graphgallery example: Create the window containers with a parent

This avoids the QWindow being created as a top level window with a frame.

Pick-to: 6.5
Task-number: QTBUG-110698
Change-Id: I0a1116f833dd61c43a113c0e7a74a5181c1ee9b9
Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io>
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>

4 files changed, 24 insertions, 30 deletions

diff --git a/examples/datavisualization/graphgallery/bargraph.cpp b/examples/datavisualization/graphgallery/bargraph.cpp
index bdbd03a2..fcef6286 100644
--- a/examples/datavisualization/graphgallery/bargraph.cpp
+++ b/examples/datavisualization/graphgallery/bargraph.cpp
@@ -21,14 +21,10 @@ BarGraph::BarGraph()
 {
     //! [0]
     m_barsGraph = new Q3DBars();
-    m_container = QWidget::createWindowContainer(m_barsGraph);
     //! [0]
 }
 
-BarGraph::~BarGraph()
-{
-    delete m_container;
-}
+BarGraph::~BarGraph() = default;
 
 bool BarGraph::initialize()
 {
@@ -39,17 +35,18 @@ bool BarGraph::initialize()
         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_container->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
     m_container->setFocusPolicy(Qt::StrongFocus);
+    hLayout->addWidget(m_container, 1);
 
-    //! [1]
-    m_barsWidget = new QWidget;
-    QHBoxLayout *hLayout = new QHBoxLayout(m_barsWidget);
     QVBoxLayout *vLayout = new QVBoxLayout();
-    hLayout->addWidget(m_container, 1);
     hLayout->addLayout(vLayout);
     //! [1]
 
diff --git a/examples/datavisualization/graphgallery/doc/src/graphgallery.qdoc b/examples/datavisualization/graphgallery/doc/src/graphgallery.qdoc
index aca8c1a7..c4fdd854 100644
--- a/examples/datavisualization/graphgallery/doc/src/graphgallery.qdoc
+++ b/examples/datavisualization/graphgallery/doc/src/graphgallery.qdoc
@@ -34,15 +34,18 @@
 
     \section2 Creating the Application
 
-    First, in \c{bargraph.cpp}, instantiate Q3DBars and a window container for it:
+    First, in \c{bargraph.cpp}, instantiate Q3DBars:
 
     \snippet graphgallery/bargraph.cpp 0
 
-    The call to QWidget::createWindowContainer is required, as all data visualization graph classes
-    (Q3DBars, Q3DScatter, Q3DSurface) inherit QWindow. This is the only way to use a class that
-    inherits QWindow as a widget.
+    Then, create the widget, and horizontal and vertical layouts.
 
-    Then, create horizontal and vertical layouts. Add the graph and the vertical layout to the
+    The graph is embedded in a window container using
+    QWidget::createWindowContainer(). This is required because all data
+    visualization graph classes (Q3DBars, Q3DScatter, Q3DSurface) inherit
+    QWindow. This is the only way to use a class inheriting QWindow as a widget.
+
+    Add the graph and the vertical layout to the
     horizontal one:
 
     \snippet graphgallery/bargraph.cpp 1
diff --git a/examples/datavisualization/graphgallery/scattergraph.cpp b/examples/datavisualization/graphgallery/scattergraph.cpp
index baab4663..cbcc082b 100644
--- a/examples/datavisualization/graphgallery/scattergraph.cpp
+++ b/examples/datavisualization/graphgallery/scattergraph.cpp
@@ -16,13 +16,9 @@ using namespace Qt::StringLiterals;
 ScatterGraph::ScatterGraph()
 {
     m_scatterGraph = new Q3DScatter();
-    m_container = QWidget::createWindowContainer(m_scatterGraph);
 }
 
-ScatterGraph::~ScatterGraph()
-{
-    delete m_container;
-}
+ScatterGraph::~ScatterGraph() = default;
 
 bool ScatterGraph::initialize()
 {
@@ -33,16 +29,17 @@ bool ScatterGraph::initialize()
         return -1;
     }
 
+    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->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
     m_container->setFocusPolicy(Qt::StrongFocus);
+    hLayout->addWidget(m_container, 1);
 
-    m_scatterWidget = new QWidget;
-    QHBoxLayout *hLayout = new QHBoxLayout(m_scatterWidget);
     QVBoxLayout *vLayout = new QVBoxLayout();
-    hLayout->addWidget(m_container, 1);
     hLayout->addLayout(vLayout);
 
     QCommandLinkButton *cameraButton = new QCommandLinkButton(m_scatterWidget);
diff --git a/examples/datavisualization/graphgallery/surfacegraph.cpp b/examples/datavisualization/graphgallery/surfacegraph.cpp
index 6caf49e1..b7cc0425 100644
--- a/examples/datavisualization/graphgallery/surfacegraph.cpp
+++ b/examples/datavisualization/graphgallery/surfacegraph.cpp
@@ -19,13 +19,9 @@ using namespace Qt::StringLiterals;
 SurfaceGraph::SurfaceGraph()
 {
     m_surfaceGraph = new Q3DSurface();
-    m_container = QWidget::createWindowContainer(m_surfaceGraph);
 }
 
-SurfaceGraph::~SurfaceGraph()
-{
-    delete m_container;
-}
+SurfaceGraph::~SurfaceGraph() = default;
 
 bool SurfaceGraph::initialize()
 {
@@ -36,16 +32,17 @@ bool SurfaceGraph::initialize()
         return -1;
     }
 
+    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->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
     m_container->setFocusPolicy(Qt::StrongFocus);
+    hLayout->addWidget(m_container, 1);
 
-    m_surfaceWidget = new QWidget;
-    QHBoxLayout *hLayout = new QHBoxLayout(m_surfaceWidget);
     QVBoxLayout *vLayout = new QVBoxLayout();
-    hLayout->addWidget(m_container, 1);
     hLayout->addLayout(vLayout);
     vLayout->setAlignment(Qt::AlignTop);