An update on this from my side:

My initial approach wasn't flawless, as @VRonin pointed out, because QAbstractItemModel::columnCount didn't return the appropriate values. I've fixed this, by not immediately passing the new count after inserting the elements to a list, of which the size was used, but instead have the model save exactly how many categories it currently accounts for, so the connection looks like this:

connect(item_registry.get(), &item_registry::category_added, [this](int position, QSharedPointer<category>) { beginInsertColumns(QModelIndex{}, position, position); _current_category_count++; endInsertColumns(); });

and likewise columnCount:

int item_model::columnCount(QModelIndex const&) const { if(!_register) { qCritical() << "Item-model didn't have a register"; return 0; } return 1 /* name */ + _current_category_count; }

Can we finally see where and how you emit dataChanged()? And with which indexes?

From the looks of it, you have to re-create the models when you change these settings.

@JonB, thanks, i will try your implementation.

@corianderop Hi I am also stuck in a similar situation did you figure out a solution for it ?

@Kofr
mapFromSource() and mapToSource() are enough. The default implementation should depend on these methods only.

Someone on stackoverflow was kind enough to point out my error. My parent method() should have been:

QModelIndex MyModel::parent(const QModelIndex &index) const { if (!index.isValid()) { return QModelIndex(); } QObject *item = (QObject *)index.internalPointer(); Directory *parentItem = qobject_cast<Directory *>(item->parent()); if (!parentItem || parentItem == invisibleTopLevelDirectory()) { return QModelIndex(); } Directory *parentOfParentItem = qobject_cast<Directory *>(parentItem->parent()); if (!parentOfParentItem) { return QModelIndex(); } int listIndex = parentOfParentItem->indexOfItem(parentItem); if (listIndex < 0) { return QModelIndex(); } else { return createIndex(listIndex, index.column(), parentItem); } }

@jpnurmi cool :)
did some first tests with QAbstractListModel filled with some Customer* (QObject)
inserted customers, removed customers, changed properties via C++
all correct refreshed in QML ListView

seems I can "port" most of my data model logic / UI from BlackBerry Cascades to Qt 5.6 :)

I've managed to solve the problem by first adding a second property to the Components, so now the Component has this at the top:

Component { id: frameworkHeaderElement Rectangle { property var modelData: [] property var propData: [] ... } ... }

Then when the Component is Loaded during the Loader I've changed the onLoaded function to the following:

onLoaded: { item.modelData = model item.propData = storiesModel.get(index) }

Now I can access my index using modelData, and I can access all of my properties (which may be unique to a Component) through propData as follows

text: propData.headerText

I'm sure there's a better way to solve this, but for the time being this works just fine for what I need.

Thanks for your help!