qtreewidget.cpp

奇趣公司比较新的qt/emd版本

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#include "qtreewidget.h"

#ifndef QT_NO_TREEWIDGET
#include <qheaderview.h>
#include <qpainter.h>
#include <qitemdelegate.h>
#include <qstack.h>
#include <qdebug.h>
#include <private/qtreeview_p.h>
#include <private/qwidgetitemdata_p.h>
#include <private/qtreewidget_p.h>
#include <private/qtreewidgetitemiterator_p.h>

// workaround for VC++ 6.0 linker bug (?)
typedef bool(*LessThan)(const QPair<QTreeWidgetItem*,int>&,const QPair<QTreeWidgetItem*,int>&);

class QTreeModelLessThan
{
public:
    inline bool operator()(QTreeWidgetItem *i1, QTreeWidgetItem *i2) const
        { return *i1 < *i2; }
};

class QTreeModelGreaterThan
{
public:
    inline bool operator()(QTreeWidgetItem *i1, QTreeWidgetItem *i2) const
        { return *i2 < *i1; }
};

/*
    \class QTreeModel
    \brief The QTreeModel class manages the items stored in a tree view.

    \ingroup model-view
    \mainclass
*/

/*!
    \enum QTreeWidgetItem::ChildIndicatorPolicy
    \since 4.3

    \value ShowIndicator
    \value DontShowIndicator
    \value DontShowIndicatorWhenChildless
*/

/*!
    \fn void QTreeWidgetItem::setDisabled(bool disabled)
    \since 4.3

    Disables the item if \a disabled is true; otherwise enables the item.

    \sa setFlags()
*/

/*!
    \fn bool QTreeWidgetItem::isDisabled() const
    \since 4.3

    Returns true if the item is disabled; otherwise returns false.

    \sa setFlags()
*/

/*!
  \internal

  Constructs a tree model with a \a parent object and the given
  number of \a columns.
*/

QTreeModel::QTreeModel(int columns, QTreeWidget *parent)
    : QAbstractItemModel(parent), rootItem(new QTreeWidgetItem),
      headerItem(new QTreeWidgetItem), sortPending(false)
{
    rootItem->view = parent;
    headerItem->view = parent;
    setColumnCount(columns);
}

/*!
  \internal

*/

QTreeModel::QTreeModel(QTreeModelPrivate &dd, QTreeWidget *parent)
    : QAbstractItemModel(dd, parent), rootItem(new QTreeWidgetItem),
      headerItem(new QTreeWidgetItem), sortPending(false)
{
    rootItem->view = parent;
    headerItem->view = parent;
}

/*!
  \internal

  Destroys this tree model.
*/

QTreeModel::~QTreeModel()
{
    clear();
    delete headerItem;
    rootItem->view = 0;
    delete rootItem;
}

/*!
  \internal

  Removes all items in the model.
*/

void QTreeModel::clear()
{
    for (int i = 0; i < rootItem->childCount(); ++i) {
        QTreeWidgetItem *item = rootItem->children.at(i);
        item->par = 0;
        item->view = 0;
        delete item;
    }
    rootItem->children.clear();
    sortPending = false;
    reset();
}

/*!
  \internal

  Sets the number of \a columns in the tree model.
*/

void QTreeModel::setColumnCount(int columns)
{
    if (columns < 0)
        return;
    if (!headerItem) {
        headerItem = new QTreeWidgetItem();
        headerItem->view = view();
    }
    int count = columnCount();
    if (count == columns)
        return;

    if (columns < count) {
        beginRemoveColumns(QModelIndex(), columns, count - 1);
        headerItem->values.resize(columns);
        endRemoveColumns();
    } else {
        beginInsertColumns(QModelIndex(), count, columns - 1);
        headerItem->values.resize(columns);
        for (int i = count; i < columns; ++i) {// insert data without emitting the dataChanged signal
            headerItem->values[i].append(QWidgetItemData(Qt::DisplayRole, QString::number(i + 1)));
            headerItem->d->display.append(QString::number(i + 1));
        }
        endInsertColumns();
    }
}

/*!
  \internal

  Returns the tree view item corresponding to the \a index given.

  \sa QModelIndex
*/

QTreeWidgetItem *QTreeModel::item(const QModelIndex &index) const
{
    if (!index.isValid())
        return 0;
    return static_cast<QTreeWidgetItem*>(index.internalPointer());
}

/*!
  \internal

  Returns the model index that refers to the
  tree view \a item and \a column.
*/

QModelIndex QTreeModel::index(const QTreeWidgetItem *item, int column) const
{
    if (!item || (item == rootItem))
        return QModelIndex();
    const QTreeWidgetItem *par = item->parent();
    QTreeWidgetItem *itm = const_cast<QTreeWidgetItem*>(item);
    if (!par)
        par = rootItem;
    const int row = par->children.lastIndexOf(itm);
    return createIndex(row, column, itm);
}

/*!
  \internal
  \reimp

  Returns the model index with the given \a row,
  \a column and \a parent.
*/

QModelIndex QTreeModel::index(int row, int column, const QModelIndex &parent) const
{
    int c = columnCount(parent);
    if (row < 0 || column < 0 || column >= c)
        return QModelIndex();

    QTreeWidgetItem *parentItem = parent.isValid() ? item(parent) : rootItem;
    if (parentItem && row < parentItem->childCount()) {
        QTreeWidgetItem *itm = parentItem->child(row);
        if (itm)
            return createIndex(row, column, itm);
        return QModelIndex();
    }

    return QModelIndex();
}

/*!
  \internal
  \reimp

  Returns the parent model index of the index given as
  the \a child.
*/

QModelIndex QTreeModel::parent(const QModelIndex &child) const
{
    if (!child.isValid())
        return QModelIndex();
    QTreeWidgetItem *itm = static_cast<QTreeWidgetItem *>(child.internalPointer());
    if (!itm)
        return QModelIndex();
    QTreeWidgetItem *parent = itm->parent();
    return index(parent, 0);
}

/*!
  \internal
  \reimp

  Returns the number of rows in the \a parent model index.
*/

int QTreeModel::rowCount(const QModelIndex &parent) const
{
    executePendingSort();

    if (!parent.isValid())
        return rootItem->childCount();

    QTreeWidgetItem *parentItem = item(parent);
    if (parentItem)
        return parentItem->childCount();
    return 0;
}

/*!
  \internal
  \reimp

  Returns the number of columns in the item referred to by
  the given \a index.
*/

int QTreeModel::columnCount(const QModelIndex &index) const
{
    Q_UNUSED(index);
    if (!headerItem)
        return 0;
    return headerItem->columnCount();
}

bool QTreeModel::hasChildren(const QModelIndex &parent) const
{
    executePendingSort();

    if (!parent.isValid())
        return (rootItem->childCount() > 0);

    QTreeWidgetItem *itm = item(parent);
    if (!itm)
        return false;
    switch (itm->d->policy) {
    case QTreeWidgetItem::ShowIndicator:
        return true;
    case QTreeWidgetItem::DontShowIndicator:
        return false;
    case QTreeWidgetItem::DontShowIndicatorWhenChildless:
        return (itm->childCount() > 0);
    }
    return false;
}

/*!
  \internal
  \reimp

  Returns the data corresponding to the given model \a index
  and \a role.
*/

QVariant QTreeModel::data(const QModelIndex &index, int role) const
{
    if (!index.isValid())
        return QVariant();
    QTreeWidgetItem *itm = item(index);
    if (itm)
        return itm->data(index.column(), role);
    return QVariant();
}

/*!
  \internal
  \reimp

  Sets the data for the item specified by the \a index and \a role
  to that referred to by the \a value.

  Returns true if successful; otherwise returns false.
*/

bool QTreeModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
    if (!index.isValid())
        return false;
    QTreeWidgetItem *itm = item(index);
    if (itm) {
        itm->setData(index.column(), role, value);
        return true;
    }
    return false;
}

QMap<int, QVariant> QTreeModel::itemData(const QModelIndex &index) const
{
    QMap<int, QVariant> roles;
    QTreeWidgetItem *itm = item(index);
    if (itm) {
        int column = index.column();
        if (column < itm->values.count()) {
            for (int i = 0; i < itm->values.at(column).count(); ++i) {
                roles.insert(itm->values.at(column).at(i).role,
                             itm->values.at(column).at(i).value);
            }
        }

        // the two special cases
        QVariant displayValue = itm->data(column, Qt::DisplayRole);
        if (displayValue.isValid())
            roles.insert(Qt::DisplayRole, displayValue);

        QVariant checkValue = itm->data(column, Qt::CheckStateRole);
        if (checkValue.isValid())
            roles.insert(Qt::CheckStateRole, checkValue);
    }
    return roles;
}

/*!
  \internal
  \reimp
*/
bool QTreeModel::insertRows(int row, int count, const QModelIndex &parent)
{
    if (count < 1 || row < 0 || row > rowCount(parent) || parent.column() > 0)
        return false;

    beginInsertRows(parent, row, row + count - 1);
    QTreeWidgetItem *par = item(parent);
    while (count > 0) {
        QTreeWidgetItem *item = new QTreeWidgetItem();
        item->view = view();
        item->par = par;
        if (par)
            par->children.insert(row++, item);
        else
            rootItem->children.insert(row++, item);
        --count;
    }
    endInsertRows();
    return true;
}

/*!
  \internal
  \reimp
*/
bool QTreeModel::insertColumns(int column, int count, const QModelIndex &parent)
{
    if (count < 1 || column < 0 || column > columnCount(parent) || parent.column() > 0 || !headerItem)
        return false;

    beginInsertColumns(parent, column, column + count - 1);

    int oldCount = columnCount(parent);
    column = qBound(0, column, oldCount);
    headerItem->values.resize(oldCount + count);
    for (int i = oldCount; i < oldCount + count; ++i) {
        headerItem->values[i].append(QWidgetItemData(Qt::DisplayRole, QString::number(i + 1)));
        headerItem->d->display.append(QString::number(i + 1));
    }

    QStack<QTreeWidgetItem*> itemstack;
    itemstack.push(0);
    while (!itemstack.isEmpty()) {
        QTreeWidgetItem *par = itemstack.pop();
        QList<QTreeWidgetItem*> children = par ? par->children : rootItem->children;
        for (int row = 0; row < children.count(); ++row) {
            QTreeWidgetItem *child = children.at(row);
            if (child->children.count())
                itemstack.push(child);
            child->values.insert(column, count, QVector<QWidgetItemData>());
        }
    }