问QVariantAnimation of opacity :项目显示在动画的末尾

EN

import sys

from PyQt5 import QtWidgets, QtCore
from PyQt5.QtCore import Qt, QEasingCurve
from PyQt5.QtGui import QPixmap
from PyQt5.QtWidgets import QMainWindow, QGraphicsScene, QGraphicsView, QGraphicsPixmapItem, QGraphicsItem


class QStone(QGraphicsPixmapItem):
    def __init__(self):
        QGraphicsPixmapItem.__init__(self)

        white = QPixmap("white2.png")
        self.setPixmap(white.scaled(60, 60, Qt.KeepAspectRatio))
        self.w = self.boundingRect().width()
        self.h = self.boundingRect().height()


class QBoard(QGraphicsView):
    def __init__(self,scene):
        QGraphicsView.__init__(self)
        self.scene=scene
        self.setScene(scene)

    def display_stone(self, x, y):
        stone = QStone()
        stone.setZValue(10)
        stone.setOpacity(0)
        stone.setPos(x - stone.w / 2, y - stone.h / 2)
        self.scene.addItem(stone)

        animation = QtCore.QVariantAnimation(self.scene)
        animation.setDuration(3000)
        animation.valueChanged.connect(stone.setOpacity)
        # animation.setStartValue(0)
        # animation.setEndValue(1)
        animation.setParent(self.scene)
        animation.setEasingCurve(QEasingCurve.BezierSpline)
        animation.start()


class MainWindow(QMainWindow):
    def __init__(self):

        #all the usual stuff
        QMainWindow.__init__(self)
        centralWidget = QtWidgets.QWidget(self)
        self.setCentralWidget(centralWidget)
        mainLayout = QtWidgets.QGridLayout()
        centralWidget.setLayout(mainLayout)
        self.scene = QGraphicsScene()
        self.view = QBoard(self.scene)
        mainLayout.addWidget(self.view,0,0)
        self.scene.setSceneRect(-200.0,-150.0,400.0,300.0)

        self.view.display_stone(0,0)

app = QtWidgets.QApplication(sys.argv)
main_win = MainWindow()
main_win.show()
sys.exit(app.exec_())