Modernize EditableTreeModel

- Use unique_ptr instead of manual memory management
- Improve consistenty in variable name with the simpletreemodel
  childrenNumber -> row, m_ prefix for member variables

Change-Id: Iface30c2224c2b1db7c623a9e6fcbb449c556f3e
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

4 files changed, 63 insertions, 64 deletions

diff --git a/examples/widgets/itemviews/editabletreemodel/treeitem.cpp b/examples/widgets/itemviews/editabletreemodel/treeitem.cpp
index 942ba277a3..dbdaaeb5d2 100644
--- a/examples/widgets/itemviews/editabletreemodel/treeitem.cpp
+++ b/examples/widgets/itemviews/editabletreemodel/treeitem.cpp
@@ -10,76 +10,77 @@
 #include "treeitem.h"
 
 //! [0]
-TreeItem::TreeItem(const QList<QVariant> &data, TreeItem *parent)
-    : itemData(data), parentItem(parent)
+TreeItem::TreeItem(const QVariantList &data, TreeItem *parent)
+    : itemData(data), m_parentItem(parent)
 {}
 //! [0]
 
 //! [1]
-TreeItem::~TreeItem()
+TreeItem *TreeItem::child(int number)
 {
-    qDeleteAll(childItems);
+    if (number < 0 || number >= m_childItems.size())
+        return nullptr;
+    return m_childItems.at(number).get();
 }
 //! [1]
 
 //! [2]
-TreeItem *TreeItem::child(int number)
+int TreeItem::childCount() const
 {
-    if (number < 0 || number >= childItems.size())
-        return nullptr;
-    return childItems.at(number);
+    return m_childItems.size();
 }
 //! [2]
 
 //! [3]
-int TreeItem::childCount() const
+int TreeItem::row() const
 {
-    return childItems.count();
+    if (!m_parentItem)
+        return 0;
+    const auto it = std::find_if(m_parentItem->m_childItems.cbegin(), m_parentItem->m_childItems.cend(),
+                                 [this](const std::unique_ptr<TreeItem> &treeItem) {
+        return treeItem.get() == const_cast<TreeItem *>(this);
+    });
+
+    if (it != m_parentItem->m_childItems.cend())
+        return std::distance(m_parentItem->m_childItems.cbegin(), it);
+    Q_ASSERT(false); // should not happen
+    return -1;
 }
 //! [3]
 
 //! [4]
-int TreeItem::childNumber() const
-{
-    if (parentItem)
-        return parentItem->childItems.indexOf(const_cast<TreeItem*>(this));
-    return 0;
-}
-//! [4]
-
-//! [5]
 int TreeItem::columnCount() const
 {
     return itemData.count();
 }
-//! [5]
+//! [4]
 
-//! [6]
+//! [5]
 QVariant TreeItem::data(int column) const
 {
     if (column < 0 || column >= itemData.size())
         return QVariant();
     return itemData.at(column);
 }
-//! [6]
+//! [5]
 
-//! [7]
+//! [6]
 bool TreeItem::insertChildren(int position, int count, int columns)
 {
-    if (position < 0 || position > childItems.size())
+    if (position < 0 || position > m_childItems.size())
         return false;
 
     for (int row = 0; row < count; ++row) {
-        QList<QVariant> data(columns);
-        TreeItem *item = new TreeItem(data, this);
-        childItems.insert(position, item);
+        QVariantList data(columns);
+        m_childItems.insert(m_childItems.cbegin() + position,
+                std::make_unique<TreeItem>(data, this));
     }
 
     return true;
 }
-//! [7]
+//! [6]
 
-//! [8]
+//! [7]
 bool TreeItem::insertColumns(int position, int columns)
 {
     if (position < 0 || position > itemData.size())
@@ -88,32 +89,32 @@ bool TreeItem::insertColumns(int position, int columns)
     for (int column = 0; column < columns; ++column)
         itemData.insert(position, QVariant());
 
-    for (TreeItem *child : std::as_const(childItems))
+    for (auto &child : std::as_const(m_childItems))
         child->insertColumns(position, columns);
 
     return true;
 }
-//! [8]
+//! [7]
 
-//! [9]
+//! [8]
 TreeItem *TreeItem::parent()
 {
-    return parentItem;
+    return m_parentItem;
 }
-//! [9]
+//! [8]
 
-//! [10]
+//! [9]
 bool TreeItem::removeChildren(int position, int count)
 {
-    if (position < 0 || position + count > childItems.size())
+    if (position < 0 || position + count > m_childItems.size())
         return false;
 
     for (int row = 0; row < count; ++row)
-        delete childItems.takeAt(position);
+        m_childItems.erase(m_childItems.cbegin() + position);
 
     return true;
 }
-//! [10]
+//! [9]
 
 bool TreeItem::removeColumns(int position, int columns)
 {
@@ -123,13 +124,13 @@ bool TreeItem::removeColumns(int position, int columns)
     for (int column = 0; column < columns; ++column)
         itemData.remove(position);
 
-    for (TreeItem *child : std::as_const(childItems))
+    for (auto &child : std::as_const(m_childItems))
         child->removeColumns(position, columns);
 
     return true;
 }
 
-//! [11]
+//! [10]
 bool TreeItem::setData(int column, const QVariant &value)
 {
     if (column < 0 || column >= itemData.size())
@@ -138,4 +139,4 @@ bool TreeItem::setData(int column, const QVariant &value)
     itemData[column] = value;
     return true;
 }
-//! [11]
+//! [10]
diff --git a/examples/widgets/itemviews/editabletreemodel/treeitem.h b/examples/widgets/itemviews/editabletreemodel/treeitem.h
index cbc818c081..d30047dd2a 100644
--- a/examples/widgets/itemviews/editabletreemodel/treeitem.h
+++ b/examples/widgets/itemviews/editabletreemodel/treeitem.h
@@ -11,8 +11,7 @@
 class TreeItem
 {
 public:
-    explicit TreeItem(const QList<QVariant> &data, TreeItem *parent = nullptr);
-    ~TreeItem();
+    explicit TreeItem(const QVariantList &data, TreeItem *parent = nullptr);
 
     TreeItem *child(int number);
     int childCount() const;
@@ -23,13 +22,13 @@ public:
     TreeItem *parent();
     bool removeChildren(int position, int count);
     bool removeColumns(int position, int columns);
-    int childNumber() const;
+    int row() const;
     bool setData(int column, const QVariant &value);
 
 private:
-    QList<TreeItem *> childItems;
-    QList<QVariant> itemData;
-    TreeItem *parentItem;
+    std::vector<std::unique_ptr<TreeItem>> m_childItems;
+    QVariantList itemData;
+    TreeItem *m_parentItem;
 };
 //! [0]
 
diff --git a/examples/widgets/itemviews/editabletreemodel/treemodel.cpp b/examples/widgets/itemviews/editabletreemodel/treemodel.cpp
index 290ec186a8..e02a82ec46 100644
--- a/examples/widgets/itemviews/editabletreemodel/treemodel.cpp
+++ b/examples/widgets/itemviews/editabletreemodel/treemodel.cpp
@@ -6,24 +6,23 @@
 
 #include <QtWidgets>
 
+using namespace Qt::StringLiterals;
+
 //! [0]
 TreeModel::TreeModel(const QStringList &headers, const QString &data, QObject *parent)
     : QAbstractItemModel(parent)
 {
-    QList<QVariant> rootData;
+    QVariantList rootData;
     for (const QString &header : headers)
         rootData << header;
 
-    rootItem = new TreeItem(rootData);
-    setupModelData(data.split('\n'), rootItem);
+    rootItem = std::make_unique<TreeItem>(rootData);
+    setupModelData(data.split('\n'_L1));
 }
 //! [0]
 
 //! [1]
-TreeModel::~TreeModel()
-{
-    delete rootItem;
-}
+TreeModel::~TreeModel() = default;
 //! [1]
 
 //! [2]
@@ -65,7 +64,7 @@ TreeItem *TreeModel::getItem(const QModelIndex &index) const
         if (item)
             return item;
     }
-    return rootItem;
+    return rootItem.get();
 }
 //! [4]
 
@@ -130,10 +129,10 @@ QModelIndex TreeModel::parent(const QModelIndex &index) const
     TreeItem *childItem = getItem(index);
     TreeItem *parentItem = childItem ? childItem->parent() : nullptr;
 
-    if (parentItem == rootItem || !parentItem)
+    if (parentItem == rootItem.get() || !parentItem)
         return QModelIndex();
 
-    return createIndex(parentItem->childNumber(), 0, parentItem);
+    return createIndex(parentItem->row(), 0, parentItem);
 }
 //! [7]
 
@@ -202,11 +201,11 @@ bool TreeModel::setHeaderData(int section, Qt::Orientation orientation,
     return result;
 }
 
-void TreeModel::setupModelData(const QStringList &lines, TreeItem *parent)
+void TreeModel::setupModelData(const QStringList &lines)
 {
     QList<TreeItem *> parents;
     QList<int> indentations;
-    parents << parent;
+    parents << rootItem.get();
     indentations << 0;
 
     int number = 0;
@@ -214,7 +213,7 @@ void TreeModel::setupModelData(const QStringList &lines, TreeItem *parent)
     while (number < lines.count()) {
         int position = 0;
         while (position < lines[number].length()) {
-            if (lines[number].at(position) != ' ')
+            if (lines[number].at(position) != ' '_L1)
                 break;
             ++position;
         }
@@ -224,8 +223,8 @@ void TreeModel::setupModelData(const QStringList &lines, TreeItem *parent)
         if (!lineData.isEmpty()) {
             // Read the column data from the rest of the line.
             const QStringList columnStrings =
-                lineData.split(QLatin1Char('\t'), Qt::SkipEmptyParts);
-            QList<QVariant> columnData;
+                lineData.split('\t'_L1, Qt::SkipEmptyParts);
+            QVariantList columnData;
             columnData.reserve(columnStrings.size());
             for (const QString &columnString : columnStrings)
                 columnData << columnString;
diff --git a/examples/widgets/itemviews/editabletreemodel/treemodel.h b/examples/widgets/itemviews/editabletreemodel/treemodel.h
index 1482846c29..6fbd296de2 100644
--- a/examples/widgets/itemviews/editabletreemodel/treemodel.h
+++ b/examples/widgets/itemviews/editabletreemodel/treemodel.h
@@ -50,10 +50,10 @@ public:
                     const QModelIndex &parent = QModelIndex()) override;
 
 private:
-    void setupModelData(const QStringList &lines, TreeItem *parent);
+    void setupModelData(const QStringList &lines);
     TreeItem *getItem(const QModelIndex &index) const;
 
-    TreeItem *rootItem;
+    std::unique_ptr<TreeItem> rootItem;
 };
 //! [2]