Turn SpinBox Delegate example into snippets

The essence of the example was already fully quoted in the
model/view documentation. Move the code into a snippet
source, and update the screenshot.

Fixes: QTBUG-119976
Pick-to: 6.7 6.6
Change-Id: Id2f10bb26a650419969bbfa9b76cb74babd3319e
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>
Reviewed-by: Andreas Eliasson <andreas.eliasson@qt.io>

2 files changed, 91 insertions, 0 deletions

diff --git a/src/widgets/doc/snippets/qitemdelegate/CMakeLists.txt b/src/widgets/doc/snippets/qitemdelegate/CMakeLists.txt
new file mode 100644
index 0000000000..43f30c8aa5
--- /dev/null
+++ b/src/widgets/doc/snippets/qitemdelegate/CMakeLists.txt
@@ -0,0 +1,12 @@
+# Copyright (C) 2023 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+add_library(widgets_qitemdelegate_snippets OBJECT
+    spinbox-delegate.cpp
+)
+
+target_link_libraries(widgets_qitemdelegate_snippets PRIVATE
+    Qt::Core
+    Qt::Gui
+    Qt::Widgets
+)
diff --git a/src/widgets/doc/snippets/qitemdelegate/spinbox-delegate.cpp b/src/widgets/doc/snippets/qitemdelegate/spinbox-delegate.cpp
new file mode 100644
index 0000000000..efe8a16733
--- /dev/null
+++ b/src/widgets/doc/snippets/qitemdelegate/spinbox-delegate.cpp
@@ -0,0 +1,79 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#include <QStyledItemDelegate>
+#include <QSpinBox>
+
+//! [declaration]
+class SpinBoxDelegate : public QStyledItemDelegate
+{
+    Q_OBJECT
+
+public:
+    SpinBoxDelegate(QObject *parent = nullptr);
+
+    QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &option,
+                          const QModelIndex &index) const override;
+
+    void setEditorData(QWidget *editor, const QModelIndex &index) const override;
+    void setModelData(QWidget *editor, QAbstractItemModel *model,
+                      const QModelIndex &index) const override;
+
+    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option,
+                              const QModelIndex &index) const override;
+};
+//! [declaration]
+
+//! [constructor]
+SpinBoxDelegate::SpinBoxDelegate(QObject *parent)
+    : QStyledItemDelegate(parent)
+{
+}
+//! [constructor]
+
+//! [createEditor]
+QWidget *SpinBoxDelegate::createEditor(QWidget *parent,
+                                       const QStyleOptionViewItem &/* option */,
+                                       const QModelIndex &/* index */) const
+{
+    QSpinBox *editor = new QSpinBox(parent);
+    editor->setFrame(false);
+    editor->setMinimum(0);
+    editor->setMaximum(100);
+
+    return editor;
+}
+//! [createEditor]
+
+//! [setEditorData]
+void SpinBoxDelegate::setEditorData(QWidget *editor,
+                                    const QModelIndex &index) const
+{
+    int value = index.model()->data(index, Qt::EditRole).toInt();
+
+    QSpinBox *spinBox = static_cast<QSpinBox*>(editor);
+    spinBox->setValue(value);
+}
+//! [setEditorData]
+
+//! [setModelData]
+void SpinBoxDelegate::setModelData(QWidget *editor, QAbstractItemModel *model,
+                                   const QModelIndex &index) const
+{
+    QSpinBox *spinBox = static_cast<QSpinBox*>(editor);
+    spinBox->interpretText();
+    int value = spinBox->value();
+
+    model->setData(index, value, Qt::EditRole);
+}
+//! [setModelData]
+
+//! [updateEditorGeometry]
+void SpinBoxDelegate::updateEditorGeometry(QWidget *editor,
+                                           const QStyleOptionViewItem &option,
+                                           const QModelIndex &/* index */) const
+{
+    editor->setGeometry(option.rect);
+}
+//! [updateEditorGeometry]
+