Cleanup QtWidgets examples

Cleanup QtWidgets examples:
 - use nullptr (clang-tidy)
 - use member-initialization
 - adjust the style
 - fix includes

Change-Id: Ic5448606aacc525ea60b615a69227017aa2b821a
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

1 files changed, 7 insertions, 2 deletions

diff --git a/examples/widgets/statemachine/eventtransitions/main.cpp b/examples/widgets/statemachine/eventtransitions/main.cpp
index 2de8e5daa3..fe9518092f 100644
--- a/examples/widgets/statemachine/eventtransitions/main.cpp
+++ b/examples/widgets/statemachine/eventtransitions/main.cpp
@@ -48,13 +48,18 @@
 **
 ****************************************************************************/
 
-#include <QtWidgets>
+#include <QApplication>
+#include <QEventTransition>
+#include <QPushButton>
+#include <QStateMachine>
+#include <QVBoxLayout>
+#include <QWidget>
 
 //! [0]
 class Window : public QWidget
 {
 public:
-    Window(QWidget *parent = 0)
+    Window(QWidget *parent = nullptr)
         : QWidget(parent)
     {
         QPushButton *button = new QPushButton(this);