#!/usr/bin/env python
from PyQt5.QtWidgets import (QApplication, QWidget, QComboBox, QDialog,
        QDialogButtonBox, QFormLayout, QGridLayout, QGroupBox, QHBoxLayout,
        QLabel, QLineEdit, QMenu, QMenuBar, QPushButton, QSpinBox, QTextEdit,
        QVBoxLayout, QGraphicsView, QGraphicsScene, QGraphicsItem, QGraphicsPixmapItem)
from PyQt5.QtGui import (QIcon, QPixmap, QBrush, QPen, QColor)
from PyQt5 import QtCore
from PyQt5.QtCore import (QLineF, QPointF, QRectF, Qt)

import sys
import os
import re


class Test_graphics(QGraphicsItem):
    def __init__(self):
        super(Test_graphics, self).__init__()
        self.time = 0
        self.a = 1

    def paint(self, painter, option, widget):
        painter.setPen(Qt.black)
        i = self.time
        painter.drawEllipse(i, i, 10, 10)
　　　　　　　　#下の関数を入れないとうまく表示が更新されない。
    def boundingRect(self):
        return QRectF(0,0,400,400)

    def redraw(self):
        if self.time == 0:
            self.a = 1
        elif self.time >= 390:
            self.a = -1
        else:
            pass
        x = self.time + 10*self.a
        self.time = x
        self.update()

class MainWindow(QWidget):

    def __init__(self,parent=None):
        super(MainWindow, self).__init__(parent)
        path = os.path.join(os.path.dirname(sys.modules[__name__].__file__), 'ico.png')
        view = QGraphicsView()
        scene = QGraphicsScene()
        self.item = Test_graphics()
        view.setSceneRect(0, 0, 400, 400);
        scene.addItem(self.item)
        view.setScene(scene)
        mainLayout = QVBoxLayout()
        mainLayout.addWidget(view)
        self.setLayout(mainLayout)
        #windowのタイトル変更
        self.setWindowTitle("Test App6")

    def mousePressEvent(self, event):
        self.item.redraw()
        super(MainWindow, self).mousePressEvent(event)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    path = os.path.join(os.path.dirname(sys.modules[__name__].__file__), 'ico.png')
    app.setWindowIcon(QIcon(path))
    P = MainWindow()
    P.show()
    sys.exit(app.exec_())