advice on using QDataWidgetMapper in QtSql

[schnitzel]

I have two tables: address and unit
unit table contains a field called 'AddressID'

address table contains primary key 'AddressID'

One address can occupy one ore more units.

The unit datawidget mapper is configure like this:

model = new QSqlTableModel;
    model->setTable("unit");
    model->setEditStrategy(QSqlTableModel::OnManualSubmit);
    model->select();
 
    mapper = new QDataWidgetMapper(this);
    mapper->setModel(model);
    mapper->addMapping(ui->le_Unit, model->fieldIndex("UnitName"));
    mapper->addMapping(ui->le_AddressID, model->fieldIndex("AddressID"));
    mapper->addMapping(ui->le_UnitID,model->fieldIndex("UnitID"));
 
    connect(ui->pb_Prev,SIGNAL(clicked()),mapper, SLOT(toPrevious()));
    connect(ui->pb_Next,SIGNAL(clicked()),mapper, SLOT(toNext()));
    connect(mapper,SIGNAL(currentIndexChanged(int)),this,SLOT(mapperChanged(int)));

model = new QSqlTableModel;
    model->setTable("unit");
    model->setEditStrategy(QSqlTableModel::OnManualSubmit);
    model->select();

    mapper = new QDataWidgetMapper(this);
    mapper->setModel(model);
    mapper->addMapping(ui->le_Unit, model->fieldIndex("UnitName"));
    mapper->addMapping(ui->le_AddressID, model->fieldIndex("AddressID"));
    mapper->addMapping(ui->le_UnitID,model->fieldIndex("UnitID"));

    connect(ui->pb_Prev,SIGNAL(clicked()),mapper, SLOT(toPrevious()));
    connect(ui->pb_Next,SIGNAL(clicked()),mapper, SLOT(toNext()));
    connect(mapper,SIGNAL(currentIndexChanged(int)),this,SLOT(mapperChanged(int)));

To copy to clipboard, switch view to plain text mode 

The Address data widget mapper is configured like this:

addrmodel = new QSqlTableModel;
    addrmodel->setTable("addresses");
    addrmodel->setEditStrategy(QSqlTableModel::OnManualSubmit);
    addrmodel->select();
    addrMapper = new QDataWidgetMapper(this);
    addrMapper->setModel(addrmodel);
    addrMapper->addMapping(ui->le_AID,addrmodel->fieldIndex("AddressID"));
    addrMapper->addMapping(ui->le_FirstName,addrmodel->fieldIndex("FirstName"));
    addrMapper->addMapping(ui->le_LastName,addrmodel->fieldIndex("LastName"));

addrmodel = new QSqlTableModel;
    addrmodel->setTable("addresses");
    addrmodel->setEditStrategy(QSqlTableModel::OnManualSubmit);
    addrmodel->select();
    addrMapper = new QDataWidgetMapper(this);
    addrMapper->setModel(addrmodel);
    addrMapper->addMapping(ui->le_AID,addrmodel->fieldIndex("AddressID"));
    addrMapper->addMapping(ui->le_FirstName,addrmodel->fieldIndex("FirstName"));
    addrMapper->addMapping(ui->le_LastName,addrmodel->fieldIndex("LastName"));

To copy to clipboard, switch view to plain text mode 

In addition to this, I have a combo box where I have added all the unit name and unit id from the unit table so I can jump to any unit by calling mapperChanged with the index of the combo box.

This all works great, I can jump to any unit. My goal is to show the matching address and the only way I can make it work is like this:

for(int row = 0; row < addrmodel->rowCount(); row++)
    {
        QSqlRecord record = addrmodel->record(row);
        if(record.value(0).toInt() == ui->le_AddressID->text().toInt())
        {
            addrMapper->setCurrentIndex(row);
            break;
        }
 
    }

for(int row = 0; row < addrmodel->rowCount(); row++)
    {
        QSqlRecord record = addrmodel->record(row);
        if(record.value(0).toInt() == ui->le_AddressID->text().toInt())
        {
            addrMapper->setCurrentIndex(row);
            break;
        }

    }

To copy to clipboard, switch view to plain text mode 

However, this doesn't seem that efficient and I was hoping I could simply filter the addrmodel instead :

addrmodel->setFilter("AddressID='" + ui->le_AddressID->text() + "'");

addrmodel->setFilter("AddressID='" + ui->le_AddressID->text() + "'");

To copy to clipboard, switch view to plain text mode 

But the addrMapper doesn't update. What am I doing wrong?

Is there a way to find the index of the model after the filter has been applied?

[ChrisW67]

According to the QDataWidgetMapper docs:

Every time the current index changes, each widget is updated with data from the model via the property specified when its mapping was made.

I am guessing that changing (resetting) the underlying model is not changing the mapper's idea of the current index so it is not updating. Try a QDataWidgetMapper::toFirst() or QDataWidgetMapper::setCurrentIndex() to force it to think again.

[schnitzel]

According to the QDataWidgetMapper docs: I am guessing that changing (resetting) the underlying model is not changing the mapper's idea of the current index so it is not updating. Try a QDataWidgetMapper::toFirst() or QDataWidgetMapper::setCurrentIndex() to force it to think again.

You are right, this seems to work fine:

addrmodel->setFilter("AddressID='" + ui->le_AddressID->text() + "'");
    addrMapper->toFirst();

addrmodel->setFilter("AddressID='" + ui->le_AddressID->text() + "'");
    addrMapper->toFirst();

To copy to clipboard, switch view to plain text mode 

thanks for the tip