Hi,

In a tree view I would like a QLineEdit where I can change the value with the mouse wheel.
The following idea works fine when I slowly scroll the wheel. But when I faster scroll the wheel sometimes I am missing a call to setModelData. This function is then only called when I click somewhere else in the tree view.

Thank you!

Qt Code: 
  1. QLineMouseEdit::QLineMouseEdit(QWidget *aParent): QLineEdit(aParent) {
  2.       setFocusPolicy(Qt::WheelFocus);
  3.    }
  4.  
  5.    void QLineMouseEdit::wheelEvent(QWheelEvent *aEvent) {
  6.          double LinearChange = 1;
  7.          if (LinearChange!=0) {
  8.             double Delta = aEvent->delta();
  9.             double OldValue = text().toDouble();
  10.             double NewValue = OldValue + Delta/120*LinearChange;
  11.             setText(QString::number(NewValue));
  12.             qDebug() << "";
  13.             qDebug() << "wheelEvent emit changed" << NewValue;  // ok!!
  14.             emit changed();
  15.             return;
  16.          }
  17.       }
  18.  
  19.    QWidget *CModelTreeDelegate::createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const {
  20. 	  QLineMouseEdit *Editor = new QLineMouseEdit(parent);
  21. 	  connect(Editor, SIGNAL(changed()), this, SLOT(changed()));
  22. 	  return Editor;
  23.    }
  24.  
  25.    void CModelTreeDelegate::setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const {
  26.       qDebug() << "CModelTreeDelegate::setModelData"; // ??? sometimes too late ???
  27.       QItemDelegate::setModelData(editor, model, index);
  28.    }
  29.  
  30.    void CModelTreeDelegate::changed() {
  31.       QLineMouseEdit *Editor = qobject_cast<QLineMouseEdit *>(sender());
  32.       if (Editor) {
  33.          qDebug() << "CComboDelegate::changed emit commitData"; // ok!!
  34.          emit commitData(Editor);
  35.       }
  36.     }
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