diff options
author | Friedemann Kleint <Friedemann.Kleint@qt.io> | 2023-11-15 21:57:42 +0100 |
---|---|---|
committer | Friedemann Kleint <Friedemann.Kleint@qt.io> | 2023-12-06 18:22:41 +0100 |
commit | a3e20df03d522bd1b07ac7a85578401f36f290b9 (patch) | |
tree | f4ed5be0841a6b38e16fd1fb4bf6ddee46eadc0a /examples | |
parent | 283cdcd3d5fad368c9df1bcae69cbfbf9ade623f (diff) |
Polish the SimpleTreeModel example
- Fix/silence most clang-tidy/compiler warnings
* unsigned/int comparison
* Avoid repeating return / default parameter types
* Make functions static/use static invocations
* Use string literals everywhere
* Use auto * for pointers
* Streamline code, use ternary operators
* Move constructor parameters
* Observe rule of 5 by using Q_DISABLE_COPY_MOVE
- Add some bells && whistles, resize properly, expand all
Complements 25027444a9b53d61a6257dc5f5ce0ffdb3b06f98.
Pick-to: 6.6
Change-Id: I78f48d187981ecabf69a5d4d42715bad026fa9e6
Reviewed-by: Kai Köhne <kai.koehne@qt.io>
Diffstat (limited to 'examples')
6 files changed, 52 insertions, 61 deletions
diff --git a/examples/widgets/doc/src/simpletreemodel.qdoc b/examples/widgets/doc/src/simpletreemodel.qdoc index 55b4f139f0..10e79e2845 100644 --- a/examples/widgets/doc/src/simpletreemodel.qdoc +++ b/examples/widgets/doc/src/simpletreemodel.qdoc @@ -145,8 +145,9 @@ \snippet itemviews/simpletreemodel/treeitem.cpp 4 - Column data is returned by the \c data() function. The bounds are checked - before accessing the container with the data: + Column data is returned by the \c data() function. We use + the QList::value() convenience function which checks the bounds + and returns a default-constructed QVariant in case they are violated: \snippet itemviews/simpletreemodel/treeitem.cpp 5 diff --git a/examples/widgets/itemviews/simpletreemodel/main.cpp b/examples/widgets/itemviews/simpletreemodel/main.cpp index ee8edb7c13..5800c595c8 100644 --- a/examples/widgets/itemviews/simpletreemodel/main.cpp +++ b/examples/widgets/itemviews/simpletreemodel/main.cpp @@ -5,20 +5,28 @@ #include <QApplication> #include <QFile> +#include <QScreen> #include <QTreeView> +using namespace Qt::StringLiterals; + int main(int argc, char *argv[]) { QApplication app(argc, argv); - QFile file(":/default.txt"); - file.open(QIODevice::ReadOnly); - TreeModel model(file.readAll()); + QFile file(":/default.txt"_L1); + file.open(QIODevice::ReadOnly | QIODevice::Text); + TreeModel model(QString::fromUtf8(file.readAll())); file.close(); QTreeView view; view.setModel(&model); - view.setWindowTitle(QObject::tr("Simple Tree Model")); + view.setWindowTitle(TreeModel::tr("Simple Tree Model")); + for (int c = 0; c < model.columnCount(); ++c) + view.resizeColumnToContents(c); + view.expandAll(); + const auto screenSize = view.screen()->availableSize(); + view.resize({screenSize.width() / 2, screenSize.height() * 2 / 3}); view.show(); - return app.exec(); + return QCoreApplication::exec(); } diff --git a/examples/widgets/itemviews/simpletreemodel/treeitem.cpp b/examples/widgets/itemviews/simpletreemodel/treeitem.cpp index 611a6a0976..67e021d622 100644 --- a/examples/widgets/itemviews/simpletreemodel/treeitem.cpp +++ b/examples/widgets/itemviews/simpletreemodel/treeitem.cpp @@ -10,8 +10,8 @@ #include "treeitem.h" //! [0] -TreeItem::TreeItem(const QVariantList &data, TreeItem *parent) - : m_itemData(data), m_parentItem(parent) +TreeItem::TreeItem(QVariantList data, TreeItem *parent) + : m_itemData(std::move(data)), m_parentItem(parent) {} //! [0] @@ -25,32 +25,28 @@ void TreeItem::appendChild(std::unique_ptr<TreeItem> &&child) //! [2] TreeItem *TreeItem::child(int row) { - if (row < 0 || row >= m_childItems.size()) - return nullptr; - return m_childItems.at(row).get(); + return row >= 0 && row < childCount() ? m_childItems.at(row).get() : nullptr; } //! [2] //! [3] int TreeItem::childCount() const { - return m_childItems.size(); + return int(m_childItems.size()); } //! [3] //! [4] int TreeItem::columnCount() const { - return m_itemData.count(); + return int(m_itemData.count()); } //! [4] //! [5] QVariant TreeItem::data(int column) const { - if (column < 0 || column >= m_itemData.size()) - return QVariant(); - return m_itemData.at(column); + return m_itemData.value(column); } //! [5] @@ -64,11 +60,11 @@ TreeItem *TreeItem::parentItem() //! [7] int TreeItem::row() const { - if (!m_parentItem) + if (m_parentItem == nullptr) 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); + return treeItem.get() == this; }); if (it != m_parentItem->m_childItems.cend()) diff --git a/examples/widgets/itemviews/simpletreemodel/treeitem.h b/examples/widgets/itemviews/simpletreemodel/treeitem.h index 8edebcc34b..b9002f06fd 100644 --- a/examples/widgets/itemviews/simpletreemodel/treeitem.h +++ b/examples/widgets/itemviews/simpletreemodel/treeitem.h @@ -11,7 +11,7 @@ class TreeItem { public: - explicit TreeItem(const QVariantList &data, TreeItem *parentItem = nullptr); + explicit TreeItem(QVariantList data, TreeItem *parentItem = nullptr); void appendChild(std::unique_ptr<TreeItem> &&child); diff --git a/examples/widgets/itemviews/simpletreemodel/treemodel.cpp b/examples/widgets/itemviews/simpletreemodel/treemodel.cpp index 93cd6709a9..8f2e52f657 100644 --- a/examples/widgets/itemviews/simpletreemodel/treemodel.cpp +++ b/examples/widgets/itemviews/simpletreemodel/treemodel.cpp @@ -40,14 +40,10 @@ int TreeModel::columnCount(const QModelIndex &parent) const //! [3] QVariant TreeModel::data(const QModelIndex &index, int role) const { - if (!index.isValid()) - return QVariant(); - - if (role != Qt::DisplayRole) - return QVariant(); - - auto item = static_cast<TreeItem*>(index.internalPointer()); + if (!index.isValid() || role != Qt::DisplayRole) + return {}; + const auto *item = static_cast<const TreeItem*>(index.internalPointer()); return item->data(index.column()); } //! [3] @@ -55,10 +51,8 @@ QVariant TreeModel::data(const QModelIndex &index, int role) const //! [4] Qt::ItemFlags TreeModel::flags(const QModelIndex &index) const { - if (!index.isValid()) - return Qt::NoItemFlags; - - return QAbstractItemModel::flags(index); + return index.isValid() + ? QAbstractItemModel::flags(index) : Qt::ItemFlags(Qt::NoItemFlags); } //! [4] @@ -66,10 +60,8 @@ Qt::ItemFlags TreeModel::flags(const QModelIndex &index) const QVariant TreeModel::headerData(int section, Qt::Orientation orientation, int role) const { - if (orientation == Qt::Horizontal && role == Qt::DisplayRole) - return rootItem->data(section); - - return QVariant(); + return orientation == Qt::Horizontal && role == Qt::DisplayRole + ? rootItem->data(section) : QVariant{}; } //! [5] @@ -77,19 +69,15 @@ QVariant TreeModel::headerData(int section, Qt::Orientation orientation, QModelIndex TreeModel::index(int row, int column, const QModelIndex &parent) const { if (!hasIndex(row, column, parent)) - return QModelIndex(); + return {}; - TreeItem *parentItem; + TreeItem *parentItem = parent.isValid() + ? static_cast<TreeItem*>(parent.internalPointer()) + : rootItem.get(); - if (!parent.isValid()) - parentItem = rootItem.get(); - else - parentItem = static_cast<TreeItem*>(parent.internalPointer()); - - auto childItem = parentItem->child(row); - if (childItem) + if (auto *childItem = parentItem->child(row)) return createIndex(row, column, childItem); - return QModelIndex(); + return {}; } //! [6] @@ -97,29 +85,25 @@ QModelIndex TreeModel::index(int row, int column, const QModelIndex &parent) con QModelIndex TreeModel::parent(const QModelIndex &index) const { if (!index.isValid()) - return QModelIndex(); + return {}; - TreeItem *childItem = static_cast<TreeItem*>(index.internalPointer()); + auto *childItem = static_cast<TreeItem*>(index.internalPointer()); TreeItem *parentItem = childItem->parentItem(); - if (parentItem == rootItem.get()) - return QModelIndex(); - - return createIndex(parentItem->row(), 0, parentItem); + return parentItem != rootItem.get() + ? createIndex(parentItem->row(), 0, parentItem) : QModelIndex{}; } //! [7] //! [8] int TreeModel::rowCount(const QModelIndex &parent) const { - TreeItem *parentItem; if (parent.column() > 0) return 0; - if (!parent.isValid()) - parentItem = rootItem.get(); - else - parentItem = static_cast<TreeItem*>(parent.internalPointer()); + const TreeItem *parentItem = parent.isValid() + ? static_cast<const TreeItem*>(parent.internalPointer()) + : rootItem.get(); return parentItem->childCount(); } diff --git a/examples/widgets/itemviews/simpletreemodel/treemodel.h b/examples/widgets/itemviews/simpletreemodel/treemodel.h index 0a771088ed..55c72bb3bd 100644 --- a/examples/widgets/itemviews/simpletreemodel/treemodel.h +++ b/examples/widgets/itemviews/simpletreemodel/treemodel.h @@ -16,21 +16,23 @@ class TreeModel : public QAbstractItemModel Q_OBJECT public: + Q_DISABLE_COPY_MOVE(TreeModel) + explicit TreeModel(const QString &data, QObject *parent = nullptr); - ~TreeModel(); + ~TreeModel() override; QVariant data(const QModelIndex &index, int role) const override; Qt::ItemFlags flags(const QModelIndex &index) const override; QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const override; QModelIndex index(int row, int column, - const QModelIndex &parent = QModelIndex()) const override; + const QModelIndex &parent = {}) const override; QModelIndex parent(const QModelIndex &index) const override; - int rowCount(const QModelIndex &parent = QModelIndex()) const override; - int columnCount(const QModelIndex &parent = QModelIndex()) const override; + int rowCount(const QModelIndex &parent = {}) const override; + int columnCount(const QModelIndex &parent = {}) const override; private: - void setupModelData(const QStringList &lines, TreeItem *parent); + static void setupModelData(const QStringList &lines, TreeItem *parent); std::unique_ptr<TreeItem> rootItem; }; |