效果如图：
风机具备调节转速的功能，转速通过扇叶旋转的快慢来区别，共分为四档，其中零档为静止状态，而一、二、三档则依次增加转速。在代码中，BlowerWrapper 类包含了可旋转的扇叶、风机外框以及选项三个主要部分。此处有两处关键点值得注意：
- BlowerWrapper 选择继承 QObject 的主要原因是为了配合 QPropertyAnimation 的使用，由于普通的 QGraphicsItem 并未继承 QObject，无法使用 QPropertyAnimation 增加动画功能。
- fan_item 、option （包括 option1、option2、option3）均使用 setParentItem 方法将 blower_base 设置为它们的父对象，这样便于它们随父对象一起移动。之所以没有使用 group ，是因为使用 group 后，item 将无法接收到鼠标的点击事件。见(https://stackoverflow.com/questions/60476803/how-to-propagate-mouse-events-to-a-qgraphicsitem-in-a-qgraphicsitemgroup)
下面是代码，同步于gitcode https://gitcode.com/m0_37662818/fan
from PyQt5.QtCore import *
from PyQt5.QtCore import pyqtProperty
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *import sysclass MySignal(QObject):fan_singal = pyqtSignal(int)class clickedRectItem(QGraphicsRectItem):def __init__(self, level = None, parent=None):super().__init__(parent)self.level = levelself.signal = MySignal()def mousePressEvent(self, event):if event.button() == Qt.MouseButton.LeftButton:if self.level is not None:self.signal.fan_singal.emit(self.level)return super().mousePressEvent(event)class BlowerWrapper(QObject):def __init__(self, parent=None):super().__init__(parent)fan_pixmap = QPixmap("./fan.png")blower_frame_pixmap = QPixmap("./blower_frame.png")self.fan_item = QGraphicsPixmapItem(fan_pixmap)self.blower_base = QGraphicsPixmapItem(blower_frame_pixmap)self.option1 = clickedRectItem(level=1)self.option2 = clickedRectItem(level=2)self.option3 = clickedRectItem(level=3)self.fan_item.setParentItem(self.blower_base)self.option1.setParentItem(self.blower_base)self.option2.setParentItem(self.blower_base)self.option3.setParentItem(self.blower_base)self.fan_item.setTransformOriginPoint(self.fan_item.boundingRect().center())self.cal_rect()self.animation_init()self.option1.signal.fan_singal.connect(self.animate)self.option2.signal.fan_singal.connect(self.animate)self.option3.signal.fan_singal.connect(self.animate)self.blower_base.setFlag(QGraphicsItem.GraphicsItemFlag.ItemIsMovable, True)self.blower_base.setFlag(QGraphicsItem.GraphicsItemFlag.ItemIsSelectable, True)self.blower_base.setShapeMode(QGraphicsPixmapItem.ShapeMode.BoundingRectShape)self.level = 0def animation_init(self):self.anim = QPropertyAnimation(self, b'rotation')self.anim.setDuration(1600)self.anim.setStartValue(0)self.anim.setEndValue(360)self.anim.setLoopCount(-1)def animate(self,level:int = None):if level is None or level == self.level or level == 0:self.anim.stop()self.set_rect_color(0)self.level = 0returnelse:level = int(level)self.level = levelif level == 1:time = 1600elif level == 2:time = 700elif level == 3:time = 300else:returnself.anim.setDuration(time)self.set_rect_color(self.level)self.anim.start()def cal_rect(self):x_len = self.blower_base.boundingRect().width()y_len = self.blower_base.boundingRect().height()rect_side_length = x_len / 4x_space = (x_len - rect_side_length * 3 ) / 2x1 = 0.0 y1 = y_len + x_space / 2x2 = rect_side_length + x_spacey2 = y_len + x_space / 2x3 = rect_side_length * 2 + x_space * 2y3 = y_len + x_space / 2self.option1.setRect(QRectF(x1, y1, rect_side_length, rect_side_length))self.option2.setRect(QRectF(x2, y2, rect_side_length, rect_side_length))self.option3.setRect(QRectF(x3, y3, rect_side_length, rect_side_length))def _set_rotation(self, angle):self.fan_item.setRotation(angle)def set_rect_color(self, level:int):for item in [self.option1, self.option2, self.option3]:item.setBrush(QColor(255, 255, 255, 255))item.setPen(QColor(0,0,0,255))if level == 1:self.option1.setBrush(QColor(0, 128, 255, 255))self.option1.setPen(QColor(0, 128, 255, 255))elif level == 2:self.option2.setBrush(QColor(0, 128, 255, 255))self.option2.setPen(QColor(0, 128, 255, 255))elif level == 3:self.option3.setBrush(QColor(0, 128, 255, 255))self.option3.setPen(QColor(0, 128, 255, 255))rotation = pyqtProperty(int, fset=_set_rotation)class MainWindow(QGraphicsView):def __init__(self):super().__init__()self.scene_area = QGraphicsScene(self)self.scene_area.setSceneRect(0,0,300,300)self.setScene(self.scene_area)self.show()self.blower_wrapper = BlowerWrapper()self.scene_area.addItem(self.blower_wrapper.blower_base)self.blower_wrapper.blower_base.setPos(125,110)self.btn = QPushButton("开始")if __name__ == '__main__':app = QApplication(sys.argv)ex = MainWindow()sys.exit(app.exec_())
