Signal dataChanged of QAbstractTableModel doesnot work in QT5

I have a tableview in my program. It always works very well in QT4. As you will not fix the bug:
https://bugreports.qt.io/browse/QTBUG-44722

I have to update my project to QT5
And there is a new problem with this code:

void TableModel::updateData(int i) // child class of QAbstractTableModel
{
    if (i<0) return;
    QModelIndex t1 = index(i, 0); 
    QModelIndex t2 = index(i, 5);
     qDebug() << "111_____TableModel::updateData " << i;
    emit dataChanged(t1, t2); 
}

It should update the data of table of GUI, but it doesnot work in QT5.
Even I write like this:

void TableModel::updateData(int i)
{
	if (i<0) return;
    QModelIndex t1 = index(i, 0); 
    QModelIndex t2 = index(i, 5);
    qDebug() << "111_____TableModel::updateData " << i;

    QVector<int> qq;
    qq.append(Qt::DisplayRole);
    qq.append(Qt::DecorationRole);
    qq.append(Qt::EditRole);
    qq.append(Qt::ToolTipRole);
    qq.append(Qt::StatusTipRole);
    qq.append(Qt::WhatsThisRole);
    qq.append(Qt::SizeHintRole);
    qq.append(Qt::AccessibleTextRole);
    qq.append(Qt::AccessibleDescriptionRole);
    qq.append(Qt::UserRole);
    emit dataChanged(t1, t2, qq);
}

It doesnot work too.
-----------------------------------------------------
The correct logic is:
I call TableModel::updateData(int i) to emit dataChanged(t1, t2, qq); , and then QT will call QStyledItemDelegate::paint() (this function has be overrided by my child class) to paint the table of GUI. But now the 2nd step will not be executed.Why?

I guess maybe QT5 forget the connection of signal dataChanged and QStyledItemDelegate::paint() ?

Finally, I test the code above in QT5.11/5.32/5.41, there is the same problem. Can you help me to confirm this is the bug of QT5? Thanks in advance.