X-Git-Url: https://git.quassel-irc.org/?p=quassel.git;a=blobdiff_plain;f=src%2Fclient%2Ftreemodel.cpp;h=e456f6fda126fa3081e589b3e7910d41d2625741;hp=18f7c4fe3de9617951bce9954a1b7e3faa0fd2bb;hb=3a3e844f9fcfd12235a0086af75ecd503b621ef4;hpb=57ce4f437b29e538c80029d57f39efdbb9afb328

diff --git a/src/client/treemodel.cpp b/src/client/treemodel.cpp
index 18f7c4fe..e456f6fd 100644
--- a/src/client/treemodel.cpp
+++ b/src/client/treemodel.cpp
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2005-08 by the Quassel Project                          *
+ *   Copyright (C) 2005-2018 by the Quassel Project                        *
  *   devel@quassel-irc.org                                                 *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
@@ -15,460 +15,654 @@
  *   You should have received a copy of the GNU General Public License     *
  *   along with this program; if not, write to the                         *
  *   Free Software Foundation, Inc.,                                       *
- *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.         *
  ***************************************************************************/
 
 #include "treemodel.h"
 
+#include <QCoreApplication>
 #include <QDebug>
+#include <utility>
+
+#include "quassel.h"
+
+class RemoveChildLaterEvent : public QEvent
+{
+public:
+    RemoveChildLaterEvent(AbstractTreeItem *child) : QEvent(QEvent::User), _child(child) {};
+    inline AbstractTreeItem *child() { return _child; }
+private:
+    AbstractTreeItem *_child;
+};
+
 
 /*****************************************
  *  Abstract Items of a TreeModel
  *****************************************/
 AbstractTreeItem::AbstractTreeItem(AbstractTreeItem *parent)
-  : QObject(parent),
-    _parentItem(parent),
-    _flags(Qt::ItemIsSelectable | Qt::ItemIsEnabled)
+    : QObject(parent),
+    _flags(Qt::ItemIsSelectable | Qt::ItemIsEnabled),
+    _treeItemFlags(nullptr)
 {
 }
 
-AbstractTreeItem::~AbstractTreeItem() {
-  AbstractTreeItem *child;
-  foreach(int key, _childItems.keys()) {
-    QList<AbstractTreeItem *>::iterator iter = _childItems[key].begin();
-    while(iter != _childItems[key].end()) {
-      child = *iter;
-      iter = _childItems[key].erase(iter);
-      disconnect(child, 0, this, 0);
-      child->deleteLater();
-    }
-  }
+
+bool AbstractTreeItem::newChild(AbstractTreeItem *item)
+{
+    int newRow = childCount();
+    emit beginAppendChilds(newRow, newRow);
+    _childItems.append(item);
+    emit endAppendChilds();
+    return true;
 }
 
-quint64 AbstractTreeItem::id() const {
-  return (quint64)this;
+
+bool AbstractTreeItem::newChilds(const QList<AbstractTreeItem *> &items)
+{
+    if (items.isEmpty())
+        return false;
+
+    int nextRow = childCount();
+    int lastRow = nextRow + items.count() - 1;
+
+    emit beginAppendChilds(nextRow, lastRow);
+    _childItems << items;
+    emit endAppendChilds();
+
+    return true;
 }
 
-int AbstractTreeItem::defaultColumn() const {
-  // invalid QModelIndexes aka rootNodes get their Childs stuffed into column -1
-  // all others to 0
-  if(_parentItem == 0)
-    return -1;
-  else
-    return 0;
+
+bool AbstractTreeItem::removeChild(int row)
+{
+    if (row < 0 || childCount() <= row)
+        return false;
+
+    child(row)->removeAllChilds();
+    emit beginRemoveChilds(row, row);
+    AbstractTreeItem *treeitem = _childItems.takeAt(row);
+    delete treeitem;
+    emit endRemoveChilds();
+
+    checkForDeletion();
+
+    return true;
 }
 
-void AbstractTreeItem::appendChild(int column, AbstractTreeItem *item) {
-  if(!_childItems.contains(column)) {
-    _childItems[column] = QList<AbstractTreeItem *>();
-    _childHash[column] = QHash<quint64, AbstractTreeItem *>();
-  }
-  
-  _childItems[column].append(item);
-  _childHash[column][item->id()] = item;
 
-  connect(item, SIGNAL(destroyed()), this, SLOT(childDestroyed()));
+void AbstractTreeItem::removeAllChilds()
+{
+    const int numChilds = childCount();
+
+    if (numChilds == 0)
+        return;
+
+    AbstractTreeItem *child;
+
+    QList<AbstractTreeItem *>::iterator childIter;
+
+    childIter = _childItems.begin();
+    while (childIter != _childItems.end()) {
+        child = *childIter;
+        child->setTreeItemFlags(nullptr); // disable self deletion, as this would only fuck up consitency and the child gets deleted anyways
+        child->removeAllChilds();
+        ++childIter;
+    }
+
+    emit beginRemoveChilds(0, numChilds - 1);
+    childIter = _childItems.begin();
+    while (childIter != _childItems.end()) {
+        child = *childIter;
+        childIter = _childItems.erase(childIter);
+        delete child;
+    }
+    emit endRemoveChilds();
+
+    checkForDeletion();
 }
 
-void AbstractTreeItem::appendChild(AbstractTreeItem *child) {
-  appendChild(defaultColumn(), child);
+
+void AbstractTreeItem::removeChildLater(AbstractTreeItem *child)
+{
+    Q_ASSERT(child);
+    QCoreApplication::postEvent(this, new RemoveChildLaterEvent(child));
 }
 
-void AbstractTreeItem::removeChild(int column, int row) {
-  if(!_childItems.contains(column)
-     || _childItems[column].size() <= row)
-    return;
-  
-  AbstractTreeItem *treeitem = _childItems[column].value(row);
-  _childItems[column].removeAt(row);
-  _childHash[column].remove(_childHash[column].key(treeitem));
-  disconnect(treeitem, 0, this, 0);
-  treeitem->deleteLater();
+
+void AbstractTreeItem::customEvent(QEvent *event)
+{
+    if (event->type() != QEvent::User)
+        return;
+
+    event->accept();
+
+    RemoveChildLaterEvent *removeEvent = static_cast<RemoveChildLaterEvent *>(event);
+    int childRow = _childItems.indexOf(removeEvent->child());
+    if (childRow == -1)
+        return;
+
+    // since we are called asynchronously we have to recheck if the item in question still has no childs
+    if (removeEvent->child()->childCount())
+        return;
+
+    removeChild(childRow);
 }
 
-void AbstractTreeItem::removeChild(int row) {
-  removeChild(defaultColumn(), row);
+
+bool AbstractTreeItem::reParent(AbstractTreeItem *newParent)
+{
+    // currently we support only re parenting if the child that's about to be
+    // adopted does not have any children itself.
+    if (childCount() != 0) {
+        qDebug() << "AbstractTreeItem::reParent(): cannot reparent"  << this << "with children.";
+        return false;
+    }
+
+    int oldRow = row();
+    if (oldRow == -1)
+        return false;
+
+    emit parent()->beginRemoveChilds(oldRow, oldRow);
+    parent()->_childItems.removeAt(oldRow);
+    emit parent()->endRemoveChilds();
+
+    AbstractTreeItem *oldParent = parent();
+    setParent(newParent);
+
+    bool success = newParent->newChild(this);
+    if (!success)
+        qWarning() << "AbstractTreeItem::reParent(): failed to attach to new parent after removing from old parent! this:" << this << "new parent:" << newParent;
+
+    if (oldParent)
+        oldParent->checkForDeletion();
+
+    return success;
 }
 
-AbstractTreeItem *AbstractTreeItem::child(int column, int row) const {
-  if(!_childItems.contains(column)
-     || _childItems[column].size() <= row)
-    return 0;
-  else
-    return _childItems[column].value(row);
+
+AbstractTreeItem *AbstractTreeItem::child(int row) const
+{
+    if (childCount() <= row)
+        return nullptr;
+    else
+        return _childItems[row];
 }
 
-AbstractTreeItem *AbstractTreeItem::child(int row) const {
-  return child(defaultColumn(), row);
+
+int AbstractTreeItem::childCount(int column) const
+{
+    if (column > 0)
+        return 0;
+    else
+        return _childItems.count();
 }
 
-AbstractTreeItem *AbstractTreeItem::childById(int column, const uint &id) const {
-  if(!_childHash.contains(column)
-     || !_childHash[column].contains(id))
-    return 0;
-  else
-    return _childHash[column].value(id);
+
+int AbstractTreeItem::row() const
+{
+    if (!parent()) {
+        qWarning() << "AbstractTreeItem::row():" << this << "has no parent AbstractTreeItem as it's parent! parent is" << QObject::parent();
+        return -1;
+    }
+
+    int row_ = parent()->_childItems.indexOf(const_cast<AbstractTreeItem *>(this));
+    if (row_ == -1)
+        qWarning() << "AbstractTreeItem::row():" << this << "is not in the child list of" << QObject::parent();
+    return row_;
 }
 
-AbstractTreeItem *AbstractTreeItem::childById(const uint &id) const {
-  return childById(defaultColumn(), id);
+
+void AbstractTreeItem::dumpChildList()
+{
+    qDebug() << "==== Childlist for Item:" << this << "====";
+    if (childCount() > 0) {
+        AbstractTreeItem *child;
+        QList<AbstractTreeItem *>::const_iterator childIter = _childItems.constBegin();
+        while (childIter != _childItems.constEnd()) {
+            child = *childIter;
+            qDebug() << "Row:" << child->row() << child << child->data(0, Qt::DisplayRole);
+            ++childIter;
+        }
+    }
+    qDebug() << "==== End Of Childlist ====";
 }
 
-int AbstractTreeItem::childCount(int column) const {
-  if(!_childItems.contains(column))
-    return 0;
-  else
-    return _childItems[column].count();
+
+/*****************************************
+ * SimpleTreeItem
+ *****************************************/
+SimpleTreeItem::SimpleTreeItem(QList<QVariant> data, AbstractTreeItem *parent)
+    : AbstractTreeItem(parent),
+    _itemData(std::move(data))
+{
 }
 
-int AbstractTreeItem::childCount() const {
-  return childCount(defaultColumn());
+
+SimpleTreeItem::~SimpleTreeItem()
+{
+}
+
+
+QVariant SimpleTreeItem::data(int column, int role) const
+{
+    if (column >= columnCount() || role != Qt::DisplayRole)
+        return QVariant();
+    else
+        return _itemData[column];
 }
 
-int AbstractTreeItem::column() const {
-  if(!_parentItem)
-    return -1;
 
-  QHash<int, QList<AbstractTreeItem*> >::const_iterator iter = _parentItem->_childItems.constBegin();
-  while(iter != _parentItem->_childItems.constEnd()) {
-    if(iter.value().contains(const_cast<AbstractTreeItem *>(this)))
-      return iter.key();
-    iter++;
-  }
+bool SimpleTreeItem::setData(int column, const QVariant &value, int role)
+{
+    if (column > columnCount() || role != Qt::DisplayRole)
+        return false;
+
+    if (column == columnCount())
+        _itemData.append(value);
+    else
+        _itemData[column] = value;
 
-  // unable to find us o_O
-  return _parentItem->defaultColumn();
+    emit dataChanged(column);
+    return true;
 }
 
-int AbstractTreeItem::row() const {
-  if(!_parentItem)
-    return -1;
-  else
-    return _parentItem->_childItems[column()].indexOf(const_cast<AbstractTreeItem*>(this));
+
+int SimpleTreeItem::columnCount() const
+{
+    return _itemData.count();
 }
 
-AbstractTreeItem *AbstractTreeItem::parent() const {
-  return _parentItem;
+
+/*****************************************
+ * PropertyMapItem
+ *****************************************/
+PropertyMapItem::PropertyMapItem(AbstractTreeItem *parent)
+    : AbstractTreeItem(parent)
+{
 }
 
-Qt::ItemFlags AbstractTreeItem::flags() const {
-  return _flags;
+
+QVariant PropertyMapItem::data(int column, int role) const
+{
+    if (column >= columnCount())
+        return QVariant();
+
+    switch (role) {
+    case Qt::ToolTipRole:
+        return toolTip(column);
+    case Qt::DisplayRole:
+    case TreeModel::SortRole: // fallthrough, since SortRole should default to DisplayRole
+        return property(propertyOrder()[column].toLatin1());
+    default:
+        return QVariant();
+    }
 }
 
-void AbstractTreeItem::setFlags(Qt::ItemFlags flags) {
-  _flags = flags;
+
+bool PropertyMapItem::setData(int column, const QVariant &value, int role)
+{
+    if (column >= columnCount() || role != Qt::DisplayRole)
+        return false;
+
+    setProperty(propertyOrder()[column].toLatin1(), value);
+    emit dataChanged(column);
+    return true;
 }
 
-void AbstractTreeItem::childDestroyed() {
-  AbstractTreeItem *item = static_cast<AbstractTreeItem*>(sender());
 
-  if(!item) {
-    qWarning() << "AbstractTreeItem::childDestroyed() received null pointer!";
-    return;
-  }
+int PropertyMapItem::columnCount() const
+{
+    return propertyOrder().count();
+}
+
 
-  QHash<int, QList<AbstractTreeItem*> >::const_iterator iter = _childItems.constBegin();
-  int column, row = -1;
-  while(iter != _childItems.constEnd()) {
-    row = iter.value().indexOf(item);
-    if(row != -1) {
-      column = iter.key();
-      break;
-    }
-    iter++;
-  }
-
-  if(row == -1) {
-    qWarning() << "AbstractTreeItem::childDestroyed(): unknown Child died:" << item << "parent:" << this;
-    return;
-  }
-  
-  _childItems[column].removeAt(row);
-  _childHash[column].remove(_childHash[column].key(item));
-  emit childDestroyed(row);
-}
-  
 /*****************************************
- * SimpleTreeItem
+ * TreeModel
  *****************************************/
-SimpleTreeItem::SimpleTreeItem(const QList<QVariant> &data, AbstractTreeItem *parent)
-  : AbstractTreeItem(parent),
-    _itemData(data)
+TreeModel::TreeModel(const QList<QVariant> &data, QObject *parent)
+    : QAbstractItemModel(parent),
+    _childStatus(QModelIndex(), 0, 0, 0),
+    _aboutToRemoveOrInsert(false)
 {
+    rootItem = new SimpleTreeItem(data, nullptr);
+    connectItem(rootItem);
+
+    if (Quassel::isOptionSet("debugmodel")) {
+        connect(this, SIGNAL(rowsAboutToBeInserted(const QModelIndex &, int, int)),
+            this, SLOT(debug_rowsAboutToBeInserted(const QModelIndex &, int, int)));
+        connect(this, SIGNAL(rowsAboutToBeRemoved(const QModelIndex &, int, int)),
+            this, SLOT(debug_rowsAboutToBeRemoved(const QModelIndex &, int, int)));
+        connect(this, SIGNAL(rowsInserted(const QModelIndex &, int, int)),
+            this, SLOT(debug_rowsInserted(const QModelIndex &, int, int)));
+        connect(this, SIGNAL(rowsRemoved(const QModelIndex &, int, int)),
+            this, SLOT(debug_rowsRemoved(const QModelIndex &, int, int)));
+        connect(this, SIGNAL(dataChanged(const QModelIndex &, const QModelIndex &)),
+            this, SLOT(debug_dataChanged(const QModelIndex &, const QModelIndex &)));
+    }
 }
 
-SimpleTreeItem::~SimpleTreeItem() {
+
+TreeModel::~TreeModel()
+{
+    delete rootItem;
 }
 
-QVariant SimpleTreeItem::data(int column, int role) const {
-  if(role == Qt::DisplayRole && column < _itemData.count())
-    return _itemData[column];
-  else
-    return QVariant();
+
+AbstractTreeItem *TreeModel::root() const
+{
+    return rootItem;
 }
 
-int SimpleTreeItem::columnCount() const {
-  return _itemData.count();
+
+QModelIndex TreeModel::index(int row, int column, const QModelIndex &parent) const
+{
+    if (row < 0 || row >= rowCount(parent) || column < 0 || column >= columnCount(parent))
+        return QModelIndex();
+
+    AbstractTreeItem *parentItem;
+
+    if (!parent.isValid())
+        parentItem = rootItem;
+    else
+        parentItem = static_cast<AbstractTreeItem *>(parent.internalPointer());
+
+    AbstractTreeItem *childItem = parentItem->child(row);
+
+    if (childItem)
+        return createIndex(row, column, childItem);
+    else
+        return QModelIndex();
 }
 
-/*****************************************
- * PropertyMapItem
- *****************************************/
-PropertyMapItem::PropertyMapItem(const QStringList &propertyOrder, AbstractTreeItem *parent)
-  : AbstractTreeItem(parent),
-    _propertyOrder(propertyOrder)
+
+QModelIndex TreeModel::indexByItem(AbstractTreeItem *item) const
 {
+    if (item == nullptr) {
+        qWarning() << "TreeModel::indexByItem(AbstractTreeItem *item) received NULL-Pointer";
+        return QModelIndex();
+    }
+
+    if (item == rootItem)
+        return QModelIndex();
+    else
+        return createIndex(item->row(), 0, item);
 }
 
-PropertyMapItem::PropertyMapItem(AbstractTreeItem *parent)
-  : AbstractTreeItem(parent),
-    _propertyOrder(QStringList())
+
+QModelIndex TreeModel::parent(const QModelIndex &index) const
 {
+    if (!index.isValid()) {
+        // ModelTest does this
+        // qWarning() << "TreeModel::parent(): has been asked for the rootItems Parent!";
+        return QModelIndex();
+    }
+
+    AbstractTreeItem *childItem = static_cast<AbstractTreeItem *>(index.internalPointer());
+    AbstractTreeItem *parentItem = childItem->parent();
+
+    Q_ASSERT(parentItem);
+    if (parentItem == rootItem)
+        return QModelIndex();
+
+    return createIndex(parentItem->row(), 0, parentItem);
 }
 
 
-PropertyMapItem::~PropertyMapItem() {
+int TreeModel::rowCount(const QModelIndex &parent) const
+{
+    AbstractTreeItem *parentItem;
+    if (!parent.isValid())
+        parentItem = rootItem;
+    else
+        parentItem = static_cast<AbstractTreeItem *>(parent.internalPointer());
+
+    return parentItem->childCount(parent.column());
 }
-  
-QVariant PropertyMapItem::data(int column, int role) const {
-  if(column >= columnCount())
-    return QVariant();
 
-  if(role != Qt::DisplayRole)
-    return QVariant();
 
-  return property(_propertyOrder[column].toAscii());
+int TreeModel::columnCount(const QModelIndex &parent) const
+{
+    Q_UNUSED(parent)
+    return rootItem->columnCount();
+    // since there the Qt Views don't draw more columns than the header has columns
+    // we can be lazy and simply return the count of header columns
+    // actually this gives us more freedom cause we don't have to ensure that a rows parent
+    // has equal or more columns than that row
+
+//   AbstractTreeItem *parentItem;
+//   if(!parent.isValid())
+//     parentItem = rootItem;
+//   else
+//     parentItem = static_cast<AbstractTreeItem*>(parent.internalPointer());
+//   return parentItem->columnCount();
 }
 
-int PropertyMapItem::columnCount() const {
-  return _propertyOrder.count();
+
+QVariant TreeModel::data(const QModelIndex &index, int role) const
+{
+    if (!index.isValid())
+        return QVariant();
+
+    AbstractTreeItem *item = static_cast<AbstractTreeItem *>(index.internalPointer());
+    return item->data(index.column(), role);
 }
-  
-void PropertyMapItem::appendProperty(const QString &property) {
-  _propertyOrder << property;
+
+
+bool TreeModel::setData(const QModelIndex &index, const QVariant &value, int role)
+{
+    if (!index.isValid())
+        return false;
+
+    AbstractTreeItem *item = static_cast<AbstractTreeItem *>(index.internalPointer());
+    return item->setData(index.column(), value, role);
 }
 
 
+Qt::ItemFlags TreeModel::flags(const QModelIndex &index) const
+{
+    if (!index.isValid()) {
+        return rootItem->flags() & Qt::ItemIsDropEnabled;
+    }
+    else {
+        AbstractTreeItem *item = static_cast<AbstractTreeItem *>(index.internalPointer());
+        return item->flags();
+    }
+}
+
 
-/*****************************************
- * TreeModel
- *****************************************/
-TreeModel::TreeModel(const QList<QVariant> &data, QObject *parent)
-  : QAbstractItemModel(parent)
+QVariant TreeModel::headerData(int section, Qt::Orientation orientation, int role) const
+{
+    if (orientation == Qt::Horizontal && role == Qt::DisplayRole)
+        return rootItem->data(section, role);
+    else
+        return QVariant();
+}
+
+
+void TreeModel::itemDataChanged(int column)
+{
+    AbstractTreeItem *item = qobject_cast<AbstractTreeItem *>(sender());
+    QModelIndex leftIndex, rightIndex;
+
+    if (item == rootItem)
+        return;
+
+    if (column == -1) {
+        leftIndex = createIndex(item->row(), 0, item);
+        rightIndex = createIndex(item->row(), item->columnCount() - 1, item);
+    }
+    else {
+        leftIndex = createIndex(item->row(), column, item);
+        rightIndex = leftIndex;
+    }
+
+    emit dataChanged(leftIndex, rightIndex);
+}
+
+
+void TreeModel::connectItem(AbstractTreeItem *item)
 {
-  rootItem = new SimpleTreeItem(data, 0);
+    connect(item, SIGNAL(dataChanged(int)),
+        this, SLOT(itemDataChanged(int)));
+
+    connect(item, SIGNAL(beginAppendChilds(int, int)),
+        this, SLOT(beginAppendChilds(int, int)));
+    connect(item, SIGNAL(endAppendChilds()),
+        this, SLOT(endAppendChilds()));
+
+    connect(item, SIGNAL(beginRemoveChilds(int, int)),
+        this, SLOT(beginRemoveChilds(int, int)));
+    connect(item, SIGNAL(endRemoveChilds()),
+        this, SLOT(endRemoveChilds()));
 }
 
-TreeModel::~TreeModel() {
-  delete rootItem;
+
+void TreeModel::beginAppendChilds(int firstRow, int lastRow)
+{
+    AbstractTreeItem *parentItem = qobject_cast<AbstractTreeItem *>(sender());
+    if (!parentItem) {
+        qWarning() << "TreeModel::beginAppendChilds(): cannot append Children to unknown parent";
+        return;
+    }
+
+    QModelIndex parent = indexByItem(parentItem);
+    Q_ASSERT(!_aboutToRemoveOrInsert);
+
+    _aboutToRemoveOrInsert = true;
+    _childStatus = ChildStatus(parent, rowCount(parent), firstRow, lastRow);
+    beginInsertRows(parent, firstRow, lastRow);
 }
 
-QModelIndex TreeModel::index(int row, int column, const QModelIndex &parent) const {
-  if(!hasIndex(row, column, parent))
-    return QModelIndex();
-  
-  AbstractTreeItem *parentItem;
-  
-  if(!parent.isValid())
-    parentItem = rootItem;
-  else
-    parentItem = static_cast<AbstractTreeItem*>(parent.internalPointer());
-  
-  AbstractTreeItem *childItem = parentItem->child(parent.column(), row);
 
-  if(childItem)
-    return createIndex(row, column, childItem);
-  else
-    return QModelIndex();
+void TreeModel::endAppendChilds()
+{
+    AbstractTreeItem *parentItem = qobject_cast<AbstractTreeItem *>(sender());
+    if (!parentItem) {
+        qWarning() << "TreeModel::endAppendChilds(): cannot append Children to unknown parent";
+        return;
+    }
+    Q_ASSERT(_aboutToRemoveOrInsert);
+    ChildStatus cs = _childStatus;
+#ifndef QT_NO_DEBUG
+    QModelIndex parent = indexByItem(parentItem);
+    Q_ASSERT(cs.parent == parent);
+    Q_ASSERT(rowCount(parent) == cs.childCount + cs.end - cs.start + 1);
+#endif
+    _aboutToRemoveOrInsert = false;
+    for (int i = cs.start; i <= cs.end; i++) {
+        connectItem(parentItem->child(i));
+    }
+    endInsertRows();
 }
 
-QModelIndex TreeModel::indexById(uint id, const QModelIndex &parent) const {
-  AbstractTreeItem *parentItem; 
-  
-  if(!parent.isValid())
-    parentItem = rootItem;
-  else
+
+void TreeModel::beginRemoveChilds(int firstRow, int lastRow)
+{
+    AbstractTreeItem *parentItem = qobject_cast<AbstractTreeItem *>(sender());
+    if (!parentItem) {
+        qWarning() << "TreeModel::beginRemoveChilds(): cannot append Children to unknown parent";
+        return;
+    }
+
+    for (int i = firstRow; i <= lastRow; i++) {
+        disconnect(parentItem->child(i), nullptr, this, nullptr);
+    }
+
+    // consitency checks
+    QModelIndex parent = indexByItem(parentItem);
+    Q_ASSERT(firstRow <= lastRow);
+    Q_ASSERT(parentItem->childCount() > lastRow);
+    Q_ASSERT(!_aboutToRemoveOrInsert);
+    _aboutToRemoveOrInsert = true;
+    _childStatus = ChildStatus(parent, rowCount(parent), firstRow, lastRow);
+
+    beginRemoveRows(parent, firstRow, lastRow);
+}
+
+
+void TreeModel::endRemoveChilds()
+{
+    AbstractTreeItem *parentItem = qobject_cast<AbstractTreeItem *>(sender());
+    if (!parentItem) {
+        qWarning() << "TreeModel::endRemoveChilds(): cannot remove Children from unknown parent";
+        return;
+    }
+
+    // concistency checks
+    Q_ASSERT(_aboutToRemoveOrInsert);
+#ifndef QT_NO_DEBUG
+    ChildStatus cs = _childStatus;
+    QModelIndex parent = indexByItem(parentItem);
+    Q_ASSERT(cs.parent == parent);
+    Q_ASSERT(rowCount(parent) == cs.childCount - cs.end + cs.start - 1);
+#endif
+    _aboutToRemoveOrInsert = false;
+
+    endRemoveRows();
+}
+
+
+void TreeModel::clear()
+{
+    rootItem->removeAllChilds();
+}
+
+
+void TreeModel::debug_rowsAboutToBeInserted(const QModelIndex &parent, int start, int end)
+{
+    qDebug() << "debug_rowsAboutToBeInserted" << parent << parent.internalPointer() << parent.data().toString() << rowCount(parent) << start << end;
+}
+
+
+void TreeModel::debug_rowsAboutToBeRemoved(const QModelIndex &parent, int start, int end)
+{
+    AbstractTreeItem *parentItem;
     parentItem = static_cast<AbstractTreeItem *>(parent.internalPointer());
-  
-  AbstractTreeItem *childItem = parentItem->childById(parent.column(), id);
-  
-  if(childItem)
-    return createIndex(childItem->row(), 0, childItem);
-  else
-    return QModelIndex();
-}
-
-QModelIndex TreeModel::indexByItem(AbstractTreeItem *item) const {
-  if(item == 0) {
-    qWarning() << "TreeModel::indexByItem(AbstractTreeItem *item) received NULL-Pointer";
-    return QModelIndex();
-  }
-  
-  if(item == rootItem)
-    return QModelIndex();
-  else
-    return createIndex(item->row(), 0, item);
-
-}
-
-QModelIndex TreeModel::parent(const QModelIndex &index) const {
-  if(!index.isValid())
-    return QModelIndex();
-  
-  AbstractTreeItem *childItem = static_cast<AbstractTreeItem *>(index.internalPointer());
-  AbstractTreeItem *parentItem = static_cast<AbstractTreeItem *>(childItem->parent());
-  
-  if(parentItem == rootItem)
-    return QModelIndex();
-  
-  return createIndex(parentItem->row(), 0, parentItem);
-}
-
-int TreeModel::rowCount(const QModelIndex &parent) const {
-  AbstractTreeItem *parentItem;
-  if(!parent.isValid())
-    parentItem = rootItem;
-  else
-    parentItem = static_cast<AbstractTreeItem*>(parent.internalPointer());
-
-  return parentItem->childCount(parent.column());
-}
-
-int TreeModel::columnCount(const QModelIndex &parent) const {
-  Q_UNUSED(parent)
-  // since there the Qt Views don't draw more columns than the header has columns
-  // we can be lazy and simply return the count of header columns
-  // actually this gives us more freedom cause we don't have to ensure that a rows parent
-  // has equal or more columns than that row
-  
-//   if(parent.isValid()) {
-//     AbstractTreeItem *child;
-//     if(child = static_cast<AbstractTreeItem *>(parent.internalPointer())->child(parent.column(), parent.row()))
-//       return child->columnCount();
-//     else
-//       return static_cast<AbstractTreeItem*>(parent.internalPointer())->columnCount();
-//   } else {
-//     return rootItem->columnCount();
-//   }
-
-  return rootItem->columnCount();
-}
-
-QVariant TreeModel::data(const QModelIndex &index, int role) const {
-  if(!index.isValid())
-    return QVariant();
-
-  AbstractTreeItem *item = static_cast<AbstractTreeItem*>(index.internalPointer());
-  return item->data(index.column(), role);
-}
-
-Qt::ItemFlags TreeModel::flags(const QModelIndex &index) const {
-  AbstractTreeItem *item;
-  if(!index.isValid())
-    item = rootItem;
-  else
-    item = static_cast<AbstractTreeItem *>(index.internalPointer());
-  return item->flags();
-}
-
-QVariant TreeModel::headerData(int section, Qt::Orientation orientation, int role) const {
-  if (orientation == Qt::Horizontal && role == Qt::DisplayRole)
-    return rootItem->data(section, role);
-  else
-    return QVariant();
-}
-
-void TreeModel::itemDataChanged(int column) {
-  AbstractTreeItem *item = qobject_cast<AbstractTreeItem *>(sender());
-  QModelIndex leftIndex, rightIndex;
-
-  if(item == rootItem)
-    return;
-
-  if(column == -1) {
-    leftIndex = createIndex(item->row(), 0, item);
-    rightIndex = createIndex(item->row(), item->columnCount()-1, item);
-  } else {
-    leftIndex = createIndex(item->row(), column, item);
-    rightIndex = leftIndex;
-  }
-
-  emit dataChanged(leftIndex, rightIndex);
-}
-
-void TreeModel::appendChild(AbstractTreeItem *parent, AbstractTreeItem *child) {
-  if(parent == 0 or child == 0) {
-    qWarning() << "TreeModel::appendChild(parent, child) parent and child have to be valid pointers!" << parent << child;
-    return;
-  }
-
-  int nextRow = parent->childCount();
-  beginInsertRows(indexByItem(parent), nextRow, nextRow);
-  parent->appendChild(child);
-  endInsertRows();
-
-  connect(child, SIGNAL(dataChanged(int)),
-	  this, SLOT(itemDataChanged(int)));
-  
-  connect(child, SIGNAL(newChild(AbstractTreeItem *)),
-	  this, SLOT(newChild(AbstractTreeItem *)));
-
-  connect(child, SIGNAL(childDestroyed(int)),
-	  this, SLOT(childDestroyed(int)));
-}
-
-void TreeModel::newChild(AbstractTreeItem *child) {
-  appendChild(static_cast<AbstractTreeItem *>(sender()), child);
+    if (!parentItem)
+        parentItem = rootItem;
+    qDebug() << "debug_rowsAboutToBeRemoved" << parent << parentItem << parent.data().toString() << rowCount(parent) << start << end;
+
+    QModelIndex child;
+    for (int i = end; i >= start; i--) {
+        child = parent.child(i, 0);
+        Q_ASSERT(parentItem->child(i));
+        qDebug() << ">>>" << i << child << child.data().toString();
+    }
 }
 
-void TreeModel::childDestroyed(int row) {
-  QModelIndex parent = indexByItem(static_cast<AbstractTreeItem *>(sender()));
-  beginRemoveRows(parent, row, row);
-  endRemoveRows();
-}
-
-bool TreeModel::removeRow(int row, const QModelIndex &parent) {
-  if(row > rowCount(parent))
-    return false;
-  
-  AbstractTreeItem *item;
-  if(!parent.isValid())
-    item = rootItem;
-  else
-    item = static_cast<AbstractTreeItem*>(parent.internalPointer());
-  
-  beginRemoveRows(parent, row, row);
-  item->removeChild(parent.column(), row);
-  endRemoveRows();
-  return true;
+
+void TreeModel::debug_rowsInserted(const QModelIndex &parent, int start, int end)
+{
+    AbstractTreeItem *parentItem;
+    parentItem = static_cast<AbstractTreeItem *>(parent.internalPointer());
+    if (!parentItem)
+        parentItem = rootItem;
+    qDebug() << "debug_rowsInserted:" << parent << parentItem << parent.data().toString() << rowCount(parent) << start << end;
+
+    QModelIndex child;
+    for (int i = start; i <= end; i++) {
+        child = parent.child(i, 0);
+        Q_ASSERT(parentItem->child(i));
+        qDebug() << "<<<" << i << child << child.data().toString();
+    }
 }
 
-bool TreeModel::removeRows(int row, int count, const QModelIndex &parent) {
-  // check if there is work to be done
-  if(count == 0)
-    return true;
 
-  // out of range check
-  if(row + count - 1 > rowCount(parent) || row < 0 || count < 0) 
-    return false;
-  
-  AbstractTreeItem *item;
-  if(!parent.isValid())
-    item = rootItem;
-  else
-    item = static_cast<AbstractTreeItem *>(parent.internalPointer());
-  
-  
-  beginRemoveRows(parent, row, row + count - 1);
-
-  for(int i = row + count - 1; i >= 0; i--) {
-    item->removeChild(parent.column(), i);
-  }
-  endRemoveRows();
-  return true;
-}
-
-void TreeModel::clear() {
-  removeRows(0, rowCount());
-  reset();
+void TreeModel::debug_rowsRemoved(const QModelIndex &parent, int start, int end)
+{
+    qDebug() << "debug_rowsRemoved" << parent << parent.internalPointer() << parent.data().toString() << rowCount(parent) << start << end;
+}
+
+
+void TreeModel::debug_dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight)
+{
+    qDebug() << "debug_dataChanged" << topLeft << bottomRight;
+    QStringList displayData;
+    for (int row = topLeft.row(); row <= bottomRight.row(); row++) {
+        displayData = QStringList();
+        for (int column = topLeft.column(); column <= bottomRight.column(); column++) {
+            displayData << data(topLeft.sibling(row, column), Qt::DisplayRole).toString();
+        }
+        qDebug() << "  row:" << row << displayData;
+    }
 }