diff --git a/src/highlightanimation.h b/src/highlightanimation.h
index 178ca826..e7178256 100644
--- a/src/highlightanimation.h
+++ b/src/highlightanimation.h
@@ -24,7 +24,7 @@ class HighlightAnimation : public QObject, public QGraphicsLineItem
     Q_OBJECT
     Q_PROPERTY(qreal opacity READ opacity WRITE setOpacity)
 public:
-    HighlightAnimation(const QLineF &line);
+    explicit HighlightAnimation(const QLineF &line);
 };
 
 #endif // HIGHLIGHTANIMATION_H
diff --git a/src/themegraphicsitems.h b/src/themegraphicsitems.h
index 44dd1dc3..c1e1516e 100644
--- a/src/themegraphicsitems.h
+++ b/src/themegraphicsitems.h
@@ -21,7 +21,7 @@
 class KSquaresSquareItem : public QGraphicsRectItem
 {
 public:
-    KSquaresSquareItem(QGraphicsItem *parent = 0);
+    explicit KSquaresSquareItem(QGraphicsItem *parent = 0);
     ~KSquaresSquareItem();
 
     void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = 0);