How can i sort an alphanumeric string in abstract table view

manikandan

Hi, am new to QT. I am using a QAbstractTableModel for displaying some file information. One of the column contains size of the file. If the size is maintained as double[without any unit like Kb, Mb, Gb] then sorting works fine with the following code

class MyModel : public QAbstractTableModel   
{
...
...
}

QSortFilterProxyModel *proxyModel = new QSortFilterProxyModel(this);
proxyModel->setSourceModel( myModel );
ui->tableView->setModel( proxyModel );

But when i try to maintain the file size in human readable format[with units Kb, Mb, Gb] then i changed double to QString and then sorting is not in proper order. I know that sorting of strings work based on ASCII values but how can i achieve proper sorting for this case?

PS: I tried implementing lessthan function on my own, but faced ambiguity error because of QAbstractTableModel and QSortFilterProxyModel

Chris Kawa

Hi, welcome to the forum.

No need to implement string sorting. It will be slow and is unnecessary. This is a good use case for user roles in a model.
Make the model return a decorated string value for Qt::DisplayRole and the original double value for some custom role (e.g. Qt::UserRole). Then set the sorting role in the proxy model like this: proxyModel->setSortRole(Qt::UserRole); and you should be good to go. Displayed will be the string but for sorting the original double value will be used.

Btw. surround code with ``` to make it format better (I corrected your post).

manikandan

Thank you Chris...It works :)