Add bar chart example

Example shows using setBarSelected().
Selecting bars changes their color and information of selected/unselected bars.
[QtCharts][Example] Added Example

Task-number: QTBUG-89445
Change-Id: Ic863e763d2cfa552629f42afd1232c1f77b95e95
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@qt.io>
(cherry picked from commit 72d69b22d8da004fcb27e1a549cdda3f52b9c4af)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

7 files changed, 319 insertions, 1 deletions

diff --git a/examples/charts/CMakeLists.txt b/examples/charts/CMakeLists.txt
index 8cd0211f..a2122782 100644
--- a/examples/charts/CMakeLists.txt
+++ b/examples/charts/CMakeLists.txt
@@ -34,6 +34,7 @@ if(QT_FEATURE_charts_bar_chart)
     add_subdirectory(percentbarchart)
     add_subdirectory(legend)
     add_subdirectory(temperaturerecords)
+    add_subdirectory(selectedbar)
 endif()
 if(QT_FEATURE_charts_pie_chart)
     add_subdirectory(donutchart)
diff --git a/examples/charts/charts.pro b/examples/charts/charts.pro
index 1e60be5a..cd92cfe2 100644
--- a/examples/charts/charts.pro
+++ b/examples/charts/charts.pro
@@ -39,7 +39,8 @@ qtConfig(charts-bar-chart) {
         stackedbarchartdrilldown \
         percentbarchart \
         legend \
-        temperaturerecords
+        temperaturerecords \
+        selectedbar
 }
 qtConfig(charts-pie-chart) {
     SUBDIRS += \
diff --git a/examples/charts/selectedbar/CMakeLists.txt b/examples/charts/selectedbar/CMakeLists.txt
new file mode 100644
index 00000000..55542a42
--- /dev/null
+++ b/examples/charts/selectedbar/CMakeLists.txt
@@ -0,0 +1,40 @@
+# Generated from selectedbar.pro.
+
+cmake_minimum_required(VERSION 3.14)
+project(selectedbar LANGUAGES CXX)
+
+set(CMAKE_INCLUDE_CURRENT_DIR ON)
+
+set(CMAKE_AUTOMOC ON)
+set(CMAKE_AUTORCC ON)
+set(CMAKE_AUTOUIC ON)
+
+if(NOT DEFINED INSTALL_EXAMPLESDIR)
+  set(INSTALL_EXAMPLESDIR "examples")
+endif()
+
+set(INSTALL_EXAMPLEDIR "${INSTALL_EXAMPLESDIR}/charts/selectedbar")
+
+find_package(Qt6 COMPONENTS Core)
+find_package(Qt6 COMPONENTS Gui)
+find_package(Qt6 COMPONENTS Charts)
+
+qt_add_executable(selectedbar
+    utilities.h utilities.cpp
+    main.cpp
+)
+set_target_properties(selectedbar PROPERTIES
+    WIN32_EXECUTABLE TRUE
+    MACOSX_BUNDLE TRUE
+)
+target_link_libraries(selectedbar PUBLIC
+    Qt::Charts
+    Qt::Core
+    Qt::Gui
+)
+
+install(TARGETS selectedbar
+    RUNTIME DESTINATION "${INSTALL_EXAMPLEDIR}"
+    BUNDLE DESTINATION "${INSTALL_EXAMPLEDIR}"
+    LIBRARY DESTINATION "${INSTALL_EXAMPLEDIR}"
+)
diff --git a/examples/charts/selectedbar/main.cpp b/examples/charts/selectedbar/main.cpp
new file mode 100644
index 00000000..9ed62441
--- /dev/null
+++ b/examples/charts/selectedbar/main.cpp
@@ -0,0 +1,146 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt Charts module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 or (at your option) any later version
+** approved by the KDE Free Qt Foundation. The licenses are as published by
+** the Free Software Foundation and appearing in the file LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "utilities.h"
+#include <QBarSet>
+#include <QApplication>
+#include <QBarSeries>
+#include <QList>
+#include <QChart>
+#include <QBarCategoryAxis>
+#include <QValueAxis>
+#include <QChartView>
+#include <QWindow>
+#include <QHBoxLayout>
+#include <QLabel>
+#include <QMainWindow>
+
+int main(int argc, char *argv[])
+{
+    QApplication a(argc, argv);
+    QMainWindow mainWindow;
+    mainWindow.setWindowTitle(QCoreApplication::tr("Meat consumption series"));
+
+    //![1]
+    QBarSet *setChicken = Utilities::createChickenSet();
+    QBarSet *setPork = Utilities::createPorkSet();
+    QBarSet *setTurkey = Utilities::createTurkeySet();
+    QBarSet *setHam = Utilities::createHamSet();
+    qreal totalSum = setChicken->sum() + setPork->sum() + setTurkey->sum() + setHam->sum();
+    QList<QBarSet *> setList = QList<QBarSet *>{setChicken, setPork, setTurkey, setHam};
+
+    QBarSeries *series = new QBarSeries();
+    series->append(setList);
+    //![1]
+
+    //![2]
+    QChart *chart = new QChart();
+    chart->addSeries(series);
+    chart->setTitle(QCoreApplication::tr("Meat consumption"));
+    chart->setAnimationOptions(QChart::SeriesAnimations);
+    chart->legend()->setVisible(true);
+    chart->legend()->setAlignment(Qt::AlignBottom);
+    //![2]
+
+    //![3]
+    for (QBarSet *barSet : series->barSets())
+        barSet->setSelectedColor(barSet->brush().color().darker());
+    //![3]
+
+    //![4]
+    QStringList categories = Utilities::createYearCategories();
+    QBarCategoryAxis *axisX = new QBarCategoryAxis();
+    axisX->setCategories(categories);
+    chart->addAxis(axisX, Qt::AlignBottom);
+    series->attachAxis(axisX);
+
+    QValueAxis *axisY = new QValueAxis();
+    axisY->setRange(0, 20);
+    axisY->setTitleText(QCoreApplication::tr("Tons"));
+    axisY->setLabelsAngle(-90);
+    axisY->setTitleVisible(true);
+    chart->addAxis(axisY, Qt::AlignLeft);
+    series->attachAxis(axisY);
+    //![4]
+
+    //![5]
+    QChartView *chartView = new QChartView(chart);
+    chartView->setRenderHint(QPainter::Antialiasing);
+    //![5]
+
+    //![6]
+    QWidget *labelWidget = new QWidget(&mainWindow);
+    QHBoxLayout *labelLayout = new QHBoxLayout(labelWidget);
+    labelLayout->setAlignment(Qt::AlignCenter);
+
+    QLabel *totalSumLabel = new QLabel(QCoreApplication::tr("Total sum: %1 T").arg(totalSum));
+    labelLayout->addWidget(totalSumLabel);
+    totalSumLabel->setContentsMargins(0, 0, 54, 0);
+
+    QLabel *selectedSumLabel = new QLabel(QCoreApplication::tr("Selected sum: 0 T"));
+    labelLayout->addWidget(selectedSumLabel);
+
+    QLabel *unselectedSumLabel = new QLabel(QCoreApplication::tr("Unselected sum: %1 T").arg(totalSum));
+    labelLayout->addWidget(unselectedSumLabel);
+    unselectedSumLabel->setContentsMargins(54, 0, 0, 0);
+    //![6]
+
+    //![7]
+    QObject::connect(series, &QAbstractBarSeries::clicked, series, [=](int index, QBarSet *set) {
+        set->toggleSelection({index});
+        qreal selectedSum = 0.;
+        for (int i = 0; i < setList.size(); ++i) {
+            auto selectedIndices = setList.at(i)->selectedBars();
+            for (int k = 0; k < selectedIndices.size(); ++k)
+                selectedSum += setList.at(i)->at(selectedIndices.at(k));
+        }
+        selectedSumLabel->setText(QCoreApplication::tr("Selected sum: %1 T").arg(selectedSum));
+        // Because of rounding errors, selectedSum can result in being bigger than total sum
+        qreal unselectedSum = totalSum - selectedSum < 0 ? 0. : totalSum - selectedSum;
+        unselectedSumLabel->setText(
+                                    QCoreApplication::tr("Unselected sum: %1 T")
+                                    .arg(unselectedSum)
+                                   );
+    });
+    //![7]
+
+    //![8]
+    QWidget *mainWidget = new QWidget(&mainWindow);
+    QVBoxLayout *mainLayout = new QVBoxLayout(mainWidget);
+
+    mainLayout->addWidget(chartView);
+    mainLayout->addWidget(labelWidget);
+
+    mainWindow.setCentralWidget(mainWidget);
+    mainWindow.resize(800, 600);
+
+    mainWindow.show();
+    return a.exec();
+    //![8]
+}
diff --git a/examples/charts/selectedbar/selectedbar.pro b/examples/charts/selectedbar/selectedbar.pro
new file mode 100644
index 00000000..24d0de08
--- /dev/null
+++ b/examples/charts/selectedbar/selectedbar.pro
@@ -0,0 +1,11 @@
+QT += charts widgets
+
+SOURCES += \
+    main.cpp \
+    utilities.cpp
+
+HEADERS += \
+    utilities.h
+
+target.path = $$[QT_INSTALL_EXAMPLES]/charts/selectedbar
+INSTALLS += target
diff --git a/examples/charts/selectedbar/utilities.cpp b/examples/charts/selectedbar/utilities.cpp
new file mode 100644
index 00000000..4bbf2c74
--- /dev/null
+++ b/examples/charts/selectedbar/utilities.cpp
@@ -0,0 +1,73 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt Charts module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 or (at your option) any later version
+** approved by the KDE Free Qt Foundation. The licenses are as published by
+** the Free Software Foundation and appearing in the file LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "utilities.h"
+#include <QCoreApplication>
+
+namespace Utilities
+{
+
+QBarSet *createChickenSet()
+{
+    QBarSet *set = new QBarSet(QCoreApplication::tr("Chicken"));
+    set->append({15.0, 12.0, 8.0, 11.5, 13.7});
+    return set;
+}
+
+QBarSet *createPorkSet()
+{
+    QBarSet *set = new QBarSet(QCoreApplication::tr("Pork"));
+    set->append({9.0, 11.0, 9.0, 7, 12.2});
+    return set;
+}
+
+QBarSet *createTurkeySet()
+{
+    QBarSet *set = new QBarSet(QCoreApplication::tr("Turkey"));
+    set->append({5.0, 7.6, 9.3, 8, 8.1});
+    return set;
+}
+
+QBarSet *createHamSet()
+{
+    QBarSet *set = new QBarSet(QCoreApplication::tr("Ham"));
+    set->append({5.4, 7.1, 9.3, 12.3, 11.3});
+    return set;
+}
+
+QStringList createYearCategories()
+{
+    return QStringList{QCoreApplication::tr("2017"),
+                       QCoreApplication::tr("2018"),
+                       QCoreApplication::tr("2019"),
+                       QCoreApplication::tr("2020"),
+                       QCoreApplication::tr("2021")};
+}
+
+}
diff --git a/examples/charts/selectedbar/utilities.h b/examples/charts/selectedbar/utilities.h
new file mode 100644
index 00000000..41fe9610
--- /dev/null
+++ b/examples/charts/selectedbar/utilities.h
@@ -0,0 +1,46 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt Charts module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 or (at your option) any later version
+** approved by the KDE Free Qt Foundation. The licenses are as published by
+** the Free Software Foundation and appearing in the file LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef UTILITIES_H
+#define UTILITIES_H
+
+#include <QList>
+#include <QBarSet>
+
+namespace Utilities
+{
+    QBarSet *createChickenSet();
+    QBarSet *createPorkSet();
+    QBarSet *createTurkeySet();
+    QBarSet *createHamSet();
+    QStringList createYearCategories();
+    qreal totalSum(const QList<QBarSet *> &setList);
+}
+
+#endif // UTILITIES_H