QGraphicsItem.ItemIsMovable)

        self.setAcceptsHoverEvents(True)

    def hoverEnterEvent(self, event):
        print 'Enter'

    def hoverLeaveEvent(self, event):
        print 'Leave'

    def hoverMoveEvent(self, event):
        print 'Moving'


def runMain():

    app = QApplication(sys.argv)
    ex = Main()
    ex.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    runMain()

希望有人能帮忙。

Answer 1

你正在监控 MySvg 的悬停事件，但你却在视图中添加了另一个 QGraphicsSvgItem，这个项只是 MySvg 中的一个实例（MySvg.image）。而且你的 MySvg 根本没有在视图里。试试这样做：

#!/usr/bin/python

import sys
from PyQt4.QtGui import *
from PyQt4.QtCore import *
from PyQt4.QtSvg import *

class Main(QWidget):

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

        hbox = QHBoxLayout()

        self.setLayout(hbox)
        self.view = MyView(self)
        self.scene = QGraphicsScene()
        self.view.setScene(self.scene)

        hbox.addWidget(self.view)


class MyView(QGraphicsView):

    def __init__(self, parent):
        super(MyView, self).__init__(parent)
        self.parent = parent

    def mousePressEvent(self, event):
        super(MyView, self).mousePressEvent(event)
        test = MySvg()
        self.parent.scene.addItem(test)


class MySvg(QGraphicsSvgItem):

    def __init__(self):
        super(MySvg, self).__init__('ubuntu.svg')

        self.setFlags(QGraphicsItem.ItemIsSelectable|
                      QGraphicsItem.ItemIsMovable)

        self.setAcceptsHoverEvents(True)

    def hoverEnterEvent(self, event):
        print 'Enter'

    def hoverLeaveEvent(self, event):
        print 'Leave'

    def hoverMoveEvent(self, event):
        print 'Moving'


def runMain():

    app = QApplication(sys.argv)
    ex = Main()
    ex.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    runMain()