cpp
复制代码
#include <QtGui>
#include <QColor>
#include <cstdlib>
#include <cassert>
#include <numeric>
#include <chartwork/PieChart.h>
#include <chartwork/Design.h>
#include <chartwork/exceptions/OutOfRangeException.h>
#include <chartwork/exceptions/EmptyException.h>
#include <chartwork/exceptions/UnknownItemException.h>
namespace chartwork
{
//
// PieChart
//
PieChart::PieChart(QWidget *parent)
: Chart(parent),
m_fontMetrics(m_font),
m_showPercentage(true),
m_precision(1),
m_labels(std::shared_ptr<QStringList>(new QStringList({"A", "B", "C", "D"}))),
m_key(m_labels, m_colors)
{
setWindowTitle(tr("Pie Chart"));
resize(400, 300);
setMinimumSize(200, 150);
generateRandomValues();
m_title.setText("Pie Chart");
update();
}
const QStringList &PieChart::labels() const
{
return *m_labels;
}
void PieChart::setLabels(const QStringList &labels)
{
*m_labels = labels;
m_key.updateSize();
generateRandomValues();
update();
}
bool PieChart::showKey() const
{
return m_key.isVisible();
}
void PieChart::setShowKey(bool showKey)
{
m_key.setVisible(showKey);
update();
}
double PieChart::keyScale() const
{
return m_key.scale();
}
void PieChart::setKeyScale(double keyScale)
{
m_key.setScale(keyScale);
update();
}
bool PieChart::showPercentage() const
{
return m_showPercentage;
}
void PieChart::setShowPercentage(bool showPercentage)
{
m_showPercentage = showPercentage;
update();
}
int PieChart::precision() const
{
return m_precision;
}
void PieChart::setPrecision(int precision)
{
m_precision = std::max(0, precision);
update();
}
void PieChart::resetValues()
{
m_values.clear();
m_values.resize(m_labels->size(), 0.0);
}
void PieChart::generateRandomValues()
{
resetValues();
std::srand(0);
for (int i = 0; i < m_labels->size(); i++)
m_values[i] = std::rand() / (double)RAND_MAX * 100;
}
double PieChart::diameter(int remainingWidth, int remainingHeight) const
{
return std::max(0.0, std::min((double)remainingWidth, (double)remainingHeight));
}
void PieChart::paintEvent(QPaintEvent *)
{
if (m_labels->empty())
return;
if (m_values.size() < (size_t)m_labels->size())
return;
m_title.setWidth(width());
m_title.moveTopLeft(QPoint(0, design::spacing - m_title.rect().height() / 4));
int remainingWidth = width() - m_key.rect().width() - 3 * design::spacing;
if (!m_key.isVisible())
remainingWidth += design::spacing;
const int remainingHeight = height() - m_title.rect().height() - 2 * design::spacing;
m_diameter = diameter(remainingWidth, remainingHeight);
m_chartRect.setSize(QSize(m_diameter, m_diameter));
const int outerSpacing = (remainingWidth - m_diameter) / 2;
m_chartRect.moveLeft(design::spacing + outerSpacing);
m_chartRect.moveTop(design::spacing + m_title.rect().height() + (remainingHeight - m_diameter) / 2);
m_key.moveTopRight(QPoint(m_chartRect.left() + m_chartRect.width() + design::spacing + m_key.rect().width(), design::spacing + m_title.rect().height() + (remainingHeight - m_key.rect().height()) / 2));
QPainter painter(this);
m_background.paint(painter);
m_title.paint(painter);
paint(painter);
m_key.paint(painter);
}
void PieChart::paint(QPainter &painter)
{
const double sumOfValues = std::accumulate(m_values.begin(),
m_values.end(), 0.0, [](double sum, double v){return sum + std::max(0.0, v);});
painter.setRenderHint(QPainter::Antialiasing);
double currentAngle = 0;
for (size_t i = 0; i < m_values.size(); i++)
{
const double angleValue = m_values[i] / sumOfValues * 360 * 16;
if (angleValue <= 0.0)
continue;
const QColor &color = (*m_colors)[i % m_colors->size()];
painter.setBrush(color);
painter.drawPie(m_chartRect, std::round(-currentAngle + 90 * 16 - angleValue), std::round(angleValue));
currentAngle += angleValue;
}
painter.setRenderHint(QPainter::Antialiasing,false);
if (!m_showPercentage)
return;
currentAngle = 0;
for (size_t i = 0; i < m_values.size(); i++)
{
const double angleValue = m_values[i] / sumOfValues * 2.0 * M_PI;
if (angleValue <= 0.0)
continue;
const double midAngle = -currentAngle + M_PI_2 - angleValue / 2.0f;
painter.setPen(Qt::SolidLine);
painter.setFont(m_font);
const QColor &color = (*m_colors)[i % m_colors->size()];
if (color.value() < 210)
painter.setPen(design::superlightgray);
const QString percentageText = QString("%1").arg(m_values[i] / sumOfValues * 100.0, 0, 'f', m_precision) + QString(" %");
const QPoint textCenter = m_chartRect.center() + QPoint(m_diameter / 3 * std::cos(midAngle), -m_diameter / 3 * std::sin(midAngle));
const double textWidth = m_fontMetrics.width(percentageText) + 24;
const double textHeight = m_fontMetrics.height() + 24;
painter.drawText(QRect(textCenter.x() - textWidth / 2,
textCenter.y() - textHeight / 2,
textWidth,
textHeight),
percentageText, QTextOption(Qt::AlignCenter));
painter.setPen(Qt::NoPen);
currentAngle += angleValue;
}
}
void PieChart::setValue(int slice, double value)
{
handleValueUpdate();
if (m_values.empty())
throw exceptions::EmptyException("PieChart", objectName(), "labels");
if (slice < 0 || (size_t)slice >= m_values.size())
throw exceptions::OutOfRangeException("PieChart", objectName(), "slice", slice, 0, (int)m_values.size() - 1);
m_values[slice] = value;
}
void PieChart::setValue(const QString &label, double value)
{
if (m_values.empty())
throw exceptions::EmptyException("PieChart", objectName(), "labels");
const int sliceIndex = m_labels->indexOf(label);
if (sliceIndex < 0)
throw exceptions::UnknownItemException("PieChart", objectName(), "label", label, *m_labels);
setValue(sliceIndex, value);
}
void PieChart::setAllValues(double value)
{
handleValueUpdate();
m_values.clear();
m_values.resize(m_labels->size(), value);
}
double PieChart::value(int slice) const
{
if (m_values.empty())
throw exceptions::EmptyException("PieChart", objectName(), "labels");
if (slice < 0 || (size_t)slice >= m_values.size())
throw exceptions::OutOfRangeException("PieChart", objectName(), "slice", slice, 0, (int)m_values.size() - 1);
return m_values[slice];
}
double PieChart::value(const QString &label) const
{
if (m_values.empty())
throw exceptions::EmptyException("PieChart", objectName(), "labels");
const int sliceIndex = m_labels->indexOf(label);
if (sliceIndex < 0)
throw exceptions::UnknownItemException("PieChart", objectName(), "label", label, *m_labels);
return value(sliceIndex);
}
}
