diff --git a/examples/video/qmlvideo/qmlapplicationviewer/qmlapplicationviewer.h b/examples/video/qmlvideo/qmlapplicationviewer/qmlapplicationviewer.h
index 9d8bd321..9abde2d2 100644
--- a/examples/video/qmlvideo/qmlapplicationviewer/qmlapplicationviewer.h
+++ b/examples/video/qmlvideo/qmlapplicationviewer/qmlapplicationviewer.h
@@ -43,8 +43,7 @@
 #define QMLAPPLICATIONVIEWER_H
 
 #include <QtQuick/QQuickView>
-
-class QGuiApplication;
+#include <QtGui/QGuiApplication>
 
 class QmlApplicationViewer : public QQuickView
 {
diff --git a/examples/video/qmlvideofx/qmlapplicationviewer/qmlapplicationviewer.h b/examples/video/qmlvideofx/qmlapplicationviewer/qmlapplicationviewer.h
index 9d8bd321..9abde2d2 100644
--- a/examples/video/qmlvideofx/qmlapplicationviewer/qmlapplicationviewer.h
+++ b/examples/video/qmlvideofx/qmlapplicationviewer/qmlapplicationviewer.h
@@ -43,8 +43,7 @@
 #define QMLAPPLICATIONVIEWER_H
 
 #include <QtQuick/QQuickView>
-
-class QGuiApplication;
+#include <QtGui/QGuiApplication>
 
 class QmlApplicationViewer : public QQuickView
 {
diff --git a/examples/video/snippets/frequencymonitor/frequencymonitor.h b/examples/video/snippets/frequencymonitor/frequencymonitor.h
index a949e55d..454633a6 100644
--- a/examples/video/snippets/frequencymonitor/frequencymonitor.h
+++ b/examples/video/snippets/frequencymonitor/frequencymonitor.h
@@ -43,8 +43,7 @@
 #define FREQUENCYMONITOR_H
 
 #include <QtCore/QObject>
-
-class QTimer;
+#include <QtCore/QTimer>
 
 class FrequencyMonitorPrivate;
 
diff --git a/examples/video/snippets/performancemonitor/performancemonitor.cpp b/examples/video/snippets/performancemonitor/performancemonitor.cpp
index 73ebe291..41a2d34b 100644
--- a/examples/video/snippets/performancemonitor/performancemonitor.cpp
+++ b/examples/video/snippets/performancemonitor/performancemonitor.cpp
@@ -40,7 +40,6 @@
 ****************************************************************************/
 
 #include "performancemonitor.h"
-#include <QtCore/QString>
 
 namespace PerformanceMonitor {
 
diff --git a/examples/video/snippets/performancemonitor/performancemonitor.h b/examples/video/snippets/performancemonitor/performancemonitor.h
index 59e90550..785f6338 100644
--- a/examples/video/snippets/performancemonitor/performancemonitor.h
+++ b/examples/video/snippets/performancemonitor/performancemonitor.h
@@ -42,7 +42,7 @@
 #ifndef PERFORMANCEMONITOR_H
 #define PERFORMANCEMONITOR_H
 
-class QString;
+#include <QtCore/QString>
 
 namespace PerformanceMonitor {
     struct State {