qtreewidget.cpp

奇趣公司比较新的qt/emd版本

            values.reserve(model->headerItem->columnCount());
            model->executePendingSort();
        }
    }
}

/*!
    Constructs a tree widget item and append it to the given \a parent.

    \sa type()
*/
QTreeWidgetItem::QTreeWidgetItem(QTreeWidgetItem *parent, int type)
    : rtti(type), view(0), d(new QTreeWidgetItemPrivate(this)), par(0),
      itemFlags(Qt::ItemIsSelectable
                |Qt::ItemIsUserCheckable
                |Qt::ItemIsEnabled
                |Qt::ItemIsDragEnabled
                |Qt::ItemIsDropEnabled)
{
    if (parent)
        parent->addChild(this);
     if (view) {
        QTreeModel *model = ::qobject_cast<QTreeModel*>(view->model());
        if (model) {
            model->executePendingSort();
        }
    }
}

/*!
    Constructs a tree widget item and append it to the given \a parent.
    The given list of \a strings will be set as the item text for each column in the item.

    \sa type()
*/
QTreeWidgetItem::QTreeWidgetItem(QTreeWidgetItem *parent, const QStringList &strings, int type)
    : rtti(type), view(0), d(new QTreeWidgetItemPrivate(this)), par(0),
      itemFlags(Qt::ItemIsSelectable
                |Qt::ItemIsUserCheckable
                |Qt::ItemIsEnabled
                |Qt::ItemIsDragEnabled
                |Qt::ItemIsDropEnabled)
{
    for (int i = 0; i < strings.count(); ++i)
        setText(i, strings.at(i));
    if (parent)
        parent->addChild(this);
     if (view) {
        QTreeModel *model = ::qobject_cast<QTreeModel*>(view->model());
        if (model) {
            model->executePendingSort();
        }
    }
}

/*!
    \fn QTreeWidgetItem::QTreeWidgetItem(QTreeWidgetItem *parent, QTreeWidgetItem *preceding, int type)

    Constructs a tree widget item of the specified \a type that is inserted
    into the \a parent after the \a preceding child item.

    \sa type()
*/
QTreeWidgetItem::QTreeWidgetItem(QTreeWidgetItem *parent, QTreeWidgetItem *after, int type)
    : rtti(type), view(0), d(new QTreeWidgetItemPrivate(this)), par(0),
      itemFlags(Qt::ItemIsSelectable
                |Qt::ItemIsUserCheckable
                |Qt::ItemIsEnabled
                |Qt::ItemIsDragEnabled
                |Qt::ItemIsDropEnabled)
{
    if (parent) {
        int i = parent->indexOfChild(after) + 1;
        parent->insertChild(i, this);
    }
    if (view) {
        QTreeModel *model = ::qobject_cast<QTreeModel*>(view->model());
        if (model) {
            model->executePendingSort();
        }
    }
}

/*!
  Destroys this tree widget item.
*/

QTreeWidgetItem::~QTreeWidgetItem()
{
    QTreeModel *model = (view ? ::qobject_cast<QTreeModel*>(view->model()) : 0);
    if (par) {
        int i = par->children.indexOf(this);
        if (i >= 0) {
            if (model) model->beginRemoveItems(par, i, 1);
            // users _could_ do changes when connected to rowsAboutToBeRemoved,
            // so we check again to make sure 'i' is valid
            if (!par->children.isEmpty() && par->children.at(i) == this)
                par->children.takeAt(i);
            if (model) model->endRemoveItems();
        }
    } else if (model) {
        if (this == model->headerItem) {
            model->headerItem = 0;
        } else {
            int i = model->rootItem->children.indexOf(this);
            if (i >= 0) {
                model->beginRemoveItems(0, i, 1);
                // users _could_ do changes when connected to rowsAboutToBeRemoved,
                // so we check again to make sure 'i' is valid
                if (!model->rootItem->children.isEmpty() && model->rootItem->children.at(i) == this)
                    model->rootItem->children.takeAt(i);
                model->endRemoveItems();
            }
        }
    }
    // at this point the persistent indexes for the children should also be invalidated
    // since we invalidated the parent
    for (int i = 0; i < children.count(); ++i) {
        QTreeWidgetItem *child = children.at(i);
        // make sure the child does not try to remove itself from our children list
        child->par = 0;
        // make sure the child does not try to remove itself from the top level list
        child->view = 0;
        delete child;
    }

    children.clear();
    delete d;
}

/*!
    Creates a deep copy of the item and of its children.
*/
QTreeWidgetItem *QTreeWidgetItem::clone() const
{
    QTreeWidgetItem *copy = 0;

    QStack<const QTreeWidgetItem*> stack;
    QStack<QTreeWidgetItem*> parentStack;
    stack.push(this);
    parentStack.push(0);

    QTreeWidgetItem *root = 0;
    const QTreeWidgetItem *item = 0;
    QTreeWidgetItem *parent = 0;
    while (!stack.isEmpty()) {
        // get current item, and copied parent
        item = stack.pop();
        parent = parentStack.pop();

        // copy item
        copy = new QTreeWidgetItem(*item);
        if (!root)
            root = copy;

        // set parent and add to parents children list
        if (parent) {
            copy->par = parent;
            parent->children.insert(0, copy);
        }

        for (int i = 0; i < item->childCount(); ++i) {
            stack.push(item->child(i));
            parentStack.push(copy);
        }
    }
    return root;
}

/*!
   Sets the item indicator \a policy. This policy decides when the
   tree branch expand/collapse indicator is shown.
   The default value is ShowForChildren.

   \sa childIndicatorPolicy()
*/
void QTreeWidgetItem::setChildIndicatorPolicy(QTreeWidgetItem::ChildIndicatorPolicy policy)
{
    if (d->policy == policy)
        return;
    d->policy = policy;
    if (QTreeModel *model = (view ? ::qobject_cast<QTreeModel*>(view->model()) : 0))
        view->update(model->index(this, 0));
}

/*!
   Returns the item indicator policy. This policy decides when the
   tree branch expand/collapse indicator is shown.

   \sa setChildIndicatorPolicy()
*/
QTreeWidgetItem::ChildIndicatorPolicy QTreeWidgetItem::childIndicatorPolicy() const
{
    return d->policy;
}

/*!
    \fn void QTreeWidgetItem::setFlags(Qt::ItemFlags flags)

    Sets the flags for the item to the given \a flags. These determine whether
    the item can be selected or modified.  This is often used to disable an item.

    \sa flags()
*/
void QTreeWidgetItem::setFlags(Qt::ItemFlags flags)
{
    const bool enable = (flags & Qt::ItemIsEnabled);
    const bool changedState = bool(itemFlags & Qt::ItemIsEnabled) != enable;
    const bool changedExplicit = d->disabled != !enable;

    d->disabled = !enable;

    if (enable && par && !(par->itemFlags & Qt::ItemIsEnabled)) // inherit from parent
        itemFlags = flags & ~Qt::ItemIsEnabled;
    else // this item is explicitly disabled or has no parent
        itemFlags = flags;

    if (changedState && changedExplicit) { // if the propagate the change to the children
        QStack<QTreeWidgetItem*> parents;
        parents.push(this);
        while (!parents.isEmpty()) {
            QTreeWidgetItem *parent = parents.pop();
            for (int i = 0; i < parent->children.count(); ++i) {
                QTreeWidgetItem *child = parent->children.at(i);
                if (!child->d->disabled) { // if not explicitly disabled
                    parents.push(child);
                    if (enable)
                        child->itemFlags = child->itemFlags | Qt::ItemIsEnabled;
                    else
                        child->itemFlags = child->itemFlags & ~Qt::ItemIsEnabled;
                    child->itemChanged(); // ### we may want to optimize this
                }
            }
        }
    }
    itemChanged();
}

void QTreeWidgetItemPrivate::propagateDisabled(QTreeWidgetItem *item)
{
    Q_ASSERT(item);
    const bool enable = item->par ? (item->par->itemFlags.testFlag(Qt::ItemIsEnabled)) : true;

    QStack<QTreeWidgetItem*> parents;
    parents.push(item);
    while (!parents.isEmpty()) {
        QTreeWidgetItem *parent = parents.pop();
        if (!parent->d->disabled) { // if not explicitly disabled
            if (enable)
                parent->itemFlags = parent->itemFlags | Qt::ItemIsEnabled;
            else
                parent->itemFlags = parent->itemFlags & ~Qt::ItemIsEnabled;
            parent->itemChanged(); // ### we may want to optimize this
        }

        for (int i = 0; i < parent->children.count(); ++i) {
            QTreeWidgetItem *child = parent->children.at(i);
            parents.push(child);
        }
    }
}
/*!
    \fn Qt::ItemFlags QTreeWidgetItem::flags() const

    Returns the flags used to describe the item. These determine whether
    the item can be checked, edited, and selected.

    The default value for flags is
    Qt::ItemIsSelectable | Qt::ItemIsUserCheckable | Qt::ItemIsEnabled | Qt::ItemIsDragEnabled.
    If the item was constructed with a parent, flags will in addition contain Qt::ItemIsDropEnabled.

    \sa setFlags()
*/
Qt::ItemFlags QTreeWidgetItem::flags() const
{
    return itemFlags;
}

/*!
    Sets the value for the item's \a column and \a role to the given
    \a value.

    The \a role describes the type of data specified by \a value, and is defined by
    the Qt::ItemDataRole enum.
*/
void QTreeWidgetItem::setData(int column, int role, const QVariant &value)
{
    if (column < 0)
        return;

    QTreeModel *model = (view ? ::qobject_cast<QTreeModel*>(view->model()) : 0);
    switch (role) {
    case Qt::EditRole:
    case Qt::DisplayRole: {
        if (values.count() <= column) {
            if (model && this == model->headerItem)
                model->setColumnCount(column + 1);
            else
                values.resize(column + 1);
        }
        if (d->display.count() <= column) {
            for (int i = d->display.count() - 1; i < column - 1; ++i)
                d->display.append(QVariant());
            d->display.append(value);
        } else if (d->display[column] != value) {
            d->display[column] = value;
        } else {
            return; // value is unchanged
        }
    } break;
    case Qt::CheckStateRole:
        if (itemFlags & Qt::ItemIsTristate) {
            for (int i = 0; i < children.count(); ++i) {
                QTreeWidgetItem *child = children.at(i);
                if (child->data(column, role).isValid()) {// has a CheckState
                    Qt::ItemFlags f = itemFlags; // a little hack to avoid multiple dataChanged signals
                    itemFlags &= ~Qt::ItemIsTristate;
                    child->setData(column, role, value);
                    itemFlags = f;
                }
            }
        }
        // Don't break, but fall through
    default:
        if (column < values.count()) {
            bool found = false;
            QVector<QWidgetItemData> column_values = values.at(column);
            for (int i = 0; i < column_values.count(); ++i) {
                if (column_values.at(i).role == role) {
                    if (column_values.at(i).value == value)
                        return; // value is unchanged
                    values[column][i].value = value;
                    found = true;
                    break;
                }
            }
            if (!found)
                values[column].append(QWidgetItemData(role, value));
        } else {
            if (model && this == model->headerItem)
                model->setColumnCount(column + 1);
            else
                values.resize(column + 1);
            values[column].append(QWidgetItemData(role, value));
        }
    }

    if (model) {
        model->emitDataChanged(this, column);
        if (role == Qt::CheckStateRole) {
            QTreeWidgetItem *p;
            for (p = par; p && (p->itemFlags & Qt::ItemIsTristate); p = p->par)
                model->emitDataChanged(p, column);
        }
    }
}

/*!
    Returns the value for the item's \a column and \a role.
*/
QVariant QTreeWidgetItem::data(int column, int role) const
{
    switch (role) {
    case Qt::EditRole:
    case Qt::DisplayRole:
        if (column >= 0 && column < d->display.count())
            return d->display.at(column);
        break;
    case Qt::CheckStateRole:
        // special case for check state in tristate
        if (children.count() && (itemFlags & Qt::ItemIsTristate))
            return childrenCheckState(column);
   default:
        if (column >= 0 && column < values.size()) {
            const QVector<QWidgetItemData> &column_values = values.at(column);
            for (int i = 0; i < column_values.count(); ++i)
                if (column_values.at(i).role == role)
                    return column_values.at(i).value;
        }
    }
    return QVariant();
}

/*!
  Returns true if the text in the item is less than the text in the
  \a other item, otherwise returns false.
*/

bool QTreeWidgetItem::operator<(const QTreeWidgetItem &other) const
{
    int column = view ? view->sortColumn() : 0;
    return text(column) < other.text(column);
}

#ifndef QT_NO_DATASTREAM

/*!
    Reads the item from stream \a in. This only reads data into a single item.

    \sa write()
*/
void QTreeWidgetItem::read(QDataStream &in)
{
    // convert from streams written before we introduced display (4.2.0)
    if (in.version() < QDataStream::Qt_4_2) {
        d->display.clear();
        in >> values;
        // move the display value over to the display string list
        for (int column = 0; column < values.count(); ++column) {
            d->display << QVariant();
            for (int i = 0; i < values.at(column).count(); ++i) {
                if (values.at(column).at(i).role == Qt::DisplayRole) {
                    d->display[column] = values.at(column).at(i).value;
                    values[column].remove(i--);
                }
            }
        }
    } else {
        in >> values >> d->display;
    }
}

/*!
    Writes the item to stream \a out. This only writes data from one single item.

    \sa read()
*/
void QTreeWidgetItem::write(QDataStream &out) const
{
    out << values << d->display;
}

/*!
    \since 4.1

    Constructs a copy of \a other. Note that type() and treeWidget()
    are not copied.

    This function is useful when reimplementing clone().

    \sa data(), flags()
*/
QTreeWidgetItem::QTreeWidgetItem(const QTreeWidgetItem &other)
    : rtti(Type), values(other.values), view(0),
      d(new QTreeWidgetItemPrivate(this)), par(0),
      itemFlags(other.itemFlags)
{
    d->display = other.d->display;
}

/*!
    Assigns \a other's data and flags to this item. Note that type()
    and treeWidget() are not copied.