Catching an ESC press when editing a QTableWidgetItem

Question

How can I catch if the user edits a QTableWidgetItem and aborts it via pressing ESC? I process the content of the respective item by catching QTableWidget::cellDoubleClicked, and I know when something has been changed by listening to QTableWidget::cellChanged. But when the user presses ESC, I don't know it.

I tried to install an event filter on the QTableWidget, but it only catches key presses that the widget itself receives – the editor seems to be another thing.

Any help would be greatly appreciated!

Answer 1

You must use a delegate and use your eventFilter, the following code is an example:

#include <QApplication>
#include <QKeyEvent>
#include <QStyledItemDelegate>
#include <QTableWidget>

#include <QDebug>

class TableWidgetDelegate: public QStyledItemDelegate{
public:
    using QStyledItemDelegate::QStyledItemDelegate;
protected:
    bool eventFilter(QObject * object, QEvent * event){
        QWidget *editor = qobject_cast<QWidget*>(object);
        if(editor && event->type() == QEvent::KeyPress) {
            if(static_cast<QKeyEvent *>(event)->key() == Qt::Key_Escape){
                qDebug()<<"escape";
            }
        }
        return QStyledItemDelegate::eventFilter(editor, event);
    }
};

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QTableWidget w(6, 4);
    w.setItemDelegate(new TableWidgetDelegate);
    w.show();

    return a.exec();
}