1 files changed, 2 insertions, 1 deletions
diff --git a/examples/widgets/tools/echoplugin/echowindow/echointerface.h b/examples/widgets/tools/echoplugin/echowindow/echointerface.h
index 1915330e21..fb07f7fb79 100644
--- a/examples/widgets/tools/echoplugin/echowindow/echointerface.h
+++ b/examples/widgets/tools/echoplugin/echowindow/echointerface.h
@@ -51,13 +51,14 @@
 #ifndef ECHOINTERFACE_H
 #define ECHOINTERFACE_H
 
+#include <QObject>
 #include <QString>
 
 //! [0]
 class EchoInterface
 {
 public:
-    virtual ~EchoInterface() {}
+    virtual ~EchoInterface() = default;
     virtual QString echo(const QString &message) = 0;
 };