gui: Add GUIUtil::ItemDelegate with keyEscapePressed signal

src/qt/guiutil.cpp

@@ -49,6 +49,7 @@
 #include <QDoubleValidator>
 #include <QFileDialog>
 #include <QFont>
+#include <QKeyEvent>
 #include <QLineEdit>
 #include <QSettings>
 #include <QTextDocument> // for Qt::mightBeRichText
@@ -927,4 +928,14 @@ void ClickableProgressBar::mouseReleaseEvent(QMouseEvent *event)
     Q_EMIT clicked(event->pos());
 }
 
+bool ItemDelegate::eventFilter(QObject *object, QEvent *event)
+{
+    if (event->type() == QEvent::KeyPress) {
+        if (static_cast<QKeyEvent*>(event)->key() == Qt::Key_Escape) {
+            Q_EMIT keyEscapePressed();
+        }
+    }
+    return QItemDelegate::eventFilter(object, event);
+}
+
 } // namespace GUIUtil

src/qt/guiutil.h

@@ -10,6 +10,7 @@
 
 #include <QEvent>
 #include <QHeaderView>
+#include <QItemDelegate>
 #include <QMessageBox>
 #include <QObject>
 #include <QProgressBar>
@@ -232,6 +233,18 @@ namespace GUIUtil
 
     typedef ClickableProgressBar ProgressBar;
 
+    class ItemDelegate : public QItemDelegate
+    {
+        Q_OBJECT
+    public:
+        ItemDelegate(QObject* parent) : QItemDelegate(parent) {}
+
+    Q_SIGNALS:
+        void keyEscapePressed();
+
+    private:
+        bool eventFilter(QObject *object, QEvent *event);
+    };
 } // namespace GUIUtil
 
 #endif // BITCOIN_QT_GUIUTIL_H