[Interest] Issue with QSortFilterProxyModel and Delegate

[David Boosalis]

Hope someone can help me here.  I have a QTableView for which I use my own
QSortFilterProxyModel and own Delegate which is based on
QStyledItemDelegate.  My issue is in the Delegates::paintEvent()
I get core dumps if I have the following (Not using a proxy filter it works
by the way):

void DataDelegate::paint(QPainter *painter,
             const QStyleOptionViewItem &option,
             const QModelIndex &index) const
{
  QStandardItem *item = 0;
  if (!index.isValid()) {
    qWarning() << "Invalid index" << __FILE__ << __LINE__;
    return;
  }
 QStyledItemDelegate::paint(painter,option,index);
 QStandardItemModel *m = (QStandardItemModel *) index.model();
  bool isWatched    =  index.data(Qt::UserRole+4).toBool();
  if ( (isWatched) && (index.column() == 0))  {
    item = (QStandardItem *) m->itemFromIndex(index);  // <---------------
CORE DUMPS HERE------------------
    if (!item) {
      return;
    }
   .// continue to do some custom painting...
------------------------------------------------------------------------------------------------------------------------

Now if I do something like this:
void DataDelegate::paint(QPainter *painter,
             const QStyleOptionViewItem &option,
             const QModelIndex &proxyIndex) const
{
  QStandardItem *item = 0;
  if (!proxyIndex.isValid()) {
    qWarning() << "Invalid proxy index" << __FILE__ << __LINE__;
    return;
  }
  QStyledItemDelegate::paint(painter,option,proxyIndex);
  if (!proxyFilter) {  // store in Delegate class and is pointer to a class
derived from QSortFilterProxyModel
    qWarning() << "Invalid model for data delegate" << __FILE__ << __LINE__;
    return;
  }
 QModelIndex index = proxyFilter->mapToSource(proxyIndex);
  if (!index.isValid()) {
    // qWarning() << "Invalid index for data delegate" << __FILE__ <<
__LINE__;
    return;
  }
  QStandardItemModel *m = (QStandardItemModel *) index.model();
  bool isWatched    =  index.data(Qt::UserRole+4).toBool();
  if ( (isWatched) && (index.column() == 0))  {
    item = (QStandardItem *) m->itemFromIndex(index); //
    if (!item) {
      return;
    }
   // continue to do some custom painting....


This works, with the following ugly exception.  I get a lot of run time
warnings
" QSortFilterProxy Model: index from wrong model passed to mapToSource"

Despite these warnings I doI get my custom painting to occur.  I would like
to figure out a way to do it right so that I do not get thousands of these
warning messages at runitme.

Any suggestions on how to properly do a Delegate::paint() on a QTableView
with a custom QSortFilterProxyModel is greatly appreciated.


-David
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