For the record, this was a perfectly good question. The QAbstractItemModel::createIndex() docs do not state that it embeds a model pointer into the index it creates, nor do the QModelIndex docs mention the private constructor that makes it possible.

This makes QModelIndex::parent() look suspicious if you happen to be troubleshooting a problem. If you want to be sure your model is implemented correctly, you have to put aside the docs and dig up the inline function definitions in qabstractitemmodel.h.

Thank you @mrjj and @Christian for answer. I am able to make user Checkable.

class CustomListModel : public QStandardItemModel {
public:
Qt::ItemFlags CustomListModel::flags(const QModelIndex & index) const {
Qt::ItemFlags defaultFlags = QStandardItemModel::flags(index);
if (index.isValid()) {
return defaultFlags | Qt::ItemIsUserCheckable;
}
return defaultFlags;
}

CustomListModel(const int row, const int coloumn) : QStandardItemModel(row, coloumn) { }

};

and modification.
hwListProxyModel->setSourceModel(new CustomListModel (0, 0));

@michelson said:
Hello,

I assumed i had to reimplement QItemDelegate::setModelData(...)

I think this should suffice for your case. You can of course always create your own model as @SGaist suggested. As for your request for additional material:

Here is an overview of the model-view framework A simple spinbox delegate example Icons example that uses delagets

I hope this helps.
Kind regards.

Hi,

internalPointer() is basically used when you use createIndex().
As I said the internal structure is not specified in the documentation; so if you want to understand the exact implementation you have to have a look in the Qt sources