i have met strange issue with QSortFilterProxyModel. i've simplified my code to reflect this issue. suppose, we have a custom item model:
Qt Code: 
  1. #define COL_CNT 7
  2.  
  3. class CustomModel : public QAbstractItemModel
  4. {
  5.     Q_OBJECT
  6. public:
  7.     explicit CustomModel(QObject *parent = 0) :
  9.     {
  10.         for(int i = 0; i < COL_CNT; ++i)
  11.             cnt << 0;
  12.         startTimer(1000);
  13.     }
  14.     QModelIndex index(int row, int column, const QModelIndex &parent = QModelIndex()) const
  15.     {
  16.         if(!parent.isValid())
  17.             return createIndex(row, column);
  18.         else
  19.             return QModelIndex();
  20.     }
  21.     QModelIndex parent(const QModelIndex &child) const
  22.     {
  23.         Q_UNUSED(child);
  24.         return QModelIndex();
  25.     }
  26.     int rowCount(const QModelIndex &parent = QModelIndex()) const
  27.     {
  28.         if(!parent.isValid())
  29.             return 1;
  30.         else
  31.             return 0;
  32.     }
  33.     int columnCount(const QModelIndex &parent = QModelIndex()) const
  34.     {
  35.         Q_UNUSED(parent);
  36.         return COL_CNT;
  37.     }
  38.     QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const
  39.     {
  40.         Q_UNUSED(index);
  41.         if(role == Qt::DisplayRole)
  42.             return QVariant(cnt.at(index.column()));
  43.         else
  44.             return QVariant();
  45.     }
  46.  
  47. protected:
  48.     void timerEvent(QTimerEvent *)
  49.     {
  50.         for(int i = 0; i < COL_CNT; ++i)
  51.             ++cnt[i];
  52.         emit dataChanged(index(0, 0), index(0, COL_CNT));
  53.     }
  54.  
  55. private:
  56.     QList<int> cnt;
  57. };
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when i connect this model to QTreeView
Qt Code: 
  1. int main(int argc, char *argv[])
  2. {
  3.     QApplication a(argc, argv);
  4.     CustomModel model;
  5.     QTreeView tree;
  6.     tree.setModel(&model);
  7.     tree.show();
  8.     return a.exec();
  9. }
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i get what i expected - 1 row, 7 columns and increasing counter in every column. then i add generic QSortFilterProxyModel:
Qt Code: 
  1. int main(int argc, char *argv[])
  2. {
  3.     QApplication a(argc, argv);
  4.     CustomModel model;
  6.     filter.setSourceModel(&model);
  7.     QTreeView tree;
  8.     tree.setModel(&filter);
  9.     tree.show();
  10.     return a.exec();
  11. }
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and i get following behaviour: in first column (column == 0) counter increases every second, just as planned. but in other columns counter freezes and updates only when i put mouse over, or resize header, or something else

i have resolved this issue in the following way
Qt Code: 
  1. void TransfersTreeSortFilterModel::mySetSourceModel(QAbstractItemModel *model)
  2. {
  3.     setSourceModel(model);
  4.     connect(model, SIGNAL(dataChanged(QModelIndex,QModelIndex)), this,
  5.             SLOT(sourceModelDataChanged(QModelIndex,QModelIndex)));
  6. }
  7.  
  8. void TransfersTreeSortFilterModel::sourceModelDataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight)
  9. {
  10.     emit dataChanged(mapFromSource(topLeft), mapFromSource(bottomRight));
  11. }
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but actually i'm not sure this is a good solution

can somebody explain, is this Qt bug or am i missing something?