graphgallery example: Rearrange initialization

Calculate the sizes in main and pass them to the graph initialization
functions. Also display the message box for GL errors in main.

Pick-to: 6.5
Task-number: QTBUG-110698
Change-Id: I622311220e6ff63980b59778bfe9bb56922e6149
Reviewed-by: Tomi Korpipää <tomi.korpipaa@qt.io>

7 files changed, 33 insertions, 46 deletions

diff --git a/examples/datavisualization/graphgallery/bargraph.cpp b/examples/datavisualization/graphgallery/bargraph.cpp
index 5bb04c01..3b981f87 100644
--- a/examples/datavisualization/graphgallery/bargraph.cpp
+++ b/examples/datavisualization/graphgallery/bargraph.cpp
@@ -10,7 +10,6 @@
 #include <QtWidgets/qslider.h>
 #include <QtWidgets/qfontcombobox.h>
 #include <QtWidgets/qlabel.h>
-#include <QtWidgets/qmessagebox.h>
 #include <QtWidgets/qradiobutton.h>
 #include <QtWidgets/qbuttongroup.h>
 #include <QtGui/qfontdatabase.h>
@@ -26,22 +25,18 @@ BarGraph::BarGraph()
 
 BarGraph::~BarGraph() = default;
 
-bool BarGraph::initialize()
+bool BarGraph::initialize(const QSize &minimumGraphSize, const QSize &maximumGraphSize)
 {
-    if (!m_barsGraph->hasContext()) {
-        QMessageBox msgBox;
-        msgBox.setText("Couldn't initialize the OpenGL context.");
-        msgBox.exec();
+    if (!m_barsGraph->hasContext())
         return false;
-    }
 
     //! [1]
     m_barsWidget = new QWidget;
     QHBoxLayout *hLayout = new QHBoxLayout(m_barsWidget);
     m_container = QWidget::createWindowContainer(m_barsGraph, m_barsWidget);
-    QSize screenSize = m_barsGraph->screen()->size();
-    m_container->setMinimumSize(QSize(screenSize.width() / 2, screenSize.height() / 1.75));
-    m_container->setMaximumSize(screenSize);
+    m_barsGraph->resize(minimumGraphSize);
+    m_container->setMinimumSize(minimumGraphSize);
+    m_container->setMaximumSize(maximumGraphSize);
     m_container->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
     m_container->setFocusPolicy(Qt::StrongFocus);
     hLayout->addWidget(m_container, 1);
diff --git a/examples/datavisualization/graphgallery/bargraph.h b/examples/datavisualization/graphgallery/bargraph.h
index 79c78510..5c4f98d9 100644
--- a/examples/datavisualization/graphgallery/bargraph.h
+++ b/examples/datavisualization/graphgallery/bargraph.h
@@ -14,7 +14,7 @@ public:
     BarGraph();
     ~BarGraph();
 
-    bool initialize();
+    bool initialize(const QSize &minimumGraphSize, const QSize &maximumGraphSize);
     QWidget *barsWidget() { return m_barsWidget; }
 
 private:
diff --git a/examples/datavisualization/graphgallery/main.cpp b/examples/datavisualization/graphgallery/main.cpp
index efe8ecbd..3e581983 100644
--- a/examples/datavisualization/graphgallery/main.cpp
+++ b/examples/datavisualization/graphgallery/main.cpp
@@ -6,8 +6,10 @@
 #include "surfacegraph.h"
 
 #include <QtWidgets/qapplication.h>
+#include <QtWidgets/qmessagebox.h>
 #include <QtWidgets/qwidget.h>
 #include <QtWidgets/qtabwidget.h>
+#include <QtGui/qscreen.h>
 
 using namespace Qt::StringLiterals;
 
@@ -17,24 +19,26 @@ int main(int argc, char **argv)
 
     QApplication app(argc, argv);
 
+    // Create a tab widget for creating own tabs for Q3DBars, Q3DScatter, and Q3DSurface
+    QTabWidget tabWidget;
+    tabWidget.setWindowTitle(u"Graph Gallery"_s);
+
+    const QSize screenSize = tabWidget.screen()->size();
+    const QSize minimumGraphSize{screenSize.width() / 2, qRound(screenSize.height() / 1.75)};
+
     // Create bar graph
     BarGraph bars;
-    if (!bars.initialize())
-        return -1;
-
     // Create scatter graph
     ScatterGraph scatter;
-    if (!scatter.initialize())
-        return -1;
-
     // Create surface graph
     SurfaceGraph surface;
-    if (!surface.initialize())
-        return -1;
 
-    // Create a tab widget for creating own tabs for Q3DBars, Q3DScatter, and Q3DSurface
-    QTabWidget tabWidget;
-    tabWidget.setWindowTitle(u"Graph Gallery"_s);
+    if (!bars.initialize(minimumGraphSize, screenSize)
+        || !scatter.initialize(minimumGraphSize, screenSize)
+        || !surface.initialize(minimumGraphSize, screenSize)) {
+        QMessageBox::warning(nullptr, u"Graph Gallery"_s, u"Couldn't initialize the OpenGL context."_s);
+        return -1;
+    }
 
     // Add bars widget
     tabWidget.addTab(bars.barsWidget(), u"Bar Graph"_s);
diff --git a/examples/datavisualization/graphgallery/scattergraph.cpp b/examples/datavisualization/graphgallery/scattergraph.cpp
index 043d43ac..7506f914 100644
--- a/examples/datavisualization/graphgallery/scattergraph.cpp
+++ b/examples/datavisualization/graphgallery/scattergraph.cpp
@@ -8,7 +8,6 @@
 #include <QtWidgets/qcheckbox.h>
 #include <QtWidgets/qcombobox.h>
 #include <QtWidgets/qlabel.h>
-#include <QtWidgets/qmessagebox.h>
 #include <QtWidgets/qcommandlinkbutton.h>
 
 using namespace Qt::StringLiterals;
@@ -20,21 +19,16 @@ ScatterGraph::ScatterGraph()
 
 ScatterGraph::~ScatterGraph() = default;
 
-bool ScatterGraph::initialize()
+bool ScatterGraph::initialize(const QSize &minimumGraphSize, const QSize &maximumGraphSize)
 {
-    if (!m_scatterGraph->hasContext()) {
-        QMessageBox msgBox;
-        msgBox.setText("Couldn't initialize the OpenGL context.");
-        msgBox.exec();
-        return -1;
-    }
+    if (!m_scatterGraph->hasContext())
+        return false;
 
     m_scatterWidget = new QWidget;
     QHBoxLayout *hLayout = new QHBoxLayout(m_scatterWidget);
     m_container = QWidget::createWindowContainer(m_scatterGraph, m_scatterWidget);
-    QSize screenSize = m_scatterGraph->screen()->size();
-    m_container->setMinimumSize(QSize(screenSize.width() / 2, screenSize.height() / 1.75));
-    m_container->setMaximumSize(screenSize);
+    m_container->setMinimumSize(minimumGraphSize);
+    m_container->setMaximumSize(maximumGraphSize);
     m_container->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
     m_container->setFocusPolicy(Qt::StrongFocus);
     hLayout->addWidget(m_container, 1);
diff --git a/examples/datavisualization/graphgallery/scattergraph.h b/examples/datavisualization/graphgallery/scattergraph.h
index 0d3b8fc3..a7170eee 100644
--- a/examples/datavisualization/graphgallery/scattergraph.h
+++ b/examples/datavisualization/graphgallery/scattergraph.h
@@ -14,7 +14,7 @@ public:
     ScatterGraph();
     ~ScatterGraph();
 
-    bool initialize();
+    bool initialize(const QSize &minimumGraphSize, const QSize &maximumGraphSize);
     QWidget *scatterWidget() { return m_scatterWidget; }
 
 private:
diff --git a/examples/datavisualization/graphgallery/surfacegraph.cpp b/examples/datavisualization/graphgallery/surfacegraph.cpp
index 5de2b7cd..6147c437 100644
--- a/examples/datavisualization/graphgallery/surfacegraph.cpp
+++ b/examples/datavisualization/graphgallery/surfacegraph.cpp
@@ -10,7 +10,6 @@
 #include <QtWidgets/qradiobutton.h>
 #include <QtWidgets/qgroupbox.h>
 #include <QtWidgets/qlabel.h>
-#include <QtWidgets/qmessagebox.h>
 #include <QtWidgets/qcommandlinkbutton.h>
 #include <QtGui/qpainter.h>
 
@@ -23,21 +22,16 @@ SurfaceGraph::SurfaceGraph()
 
 SurfaceGraph::~SurfaceGraph() = default;
 
-bool SurfaceGraph::initialize()
+bool SurfaceGraph::initialize(const QSize &minimumGraphSize, const QSize &maximumGraphSize)
 {
-    if (!m_surfaceGraph->hasContext()) {
-        QMessageBox msgBox;
-        msgBox.setText("Couldn't initialize the OpenGL context.");
-        msgBox.exec();
-        return -1;
-    }
+    if (!m_surfaceGraph->hasContext())
+        return false;
 
     m_surfaceWidget = new QWidget;
     QHBoxLayout *hLayout = new QHBoxLayout(m_surfaceWidget);
     m_container = QWidget::createWindowContainer(m_surfaceGraph, m_surfaceWidget);
-    QSize screenSize = m_surfaceGraph->screen()->size();
-    m_container->setMinimumSize(QSize(screenSize.width() / 2, screenSize.height() / 1.75));
-    m_container->setMaximumSize(screenSize);
+    m_container->setMinimumSize(minimumGraphSize);
+    m_container->setMaximumSize(maximumGraphSize);
     m_container->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
     m_container->setFocusPolicy(Qt::StrongFocus);
     hLayout->addWidget(m_container, 1);
diff --git a/examples/datavisualization/graphgallery/surfacegraph.h b/examples/datavisualization/graphgallery/surfacegraph.h
index 92b448ad..5e012b19 100644
--- a/examples/datavisualization/graphgallery/surfacegraph.h
+++ b/examples/datavisualization/graphgallery/surfacegraph.h
@@ -14,7 +14,7 @@ public:
     SurfaceGraph();
     ~SurfaceGraph();
 
-    bool initialize();
+    bool initialize(const QSize &minimumGraphSize, const QSize &maximumGraphSize);
     QWidget *surfaceWidget() { return m_surfaceWidget; }
 
 private: