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// Copyright (C) 2023 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "legendwidget.h"
#include <QBarSet>
#include <QBarSeries>
#include <QChart>
#include <QChartView>
#include <QCheckBox>
#include <QDoubleSpinBox>
#include <QFormLayout>
#include <QGraphicsLayout>
#include <QGridLayout>
#include <QGroupBox>
#include <QLegend>
#include <QPushButton>
LegendWidget::LegendWidget(QWidget *parent)
: ContentWidget(parent)
{
// Create chart view with the chart
m_chart = new QChart;
m_chartView = new QChartView(m_chart, this);
m_chart->setTitle("Legend Options");
createUi();
connect(m_toggleAttachedButton, &QPushButton::clicked, this, &LegendWidget::toggleAttached);
connect(m_interactiveButton, &QPushButton::clicked, this, &LegendWidget::toggleInteractive);
connect(m_boldButton, &QPushButton::clicked, this, &LegendWidget::toggleBold);
connect(m_italicButton, &QPushButton::clicked, this, &LegendWidget::toggleItalic);
connect(m_addSetButton, &QPushButton::clicked, this, &LegendWidget::addBarset);
connect(m_removeSetButton, &QPushButton::clicked, this, &LegendWidget::removeBarset);
connect(m_alignmentButton, &QPushButton::clicked, this, &LegendWidget::setLegendAlignment);
connect(m_fontSize,
static_cast<void (QDoubleSpinBox::*)(double)>(&QDoubleSpinBox::valueChanged),
this, &LegendWidget::fontSizeChanged);
connect(m_legendPosX,
static_cast<void (QDoubleSpinBox::*)(double)>(&QDoubleSpinBox::valueChanged),
this, &LegendWidget::updateLegendLayout);
connect(m_legendPosY,
static_cast<void (QDoubleSpinBox::*)(double)>(&QDoubleSpinBox::valueChanged),
this, &LegendWidget::updateLegendLayout);
connect(m_legendWidth,
static_cast<void (QDoubleSpinBox::*)(double)>(&QDoubleSpinBox::valueChanged),
this, &LegendWidget::updateLegendLayout);
connect(m_legendHeight,
static_cast<void (QDoubleSpinBox::*)(double)>(&QDoubleSpinBox::valueChanged),
this, &LegendWidget::updateLegendLayout);
QLegend *legend = m_chart->legend();
legend->setShowToolTips(true);
legend->setBrush(QBrush(QColor(128, 128, 128, 128)));
legend->setPen(QPen(QColor(192, 192, 192, 192)));
//![5]
legend->setInteractive(true);
//![5]
//![4]
connect(legend, &QLegend::attachedToChartChanged, [legend, this](bool attachedToChart) {
m_toggleAttachedButton->setChecked(attachedToChart);
legend->setBackgroundVisible(!attachedToChart);
m_geometrySettings->setDisabled(attachedToChart);
});
//![4]
connect(legend, &QGraphicsWidget::geometryChanged, this, &LegendWidget::updateLegendSpinbox);
createSeries();
m_chart->createDefaultAxes();
//![1]
m_chart->legend()->setVisible(true);
m_chart->legend()->setAlignment(Qt::AlignBottom);
//![1]
m_chartView->setRenderHint(QPainter::Antialiasing);
m_chart->layout()->setContentsMargins(0, 0, 0, 0);
}
void LegendWidget::resizeEvent(QResizeEvent *)
{
QRectF chartViewRect = m_chartView->rect();
m_legendPosX->setMaximum(chartViewRect.width());
m_legendPosY->setMaximum(chartViewRect.height());
m_legendWidth->setMaximum(chartViewRect.width());
m_legendHeight->setMaximum(chartViewRect.height());
}
void LegendWidget::createUi()
{
QLegend *legend = m_chart->legend();
// Create buttons for ui
auto buttonLayout = new QGridLayout;
m_toggleAttachedButton = new QCheckBox("Attached", this);
m_toggleAttachedButton->setChecked(true);
buttonLayout->addWidget(m_toggleAttachedButton, 0, 0);
m_interactiveButton = new QCheckBox("Interactive", this);
m_interactiveButton->setChecked(true);
buttonLayout->addWidget(m_interactiveButton, 1, 0);
m_boldButton = new QCheckBox("Bold", this);
buttonLayout->addWidget(m_boldButton, 2, 0);
m_italicButton = new QCheckBox("Italic", this);
buttonLayout->addWidget(m_italicButton, 3, 0);
m_addSetButton = new QPushButton("Add Barset", this);
buttonLayout->addWidget(m_addSetButton, 4, 0);
m_removeSetButton = new QPushButton("Remove Barset", this);
buttonLayout->addWidget(m_removeSetButton, 5, 0);
m_alignmentButton = new QPushButton("Align (Bottom)", this);
buttonLayout->addWidget(m_alignmentButton, 6, 0);
buttonLayout->setRowStretch(7, 1);
m_legendPosX = new QDoubleSpinBox(this);
m_legendPosY = new QDoubleSpinBox(this);
m_legendWidth = new QDoubleSpinBox(this);
m_legendHeight = new QDoubleSpinBox(this);
auto legendLayout = new QFormLayout;
legendLayout->addRow("HPos", m_legendPosX);
legendLayout->addRow("VPos", m_legendPosY);
legendLayout->addRow("Width", m_legendWidth);
legendLayout->addRow("Height", m_legendHeight);
m_geometrySettings = new QGroupBox("Detached legend", this);
m_geometrySettings->setLayout(legendLayout);
buttonLayout->addWidget(m_geometrySettings, 8, 0);
m_geometrySettings->setDisabled(true);
// Create spinbox to modify font size
m_fontSize = new QDoubleSpinBox(this);
QFont lfont = legend->font();
lfont.setPointSizeF(12.0);
legend->setFont(lfont);
m_fontSize->setValue(legend->font().pointSizeF());
m_fontSize->setMinimum(1.);
auto fontLayout = new QFormLayout;
fontLayout->addRow("Legend font size", m_fontSize);
// Create layout for grid and detached legend
auto mainLayout = new QGridLayout;
mainLayout->setHorizontalSpacing(10);
mainLayout->addLayout(buttonLayout, 0, 0);
mainLayout->addLayout(fontLayout, 1, 0);
mainLayout->addWidget(m_chartView, 0, 1, 3, 1);
setLayout(mainLayout);
}
void LegendWidget::createSeries()
{
m_series = new QBarSeries;
addBarset();
addBarset();
addBarset();
addBarset();
m_chart->addSeries(m_series);
}
void LegendWidget::updateLegendSpinbox()
{
QLegend *legend = m_chart->legend();
double newPosX = legend->x();
double newPosY = legend->y();
QSizeF newSize = legend->size();
if (!qFuzzyCompare(m_legendPosX->value(), newPosX))
m_legendPosX->setValue(newPosX);
if (!qFuzzyCompare(m_legendPosY->value(), newPosY))
m_legendPosY->setValue(newPosY);
if (!qFuzzyCompare(m_legendWidth->value(), newSize.width()))
m_legendWidth->setValue(newSize.width());
if (!qFuzzyCompare(m_legendHeight->value(), newSize.height()))
m_legendHeight->setValue(newSize.height());
}
void LegendWidget::toggleAttached()
{
QLegend *legend = m_chart->legend();
if (legend->isAttachedToChart()) {
//![2]
legend->detachFromChart();
//![2]
} else {
//![3]
legend->attachToChart();
//![3]
}
update();
}
void LegendWidget::toggleInteractive()
{
m_chart->legend()->setInteractive(!m_chart->legend()->isInteractive());
}
void LegendWidget::toggleBold()
{
QFont font = m_chart->legend()->font();
font.setBold(!font.bold());
m_chart->legend()->setFont(font);
}
void LegendWidget::toggleItalic()
{
QFont font = m_chart->legend()->font();
font.setItalic(!font.italic());
m_chart->legend()->setFont(font);
}
void LegendWidget::addBarset()
{
auto barSet = new QBarSet(QString("set ") + QString::number(m_series->count()));
qreal delta = m_series->count() * 0.1;
*barSet << 1 + delta << 2 + delta << 3 + delta << 4 + delta;
m_series->append(barSet);
}
void LegendWidget::removeBarset()
{
QList<QBarSet *> sets = m_series->barSets();
if (sets.count() > 0) {
m_series->remove(sets.at(sets.count() - 1));
}
}
void LegendWidget::setLegendAlignment()
{
auto button = qobject_cast<QPushButton *>(sender());
switch (m_chart->legend()->alignment()) {
case Qt::AlignTop:
m_chart->legend()->setAlignment(Qt::AlignLeft);
if (button)
button->setText("Align (Left)");
break;
case Qt::AlignLeft:
m_chart->legend()->setAlignment(Qt::AlignBottom);
if (button)
button->setText("Align (Bottom)");
break;
case Qt::AlignBottom:
m_chart->legend()->setAlignment(Qt::AlignRight);
if (button)
button->setText("Align (Right)");
break;
default:
if (button)
button->setText("Align (Top)");
m_chart->legend()->setAlignment(Qt::AlignTop);
break;
}
}
void LegendWidget::fontSizeChanged()
{
QFont font = m_chart->legend()->font();
font.setPointSizeF(m_fontSize->value());
m_chart->legend()->setFont(font);
}
void LegendWidget::updateLegendLayout()
{
//![6]
QRectF geom = m_chart->legend()->geometry();
if (qFuzzyCompare(geom.x(), m_legendPosX->value())
&& qFuzzyCompare(geom.y(), m_legendPosY->value())
&& qFuzzyCompare(geom.width(), m_legendWidth->value())
&& qFuzzyCompare(geom.height(), m_legendHeight->value()))
return;
m_chart->legend()->setGeometry(QRectF(m_legendPosX->value(),
m_legendPosY->value(),
m_legendWidth->value(),
m_legendHeight->value()));
m_chart->legend()->update();
//![6]
}