目标是将TicTacToe
这个顶级类的信号与类连接起来。
它会抛出一个错误:TicTacToe无法在此上下文中转换为PyQt5.QtCore.QObject
#!/usr/bin/env python
from PyQt5.QtCore import (QLineF, QPointF, QRectF, pyqtSignal)
from PyQt5.QtGui import (QIcon, QBrush, QColor, QPainter, QPixmap)
from PyQt5.QtWidgets import (QAction, QMainWindow, QApplication, QGraphicsView, QGraphicsScene, QGraphicsItem,
QGridLayout, QVBoxLayout, QHBoxLayout,
QLabel, QLineEdit, QPushButton)
class TicTacToe(QGraphicsItem):
def __init__(self):
super(TicTacToe, self).__init__()
def paintEvent(self, painter, option, widget):
painter.setPen(Qt.black)
painter.drawLine(0,100,300,100)
def boundingRect(self):
return QRectF(0,0,300,300)
def mousePressEvent(self, event):
pos = event.pos()
self.select(int(pos.x()/100), int(pos.y()/100))
self.update()
super(TicTacToe, self).mousePressEvent(event)
messageSignal = pyqtSignal(int)
class MyGraphicsView(QGraphicsView):
def __init__(self):
super(MyGraphicsView, self).__init__()
scene = QGraphicsScene(self)
self.tic_tac_toe = TicTacToe()
scene.addItem(self.tic_tac_toe)
scene.addPixmap(QPixmap("exit.png"))
self.setScene(scene)
def keyPressEvent(self, event):
key = event.key()
if key == Qt.Key_R:
self.tic_tac_toe.reset()
super(MyGraphicsView, self).keyPressEvent(event)
class Example(QMainWindow):
def __init__(self):
super(Example, self).__init__()
self.y = MyGraphicsView()
self.setCentralWidget(self.y)
self.y.tic_tac_toe.messageSignal.connect (self.messageSlot)
self.initUI()
def messageSlot(self, val):
self.statusBar().showMessage(val)
def initUI(self):
self.toolbar = self.addToolBar('Tools')
self.setGeometry(30, 30, 30, 20)
self.setWindowTitle('Menubar')
self.show()
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
mainWindow = Example()
mainWindow.showFullScreen()
sys.exit(app.exec_())
QGraphicsItem
并没有继承自QObject
,但是QGraphicsObject
同时继承了QGraphicsItem
和QObject
。因此,在我看来,在这种情况下用QGraphicsObject
替换QGraphicsItem
应该完全可以胜任。 - G.M.