diff options
| author | Volker Hilsheimer <volker.hilsheimer@qt.io> | 2025-12-04 20:19:57 +0100 |
|---|---|---|
| committer | Volker Hilsheimer <volker.hilsheimer@qt.io> | 2025-12-05 18:10:05 +0100 |
| commit | 93fb8b0db67639495e345c70aa80a74fd579180a (patch) | |
| tree | 967e1d0f4baebbac7127bef1b03e15f9794305e9 | |
| parent | 9f9d282af984baa5e2bf0b699a7c8e3d4a8a6fbe (diff) | |
QRM: implement itemData in terms of multiData
No need to duplicate the entire logic. The only overhead is that we have
to create a QModelRoleDataSpan for all roles, except our internal roles.
Using a QVarLengthArray makes that cheap.
The only special case we keep is for items that are backed by a type
that is directly convertible to a QMap<int, QVariant>. This comes with
a small overhead for acessing the element at runtime.
Pick-to: 6.10
Change-Id: I33f86d231bef9036a7e83584d1bf013f129b8075
Reviewed-by: Artem Dyomin <artem.dyomin@qt.io>
| -rw-r--r-- | src/corelib/itemmodels/qrangemodel_impl.h | 84 |
1 files changed, 23 insertions, 61 deletions
diff --git a/src/corelib/itemmodels/qrangemodel_impl.h b/src/corelib/itemmodels/qrangemodel_impl.h index 544e66d2211..0233727f848 100644 --- a/src/corelib/itemmodels/qrangemodel_impl.h +++ b/src/corelib/itemmodels/qrangemodel_impl.h @@ -23,6 +23,7 @@ #include <QtCore/qmap.h> #include <QtCore/qscopedvaluerollback.h> #include <QtCore/qset.h> +#include <QtCore/qvarlengtharray.h> #include <algorithm> #include <functional> @@ -1217,73 +1218,34 @@ public: QMap<int, QVariant> itemData(const QModelIndex &index) const { QMap<int, QVariant> result; - bool tried = false; - const auto readItemData = [this, &index, &result, &tried](const auto &value){ - Q_UNUSED(this); - Q_UNUSED(index); - using value_type = q20::remove_cvref_t<decltype(value)>; - using multi_role = QRangeModelDetails::is_multi_role<value_type>; - using wrapped_value_type = QRangeModelDetails::wrapped_t<value_type>; - if constexpr (QRangeModelDetails::item_access<wrapped_value_type>()) { - using ItemAccess = QRangeModelDetails::QRangeModelItemAccess<wrapped_value_type>; - tried = true; + if (index.isValid()) { + bool tried = false; + + // optimisation for items backed by a QMap<int, QVariant> or equivalent + readAt(index, [&result, &tried](const auto &value) { + if constexpr (std::is_convertible_v<decltype(value), decltype(result)>) { + tried = true; + result = value; + } + }); + if (!tried) { const auto roles = this->itemModel().roleNames().keys(); - for (auto &role : roles) { + QVarLengthArray<QModelRoleData, 16> roleDataArray; + roleDataArray.reserve(roles.size()); + for (auto role : roles) { if (isRangeModelRole(role)) continue; - QVariant data = ItemAccess::readRole(value, role); - if (data.isValid()) - result[role] = std::move(data); + roleDataArray.emplace_back(role); } - } else if constexpr (multi_role()) { - tried = true; - if constexpr (std::is_convertible_v<value_type, decltype(result)>) { - result = value; - } else { - const auto roleNames = [this]() -> QHash<int, QByteArray> { - Q_UNUSED(this); - if constexpr (!multi_role::int_key) - return this->itemModel().roleNames(); - else - return {}; - }(); - for (auto it = std::begin(value); it != std::end(value); ++it) { - const int role = [&roleNames, key = QRangeModelDetails::key(it)]() { - Q_UNUSED(roleNames); - if constexpr (multi_role::int_key) - return int(key); - else - return roleNames.key(key.toUtf8(), -1); - }(); - - if (role != -1 && role != Qt::RangeModelDataRole && role != Qt::RangeModelAdapterRole) - result.insert(role, QRangeModelDetails::value(it)); - } - } - } else if constexpr (has_metaobject<value_type>) { - if (row_traits::fixed_size() <= 1) { - tried = true; - const auto roleNames = this->itemModel().roleNames(); - const auto end = roleNames.keyEnd(); - for (auto it = roleNames.keyBegin(); it != end; ++it) { - const int role = *it; - if (isRangeModelRole(role)) - continue; - QVariant data = readRole(index, role, QRangeModelDetails::pointerTo(value)); - if (data.isValid()) - result[role] = std::move(data); - } - } - } - }; - - if (index.isValid()) { - readAt(index, readItemData); + QModelRoleDataSpan roleDataSpan(roleDataArray); + multiData(index, roleDataSpan); - if (!tried) { // no multi-role item found - result = this->itemModel().QAbstractItemModel::itemData(index); - result.remove(Qt::RangeModelAdapterRole); + for (auto &&roleData : std::move(roleDataSpan)) { + QVariant data = roleData.data(); + if (data.isValid()) + result[roleData.role()] = std::move(data); + } } } return result; |