python3+PyQt5实现自定义流体混合窗口部件

#!/usr/bin/env python3from PyQt5.QtCore import (QPointF, QSize, Qt,pyqtSignal)from PyQt5.QtWidgets import (QApplication,  QFrame, QLabel,  QSizePolicy, QSpinBox, QWidget)from PyQt5.QtGui import QColor,QPainter,QFontMetricsF,QBrush,QLinearGradient,QPolygon,QPolygonFclass YPipeWidget(QWidget): signal_valuechanged = pyqtSignal(int,int) def __init__(self, leftFlow=0, rightFlow=0, maxFlow=100,     parent=None):  super(YPipeWidget, self).__init__(parent)  self.leftSpinBox = QSpinBox(self)  self.leftSpinBox.setRange(0, maxFlow)  self.leftSpinBox.setValue(leftFlow)  self.leftSpinBox.setSuffix(" l/s")  self.leftSpinBox.setAlignment(Qt.AlignRight|Qt.AlignVCenter)  self.leftSpinBox.valueChanged.connect(self.valueChanged)  self.rightSpinBox = QSpinBox(self)  self.rightSpinBox.setRange(0, maxFlow)  self.rightSpinBox.setValue(rightFlow)  self.rightSpinBox.setSuffix(" l/s")  self.rightSpinBox.setAlignment(Qt.AlignRight|Qt.AlignVCenter)  self.rightSpinBox.valueChanged.connect(self.valueChanged)  self.label = QLabel(self)  self.label.setFrameStyle(QFrame.StyledPanel|QFrame.Sunken)  self.label.setAlignment(Qt.AlignCenter)  fm = QFontMetricsF(self.font())  self.label.setMinimumWidth(fm.width(" 999 l/s "))  self.setSizePolicy(QSizePolicy(QSizePolicy.Expanding,          QSizePolicy.Expanding))  self.setMinimumSize(self.minimumSizeHint())  self.valueChanged() def valueChanged(self):  a = self.leftSpinBox.value()  b = self.rightSpinBox.value()  self.label.setText("{0} l/s".format(a + b))  self.signal_valuechanged.emit(a,b)  self.update() def values(self):  return self.leftSpinBox.value(), self.rightSpinBox.value() def minimumSizeHint(self):  return QSize(self.leftSpinBox.width() * 3,      self.leftSpinBox.height() * 5) def resizeEvent(self, event=None):  fm = QFontMetricsF(self.font())  x = (self.width() - self.label.width()) / 2  y = self.height() - (fm.height() * 1.5)  self.label.move(x, y)  y = self.height() / 60.0  x = (self.width() / 4.0) - self.leftSpinBox.width()  self.leftSpinBox.move(x, y)  x = self.width() - (self.width() / 4.0)  self.rightSpinBox.move(x, y) def paintEvent(self, event=None):  LogicalSize = 100.0  def logicalFromPhysical(length, side):   return (length / side) * LogicalSize  fm = QFontMetricsF(self.font())  ymargin = ((LogicalSize / 30.0) +     logicalFromPhysical(self.leftSpinBox.height(),          self.height()))  ymax = (LogicalSize -    logicalFromPhysical(fm.height() * 2, self.height()))  width = LogicalSize / 4.0  cx, cy = LogicalSize / 2.0, LogicalSize / 3.0  ax, ay = cx - (2 * width), ymargin  bx, by = cx - width, ay  dx, dy = cx + width, ay  ex, ey = cx + (2 * width), ymargin  fx, fy = cx + (width / 2), cx + (LogicalSize / 24.0)  gx, gy = fx, ymax  hx, hy = cx - (width / 2), ymax  ix, iy = hx, fy  painter = QPainter(self)  painter.setRenderHint(QPainter.Antialiasing)  side = min(self.width(), self.height())  painter.setViewport((self.width() - side) / 2,       (self.height() - side) / 2, side, side)  painter.setWindow(0, 0, LogicalSize, LogicalSize)  painter.setPen(Qt.NoPen)  gradient = QLinearGradient(QPointF(0, 0),           QPointF(0, 100))  gradient.setColorAt(0, Qt.white)  a = self.leftSpinBox.value()  gradient.setColorAt(1, (Qt.red if a != 0 else Qt.white))  painter.setBrush(QBrush(gradient))  painter.drawPolygon(QPolygonF([QPointF(ax, ay), QPointF(bx, by), QPointF(cx, cy), QPointF(ix, iy)]))  gradient = QLinearGradient(QPointF(0, 0), QPointF(0, 100))  gradient.setColorAt(0, Qt.white)  b = self.rightSpinBox.value()  gradient.setColorAt(1, (Qt.blue if b != 0        else Qt.white))  painter.setBrush(QBrush(gradient))  painter.drawPolygon(QPolygonF([QPointF(cx, cy), QPointF(dx, dy),QPointF(ex, ey),QPointF(fx, fy)]))  if (a + b) == 0:   color = QColor(Qt.white)  else:   ashare = (a / (a + b)) * 255.0   bshare = 255.0 - ashare   color = QColor(ashare, 0, bshare)  gradient = QLinearGradient(QPointF(0, 0), QPointF(0, 100))  gradient.setColorAt(0, Qt.white)  gradient.setColorAt(1, color)  painter.setBrush(QBrush(gradient))  painter.drawPolygon(QPolygonF(    [QPointF(cx, cy),QPointF(fx, fy),QPointF(gx, gy), QPointF(hx, hy),QPointF(ix, iy)]))  painter.setPen(Qt.black)  painter.drawPolyline(QPolygonF([QPointF(ax, ay), QPointF(ix, iy),QPointF(hx, hy)]))  painter.drawPolyline(QPolygonF([QPointF(gx, gy), QPointF(fx, fy), QPointF(ex, ey)]))  painter.drawPolyline(QPolygonF([QPointF(bx, by), QPointF(cx, cy), QPointF(dx, dy)]))if __name__ == "__main__": import sys def valueChanged(a, b):  print(a, b) app = QApplication(sys.argv) form = YPipeWidget() form.signal_valuechanged.connect(valueChanged) form.setWindowTitle("YPipe") form.move(0, 0) form.show() form.resize(400, 400) app.exec_()