QAbstractListModel problem

[UltimatePace]

The documentation specifically mentions returning an empty QVariant rather than returning 0 so I'd hope it wouldn't be that.

Running the same code but using a QTableView instead calls with role values of 6, 7, 9, 10, 1, 0 and 8. I reckon it might actually be something weird going on with the QListView. I wonder if maybe the Jambi implementation requires me to trigger something that the QTableView doesn't?

Thanks for your help with this. I think it might be worth seeing whether I can contact the Qt developers and logging a bug report or something. I've managed to find myself a work-around for now, it's not ideal but it's not too clunky and just avoids the QListView control.

[l8night]

I had a very similar issue with QAbstractListModel in C++ (the code I tried was the same (but in C++)) I found a solution by looking at the source of QStringListModel.
my working C++ test class looks like:

class MyModel : public QAbstractListModel
{
    public:
    MyModel( QObject * parent ) : QAbstractListModel(parent) {}
    int rowCount( const QModelIndex & parent ) const
    {
        // we are a list, so if there is a parent return 0 (see the Qt source of QStringListModel)
        if (parent.isValid())
            return 0;
        return 4; // we have 4 rows
    }
 
    QVariant data( const QModelIndex & index, int role /* = Qt::DisplayRole*/ ) const
    {
        // if an invalid row, return empty QVariant
        if (index.row() < 0 || index.row() >= 4)
            return QVariant();
 
        switch( role )
        {
        case Qt::DisplayRole:
        case Qt::EditRole:
            {
                QString s;
                s = QString("row [%1]").arg( index.row() );
                return QVariant(s);
            }
        default:
            return QVariant();
        }
    }
};

class MyModel : public QAbstractListModel
{
    public:
    MyModel( QObject * parent ) : QAbstractListModel(parent) {}
    int rowCount( const QModelIndex & parent ) const
    {
        // we are a list, so if there is a parent return 0 (see the Qt source of QStringListModel)
        if (parent.isValid())
            return 0;
        return 4; // we have 4 rows
    }

    QVariant data( const QModelIndex & index, int role /* = Qt::DisplayRole*/ ) const
    {
        // if an invalid row, return empty QVariant
        if (index.row() < 0 || index.row() >= 4)
            return QVariant();

        switch( role )
        {
        case Qt::DisplayRole:
        case Qt::EditRole:
            {
                QString s;
                s = QString("row [%1]").arg( index.row() );
                return QVariant(s);
            }
        default:
            return QVariant();
        }
    }
};

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I believe that it is the 0 returned if the parent is valid from `rowCount` is what you need to do, if I just returned 4 in all cases I get no list displayed.
Hope this solves your issue.