The next widget that is causing me a head-ache, the QListWidget. I never get to catch the key press event in a QListWidget. Reproduce:
moc test2.h -o test2_moc.cpp
g++ -g test2* -I /usr/local/TrollTech/Qt-4.1.0/include -L /usr/local/TrollTech/Qt-4.1.0/lib -lQtGui_debug -lQtCore_debug
test2.h
Qt Code: 
  1. #include <QtGui/QtGui>
  2.  
  3. class Test: public QObject
  4. {
  5.   Q_OBJECT
  6. public:
  7.   bool eventFilter(QObject *o, QEvent *e);
  8. };
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test2.cpp
Qt Code: 
  1. #include "test2.h"
  2.  
  3. void addit(QObject * o, Test * t)
  4. {
  5.   o->installEventFilter(t);
  6.   foreach (QObject * cobj, o->children())
  7.     addit(cobj, t);
  8. }
  9.  
  10. bool Test::eventFilter(QObject *o, QEvent *e)
  11. {
  12.   if (e->type() == QEvent::MouseButtonPress) {
  13.       qDebug() << "QEvent::MouseButtonPress:";
  14.       o->dumpObjectInfo();
  15.   } else if (e->type() == QEvent::MouseButtonRelease) {
  16.       qDebug() << "QEvent::MouseButtonRelease:";
  17.       o->dumpObjectInfo();
  18.   }   if (e->type() == QEvent::KeyPress) {
  19.       qDebug() << "QEvent::KeyPress:";
  20.       o->dumpObjectInfo();
  21.   } else if (e->type() == QEvent::KeyRelease) {
  22.       qDebug() << "QEvent::KeyRelease:";
  23.       o->dumpObjectInfo();
  24.   }
  25.   return false;
  26. }
  27.  
  28. int main(int argc, char * argv[])
  29. {
  30.   QApplication app(argc, argv);
  31.   QListWidget * list = new QListWidget();
  32.   Test * test = new Test();
  33.   addit(list, test);
  34.   QListWidgetItem * newItem = new QListWidgetItem("foo 1", list);
  35.   newItem->setFlags(Qt::ItemIsEditable);
  36.   list->show();
  37.   return app.exec();
  38. }
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Start and double click the 'foo 1' item to begin editing it. Type any key.
The strange thing is that the key releases are caught, but never the key presses.
I tried various things, like looking at the list->itemWidget(item), but that always returns 0 at the places I tried (like after the doubleclick). Where is the keypress handled?

Greetings,
Beluvius