QTableView and QSortFilterProxyModel

[SPlatten]

I am using QTableView, I was originally using just QStnadardItemModel, now I've implemented QSortFilterProxyModel.

mpsfpTmodel = new QSortFilterProxyModel(this);
mpsiTmodel = new QStandardItemModel(this);
mpsfpTmodel->setSourceModel(mpsiTmodel);
mptvTrecs = new QTableView(this);
mptvTrecs->setSelectionBehavior(QAbstractItemView::SelectRows);
mptvTrecs->setMinimumWidth(cintThreatsTableWidth);
mptvTrecs->setModel(mpsfpTmodel);
mptvTrecs->setSortingEnabled(true);

The problem I'm having is that the columns contain numbers and these do not sort correctly.

How do I fix this?

[raven-worx]

@SPlatten
for this you have to subclass.

The cleaner solution would be to ensure the source data is already in the correct type.

You could also add a custom ItemRole to your source model and call QSortFilterProxyModel::setSortRole() with that new custom role. In the source model then return the data in the correct type for that role.

[mchinand]

What's the source of your data in your model and how is your model created? It looks like they are being added to your model as text/strings instead of numbers.

[SPlatten]

@mchinand , the data is read from MariaDB then in the application I process the query and append each record to the model mpsiTmodel. How do I add to the model as numbers?

[raven-worx]

@SPlatten said in QTableView and QSortFilterProxyModel:

How do I fix this?

probably they are stored as strings and not integers?!

Override QSortFilterProxyModel::lessThan():

bool MySortFilterProxyModel::lessThan(const QModelIndex &source_left, const QModelIndex &source_right) const
{
     if( source_left.column() == MY_COLUMN && source_right.column() == MY_COLUMN )
         return source_left.data().toInt() < source_right.data().toInt();

    return QSortFilterProxyModel::lessThan(source_left,source_right);
}

[SPlatten]

@raven-worx , thank you, is it possible to implement that function in a parent class or is the only way to sub-class QSortFilterProxyModel ?

[raven-worx]

@SPlatten
for this you have to subclass.

The cleaner solution would be to ensure the source data is already in the correct type.

You could also add a custom ItemRole to your source model and call QSortFilterProxyModel::setSortRole() with that new custom role. In the source model then return the data in the correct type for that role.

[SGaist]

Hi,

Out of curiosity, how are you filling your model ?
If these values are stored as numerical value in your database, you should retrieve and store them in a similar fashion so no need for any kind of subclassing.

[SPlatten]

@SGaist , I've sorted out this problem now, I'm not in front of the laptop I was using, so I will post an update tomorrow when I'm back in front of it.

[Seb Tur]

@SPlatten
What I do is I make sure to cast to numbers and no nulls in the query
eg. SELECT CAST(IFNULL(kompletacja,0) AS DECIMAL(10,5)) as 'kompletacja' FROM TABLE