#include <QtGui>

class MyTreeView : public QTreeView
{
public:
    MyTreeView(QWidget *parent = 0) : QTreeView(parent)
    {}
protected:
    bool edit(const QModelIndex &index, EditTrigger trigger, QEvent *event)
    {
        if (trigger == QAbstractItemView::SelectedClicked && index == previousEditIndex) {
            previousEditIndex = QModelIndex();
            return false;
        } else if (trigger != QAbstractItemView::NoEditTriggers)
            previousEditIndex = index;
        else if (trigger == QAbstractItemView::NoEditTriggers 
                && event->type() != QEvent::MouseButtonPress)
            previousEditIndex = QModelIndex();
        return QTreeView::edit(index, trigger, event);
    }
private:
    QPersistentModelIndex previousEditIndex;
};