qqmlobjectmodel.cpp

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qqmlobjectmodel_p.h"
 
#include <QtCore/qcoreapplication.h>
#include <QtQml/qqmlcontext.h>
#include <QtQml/qqmlengine.h>
#include <QtQml/qqmlinfo.h>
 
#include <private/qqmlchangeset_p.h>
#include <private/qqmlglobal_p.h>
#include <private/qobject_p.h>
#include <private/qpodvector_p.h>
 
#include <QtCore/qhash.h>
#include <QtCore/qlist.h>
 
QT_BEGIN_NAMESPACE
 
QHash<QObject*, QQmlObjectModelAttached*> QQmlObjectModelAttached::attachedProperties;
 
 
class QQmlObjectModelPrivate : public QObjectPrivate
{
    Q_DECLARE_PUBLIC(QQmlObjectModel)
public:
    class Item {
    public:
        Item(QObject *i) : item(i), ref(0) {}
 
        void addRef() { ++ref; }
        bool deref() { return --ref == 0; }
 
        QObject *item;
        int ref;
    };
 
    QQmlObjectModelPrivate() : QObjectPrivate(), moveId(0) {}
 
    static void children_append(QQmlListProperty<QObject> *prop, QObject *item) {
        qsizetype index = static_cast<QQmlObjectModelPrivate *>(prop->data)->children.size();
        static_cast<QQmlObjectModelPrivate *>(prop->data)->insert(index, item);
    }
 
    static qsizetype children_count(QQmlListProperty<QObject> *prop) {
        return static_cast<QQmlObjectModelPrivate *>(prop->data)->children.size();
    }
 
    static QObject *children_at(QQmlListProperty<QObject> *prop, qsizetype index) {
        return static_cast<QQmlObjectModelPrivate *>(prop->data)->children.at(index).item;
    }
 
    static void children_clear(QQmlListProperty<QObject> *prop) {
        static_cast<QQmlObjectModelPrivate *>(prop->data)->clear();
    }
 
    static void children_replace(QQmlListProperty<QObject> *prop, qsizetype index, QObject *item) {
        static_cast<QQmlObjectModelPrivate *>(prop->data)->replace(index, item);
    }
 
    static void children_removeLast(QQmlListProperty<QObject> *prop) {
        auto data = static_cast<QQmlObjectModelPrivate *>(prop->data);
        data->remove(data->children.size() - 1, 1);
    }
 
    void insert(int index, QObject *item) {
        Q_Q(QQmlObjectModel);
        children.insert(index, Item(item));
        for (int i = index; i < children.size(); ++i) {
            QQmlObjectModelAttached *attached = QQmlObjectModelAttached::properties(children.at(i).item);
            attached->setIndex(i);
        }
        QQmlChangeSet changeSet;
        changeSet.insert(index, 1);
        emit q->modelUpdated(changeSet, false);
        emit q->countChanged();
        emit q->childrenChanged();
    }
 
    void replace(int index, QObject *item) {
        Q_Q(QQmlObjectModel);
        auto *attached = QQmlObjectModelAttached::properties(children.at(index).item);
        attached->setIndex(-1);
        children.replace(index, Item(item));
        QQmlObjectModelAttached::properties(children.at(index).item)->setIndex(index);
        QQmlChangeSet changeSet;
        changeSet.change(index, 1);
        emit q->modelUpdated(changeSet, false);
        emit q->childrenChanged();
    }
 
    void move(int from, int to, int n) {
        Q_Q(QQmlObjectModel);
        if (from > to) {
            // Only move forwards - flip if backwards moving
            int tfrom = from;
            int tto = to;
            from = tto;
            to = tto+n;
            n = tfrom-tto;
        }
 
        QPODVector<QQmlObjectModelPrivate::Item, 4> store;
        for (int i = 0; i < to - from; ++i)
            store.append(children[from + n + i]);
        for (int i = 0; i < n; ++i)
            store.append(children[from + i]);
 
        for (int i = 0; i < store.count(); ++i) {
            children[from + i] = store[i];
            QQmlObjectModelAttached *attached = QQmlObjectModelAttached::properties(children.at(from + i).item);
            attached->setIndex(from + i);
        }
 
        QQmlChangeSet changeSet;
        changeSet.move(from, to, n, ++moveId);
        emit q->modelUpdated(changeSet, false);
        emit q->childrenChanged();
    }
 
    void remove(int index, int n) {
        Q_Q(QQmlObjectModel);
        for (int i = index; i < index + n; ++i) {
            QQmlObjectModelAttached *attached = QQmlObjectModelAttached::properties(children.at(i).item);
            attached->setIndex(-1);
        }
        children.erase(children.begin() + index, children.begin() + index + n);
        for (int i = index; i < children.size(); ++i) {
            QQmlObjectModelAttached *attached = QQmlObjectModelAttached::properties(children.at(i).item);
            attached->setIndex(i);
        }
        QQmlChangeSet changeSet;
        changeSet.remove(index, n);
        emit q->modelUpdated(changeSet, false);
        emit q->countChanged();
        emit q->childrenChanged();
    }
 
    void clear() {
        Q_Q(QQmlObjectModel);
        const auto copy = children;
        for (const Item &child : copy)
            emit q->destroyingItem(child.item);
        remove(0, children.size());
    }
 
    int indexOf(QObject *item) const {
        for (int i = 0; i < children.size(); ++i)
            if (children.at(i).item == item)
                return i;
        return -1;
    }
 
    uint moveId;
    QList<Item> children;
};
 
Q_DECLARE_TYPEINFO(QQmlObjectModelPrivate::Item, Q_PRIMITIVE_TYPE);
 
 
QQmlObjectModel::QQmlObjectModel(QObject *parent)
    : QQmlInstanceModel(*(new QQmlObjectModelPrivate), parent)
{
}
 
QQmlListProperty<QObject> QQmlObjectModel::children()
{
    Q_D(QQmlObjectModel);
    return QQmlListProperty<QObject>(this, d,
                                     QQmlObjectModelPrivate::children_append,
                                     QQmlObjectModelPrivate::children_count,
                                     QQmlObjectModelPrivate::children_at,
                                     QQmlObjectModelPrivate::children_clear,
                                     QQmlObjectModelPrivate::children_replace,
                                     QQmlObjectModelPrivate::children_removeLast);
}
 
int QQmlObjectModel::count() const
{
    Q_D(const QQmlObjectModel);
    return d->children.size();
}
 
bool QQmlObjectModel::isValid() const
{
    return true;
}
 
QObject *QQmlObjectModel::object(int index, QQmlIncubator::IncubationMode)
{
    Q_D(QQmlObjectModel);
    QQmlObjectModelPrivate::Item &item = d->children[index];
    item.addRef();
    if (item.ref == 1) {
        emit initItem(index, item.item);
        emit createdItem(index, item.item);
    }
    return item.item;
}
 
QQmlInstanceModel::ReleaseFlags QQmlObjectModel::release(QObject *item, ReusableFlag)
{
    Q_D(QQmlObjectModel);
    int idx = d->indexOf(item);
    if (idx >= 0) {
        if (!d->children[idx].deref())
            return QQmlInstanceModel::Referenced;
    }
    return {};
}
 
QVariant QQmlObjectModel::variantValue(int index, const QString &role)
{
    Q_D(QQmlObjectModel);
    if (index < 0 || index >= d->children.size())
        return QString();
    return d->children.at(index).item->property(role.toUtf8().constData());
}
 
QQmlIncubator::Status QQmlObjectModel::incubationStatus(int)
{
    return QQmlIncubator::Ready;
}
 
int QQmlObjectModel::indexOf(QObject *item, QObject *) const
{
    Q_D(const QQmlObjectModel);
    return d->indexOf(item);
}
 
QQmlObjectModelAttached *QQmlObjectModel::qmlAttachedProperties(QObject *obj)
{
    return QQmlObjectModelAttached::properties(obj);
}
 
QObject *QQmlObjectModel::get(int index) const
{
    Q_D(const QQmlObjectModel);
    if (index < 0 || index >= d->children.size())
        return nullptr;
    return d->children.at(index).item;
}
 
void QQmlObjectModel::append(QObject *object)
{
    Q_D(QQmlObjectModel);
    d->insert(count(), object);
}
 
void QQmlObjectModel::insert(int index, QObject *object)
{
    Q_D(QQmlObjectModel);
    if (index < 0 || index > count()) {
        qmlWarning(this) << tr("insert: index %1 out of range").arg(index);
        return;
    }
    d->insert(index, object);
}
 
void QQmlObjectModel::move(int from, int to, int n)
{
    Q_D(QQmlObjectModel);
    if (n <= 0 || from == to)
        return;
    if (from < 0 || to < 0 || from + n > count() || to + n > count()) {
        qmlWarning(this) << tr("move: out of range");
        return;
    }
    d->move(from, to, n);
}
 
void QQmlObjectModel::remove(int index, int n)
{
    Q_D(QQmlObjectModel);
    if (index < 0 || n <= 0 || index + n > count()) {
        qmlWarning(this) << tr("remove: indices [%1 - %2] out of range [0 - %3]").arg(index).arg(index+n).arg(count());
        return;
    }
    d->remove(index, n);
}
 
void QQmlObjectModel::clear()
{
    Q_D(QQmlObjectModel);
    d->clear();
}
 
bool QQmlInstanceModel::setRequiredProperty(int index, const QString &name, const QVariant &value)
{
    Q_UNUSED(index);
    Q_UNUSED(name);
    Q_UNUSED(value);
    // The view should not call this function, unless
    // it's actually handled in a subclass.
    Q_UNREACHABLE_RETURN(false);
}
 
QT_END_NAMESPACE
 
#include "moc_qqmlobjectmodel_p.cpp"