void Battery::paintEvent(QPaintEvent *)
{//绘制准备工作,启用反锯齿QPainter painter(this);painter.setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing);//绘制边框drawBorder(&painter);//绘制背景drawBg(&painter);//绘制头部drawHead(&painter);
}void Battery::drawBorder(QPainter *painter)
{painter->save();double headWidth = width() / 10;double batteryWidth = width() - headWidth;//绘制电池边框QPointF topLeft(5, 5);QPointF bottomRight(batteryWidth, height() - 5);batteryRect = QRectF(topLeft, bottomRight);painter->setPen(QPen(borderColorStart, 5));painter->setBrush(Qt::NoBrush);painter->drawRoundedRect(batteryRect, borderRadius, borderRadius);painter->restore();
}void Battery::drawBg(QPainter *painter)
{painter->save();QLinearGradient batteryGradient(QPointF(0, 0), QPointF(0, height()));if (currentValue <= alarmValue) {batteryGradient.setColorAt(0.0, alarmColorStart);batteryGradient.setColorAt(1.0, alarmColorEnd);} else {batteryGradient.setColorAt(0.0, normalColorStart);batteryGradient.setColorAt(1.0, normalColorEnd);}int margin = qMin(width(), height()) / 20;double unit = (batteryRect.width() - (margin * 2)) / 100;double width = currentValue * unit;QPointF topLeft(batteryRect.topLeft().x() + margin, batteryRect.topLeft().y() + margin);QPointF bottomRight(width + margin + 5, batteryRect.bottomRight().y() - margin);QRectF rect(topLeft, bottomRight);painter->setPen(Qt::NoPen);painter->setBrush(batteryGradient);painter->drawRoundedRect(rect, bgRadius, bgRadius);painter->restore();
}void Battery::drawHead(QPainter *painter)
{painter->save();QPointF headRectTopLeft(batteryRect.topRight().x(), height() / 3);QPointF headRectBottomRight(width(), height() - height() / 3);QRectF headRect(headRectTopLeft, headRectBottomRight);QLinearGradient headRectGradient(headRect.topLeft(), headRect.bottomLeft());headRectGradient.setColorAt(0.0, borderColorStart);headRectGradient.setColorAt(1.0, borderColorEnd);painter->setPen(Qt::NoPen);painter->setBrush(headRectGradient);painter->drawRoundedRect(headRect, headRadius, headRadius);painter->restore();
}