QFD2/QFD/widgets/CustomPie.cpp

#include "CustomPie.h"

#include <QPainter>

CustomPie::CustomPie(QWidget *parent) : QWidget(parent) { }

CustomPie::~CustomPie() { }

void CustomPie::paintEvent(QPaintEvent *)
{
    int width  = this->width();
    int height = this->height();
    int side   = qMin(width, height);

    // 绘制准备工作,启用反锯齿,平移坐标轴中心,等比例缩放
    QPainter painter(this);
    painter.setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing);
    painter.translate(width / 2, height / 2);
    painter.scale(side / 200.0, side / 200.0);

    // 绘制饼图
    drawPie(&painter);
}

void CustomPie::drawPie(QPainter *painter)
{
    painter->save();

    int radius = 93;
    QRect rect(-radius, -radius, radius * 2, radius * 2);

    double startAngle = 0;
    double sum        = getSumValue();

    // 逐个取出值并绘制饼图区域和对应的文字
    int count = labels.count();
    for (int i = 0; i < count; ++i) {
        // 取出值并计算当前值占比面积
        double value     = values.at(i);
        double arcLength = value / sum * 360;
        double percent   = value / sum * 100;
        QRect pieRect    = rect;

        // 如果当前区域展开则需要设置边框
        painter->setPen(Qt::NoPen);
        if (explodedIndex == i || explodedAll) {
            painter->setPen(borderColor);
            QPoint center = pieRect.center();
            int mid       = startAngle + arcLength / 2;
            center += getOffsetPoint(mid);
            pieRect.moveCenter(center);
        }

        // 从颜色集合中取出颜色
        painter->setBrush(colors.at(i));
        painter->drawPie(pieRect, startAngle * 16, arcLength * 16);

        QString strValue = labels.at(i);
        if (showPercent && percent > 7) {
            strValue = QString("%1%2%3%")
                               .arg(strValue)
                               .arg(strValue.isEmpty() ? "" : "\n")
                               .arg(QString::number(percent, 'f', 0));
        }

        int mid    = startAngle + arcLength / 2;
        int offset = 60;
        if (percent >= 50) {
            offset = 45;
        } else if (percent >= 30) {
            offset = 55;
        } else if (percent >= 15) {
            offset = 60;
        }

        QPoint p = getOffsetPoint(mid, offset);
        QRect textRect;
        textRect.setX(p.x() - 40);
        textRect.setY(p.y() - 30);
        textRect.setWidth(80);
        textRect.setHeight(60);
        painter->setPen(Qt::black);
        // painter->drawRect(textRect);

        QFont font;
        font.setPixelSize(strValue.isEmpty() ? 20 : 17);
        painter->setFont(font);

        painter->setPen(textColor);
        painter->drawText(textRect, Qt::AlignCenter, strValue);
        startAngle += arcLength;
    }

    painter->restore();
}

double CustomPie::getSumValue()
{
    return labels.size();
}

QPoint CustomPie::getOffsetPoint(double angel, int offset)
{
    return QPoint {};
}

QColor CustomPie::getTextColor() const
{
    return textColor;
}

QColor CustomPie::getBorderColor() const
{
    return borderColor;
}

void CustomPie::setExplodedAll(bool explodedAll)
{
    this->explodedAll = explodedAll;
}

void CustomPie::setExplodedIndex(int index)
{
    this->explodedIndex = index;
}

void CustomPie::setDefaultColor(bool defaultColor)
{
    if (defaultColor) { }
}

void CustomPie::setTextColor(const QColor &textColor)
{
    this->textColor = textColor;
}

void CustomPie::setBorderColor(const QColor &borderColor)
{
    this->borderColor = borderColor;
}

void CustomPie::setColors(const QList<QColor> &colors)
{
    this->colors = colors;
}

void CustomPie::initPie() { }

void CustomPie::appendPie(const QString &label, double value, const QString &tip)
{
    labels.append(label);
    values.append(value);
}

void CustomPie::setDataPie() { }

void CustomPie::loadPercent() { }

void CustomPie::clearPie() { }

void CustomPie::setHoleSize(double holeSize) { }