Qt wifi控件绘制

绘制方法：

  QPainter painter(this);
    painter.save();
    painter.setPen(Qt::NoPen);
    QLinearGradient bgGradient(QPointF(0, 0), QPointF(0, height()));
    bgGradient.setColorAt(0.0, QColor(0, 0, 0));
    bgGradient.setColorAt(1.0, QColor(0, 0, 0));
    painter.setBrush(bgGradient);
    painter.drawRect(rect());
    painter.restore();
    painter.translate(width()/2, height()*0.85);
    painter.setRenderHint(QPainter::Antialiasing, true);
//绘制背景条
    gradientArc(&painter, radius*0.8, 45, 90, arcHeight, qRgb(54, 54, 54));
    gradientArc(&painter, radius*0.6, 45, 90, arcHeight, qRgb(54, 54, 54));
    gradientArc(&painter, radius*0.4, 45, 90, arcHeight, qRgb(54, 54, 54));
    gradientArc(&painter, radius*0.2, 45, 90, arcHeight, qRgb(54, 54, 54));

    if(wifiQuality == 0){

    }else if(wifiQuality == 1)
    {
        gradientArc(&painter, radius*0.2, 45, 90, arcHeight, qRgb(255, 255, 255));
    }else if(wifiQuality == 2)
    {
        gradientArc(&painter, radius*0.4, 45, 90, arcHeight, qRgb(255, 255, 255));
        gradientArc(&painter, radius*0.2, 45, 90, arcHeight, qRgb(255, 255, 255));
    }else if(wifiQuality == 3)
    {
        gradientArc(&painter, radius*0.6, 45, 90, arcHeight, qRgb(255, 255, 255));
        gradientArc(&painter, radius*0.4, 45, 90, arcHeight, qRgb(255, 255, 255));
        gradientArc(&painter, radius*0.2, 45, 90, arcHeight, qRgb(255, 255, 255));
    }else if(wifiQuality == 4)
    {
        gradientArc(&painter, radius*0.8, 45, 90, arcHeight, qRgb(255, 255, 255));
        gradientArc(&painter, radius*0.6, 45, 90, arcHeight, qRgb(255, 255, 255));
        gradientArc(&painter, radius*0.4, 45, 90, arcHeight, qRgb(255, 255, 255));
        gradientArc(&painter, radius*0.2, 45, 90, arcHeight, qRgb(255, 255, 255));
    }

    painter.translate(0, height()*0.05);
    painter.setBrush(QColor(255, 255, 255));
    painter.drawEllipse(QPointF(0,0),arcLength,arcLength);