QDateEdit and date returned

[cydside]

Hi to All,
I'm using a QDateEdit widget to edit date values from a database, so I display date values as "dd/MM/yyyy" (settting displayFormat). When I finish to update the record the QDateEdit widget returns "yyyy-MM-dd" formtat. Is there a way to change the return value?
Thanks.

[spirit]

try to set display format using setDisplayFormat.

[cydside]

The method setDisplayFormat doesn't work, QDateEdit returns the same formatted value "dd-MM-yyyy"!!!

[spirit]

QDateEdit returns QDate, if you need to convert date to string then use QDate::toString with format==dd/MM/yyyy.

[cydside]

I'm trying to set the format value returned because QDateEdit widget is mapped to a QSqlTableModel!!!

[spirit]

I don't understand what do you want.
can you attach compilable example?

[cydside]

The following code show you how I'm using the QDateEdit widget:

frmEntUsc_AME::frmEntUsc_AME(QSqlRelationalTableModel *model,
   const int &isItNew, QWidget *parent) : QDialog(parent)
{
   ui.setupUi(this);
   this->setWindowFlags(Qt::Dialog | Qt::MSWindowsFixedSizeDialogHint);
   this->setAttribute(Qt::WA_DeleteOnClose);
 
   modelAME = new QSqlTableModel(this);
   modelAME = model;
 
   modelAME->database().transaction();
 
   if (isItNew < 0)
   {
      id = modelAME->rowCount();
      modelAME->insertRow(id);
      ui.dedData->setDate(QDate::currentDate());
   }
   else
   {
      id = isItNew;
   }
 
   ui.dedData->setDisplayFormat("dd/MM/yyyy"); //QDateEdit widget
 
   mapper = new QDataWidgetMapper(this);
   mapper->setModel(modelAME);
   mapper->setItemDelegate(new QSqlRelationalDelegate(this));
   mapper->setSubmitPolicy(QDataWidgetMapper::ManualSubmit);
   //...
   //...
   mapper->addMapping(ui.dedData, 9); // the QDateEdit widget is mapped to a date field
   mapper->setCurrentIndex(id);
 
   connect(ui.btnAnnulla, SIGNAL(clicked()), this, SLOT(revert()));
   connect(ui.btnOk, SIGNAL(clicked()), this, SLOT(submit()));
 
   qDebug() << "frmEntUsc_AME Loaded!";
}

frmEntUsc_AME::frmEntUsc_AME(QSqlRelationalTableModel *model,
   const int &isItNew, QWidget *parent) : QDialog(parent)
{
   ui.setupUi(this);
   this->setWindowFlags(Qt::Dialog | Qt::MSWindowsFixedSizeDialogHint);
   this->setAttribute(Qt::WA_DeleteOnClose);

   modelAME = new QSqlTableModel(this);
   modelAME = model;

   modelAME->database().transaction();

   if (isItNew < 0)
   {
      id = modelAME->rowCount();
      modelAME->insertRow(id);
      ui.dedData->setDate(QDate::currentDate());
   }
   else
   {
      id = isItNew;
   }

   ui.dedData->setDisplayFormat("dd/MM/yyyy"); //QDateEdit widget

   mapper = new QDataWidgetMapper(this);
   mapper->setModel(modelAME);
   mapper->setItemDelegate(new QSqlRelationalDelegate(this));
   mapper->setSubmitPolicy(QDataWidgetMapper::ManualSubmit);
   //...
   //...
   mapper->addMapping(ui.dedData, 9); // the QDateEdit widget is mapped to a date field
   mapper->setCurrentIndex(id);

   connect(ui.btnAnnulla, SIGNAL(clicked()), this, SLOT(revert()));
   connect(ui.btnOk, SIGNAL(clicked()), this, SLOT(submit()));

   qDebug() << "frmEntUsc_AME Loaded!";
}

To copy to clipboard, switch view to plain text mode 

[spirit]

which date format do you use in a database?

[cydside]

I'm using a SQLITE database, the field is declared as TEXT!

[spirit]

why? why is not date?

[cydside]

As you know, SQLITE allow only few datatype :

• NULL
• INTEGER
• REAL
• TEXT
• BLOB

[spirit]

yes, forgot about that.

[cydside]

So, I'm right to claim that there isn't a way to set up the return value for a QDateEdit widget!

[spirit]

I made a test and data in QDateEdit sets normal, but mask in sql-table changed to another.

[ChrisW67]

I realise I'm a bit late into this thread but I found it looking for solutions to similar issues with Sqlite "dates". Maybe this post will be useful to others.

Sqlite will treat text in an ISO date format as a date for the purposes of its date functions. However, when it reports the data in the "date" column to Qt you end up with a QVariant::String. Some Qt components recognise the ISO date string and treat it as a date, some don't. I'd like everything to have the best chance of just doing the Right Thing. How I am tackling this is to create a model sub-class that overrides data() to convert the QVariant::String to QVariant::Date on relevant columns:

QVariant MyTableModel::data ( const QModelIndex & item, int role ) const
{
    // Default return value
    QVariant ret =  QSqlTableModel::data(item, role);
 
    // Convert date column into real date type
    if (role == Qt::EditRole || role == Qt::DisplayRole)
        if (item.column() == dateIssued)
            if (ret.canConvert(QVariant::Date))
                ret.convert(QVariant::Date);
 
    return ret;
}

QVariant MyTableModel::data ( const QModelIndex & item, int role ) const
{
    // Default return value
    QVariant ret =  QSqlTableModel::data(item, role);

    // Convert date column into real date type
    if (role == Qt::EditRole || role == Qt::DisplayRole)
        if (item.column() == dateIssued)
            if (ret.canConvert(QVariant::Date))
                ret.convert(QVariant::Date);

    return ret;
}

To copy to clipboard, switch view to plain text mode 

I'm still pondering whether I need to do something with setData() for these columns, but at the moment it doesn't seem to be needed. I end up with an ISO date in the column if I pass setData() a QVariant::Date.

[wysota]

The proper way of handling such situations is to provide a custom delegate for the widget mapper with setModelData() and setEditorData() reimplemented.

[ChrisW67]

I'm not sure why you would opt to change every view on the data in the model in order to apply a delegate rather than change the model in one place and allow Qt's default date handling to kick in. Is this just a preference thing, or is there some deep-seated principle that I am missing?

[wysota]

The functionality of the model is correct. We have a requirement on the display of the data thus the straight way to fulfilling it is to correct the view related to it. Of course you can also do it by subclassing the model or by applying a model proxy, it's all up to you and depends on the effect you want to obtain.