Cleanup QtWidgets (tools) examples

Cleanup QtWidgets tools examples:
 - use member-init (clang-tidy)
 - fix includes/don't include QtWidgets globally
 - include own header first
 - use nullptr (clang-tidy)
 - avoid c-style casts
 - use QVector instead QList
 - use QItemDelegate instead QStyledItemDelegate

Change-Id: Ibe9440cdf711e5cc2138c054864edebe1fc95731
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

1 files changed, 11 insertions, 3 deletions

diff --git a/examples/widgets/tools/echoplugin/echowindow/echowindow.cpp b/examples/widgets/tools/echoplugin/echowindow/echowindow.cpp
index 6886a4cd88..dce6bdedc3 100644
--- a/examples/widgets/tools/echoplugin/echowindow/echowindow.cpp
+++ b/examples/widgets/tools/echoplugin/echowindow/echowindow.cpp
@@ -48,10 +48,17 @@
 **
 ****************************************************************************/
 
-#include <QtWidgets>
-
 #include "echowindow.h"
 
+#include <QCoreApplication>
+#include <QDir>
+#include <QLabel>
+#include <QLayout>
+#include <QLineEdit>
+#include <QMessageBox>
+#include <QPluginLoader>
+#include <QPushButton>
+
 //! [0]
 EchoWindow::EchoWindow()
 {
@@ -101,7 +108,7 @@ void EchoWindow::createGUI()
 //! [3]
 bool EchoWindow::loadPlugin()
 {
-    QDir pluginsDir(qApp->applicationDirPath());
+    QDir pluginsDir(QCoreApplication::applicationDirPath());
 #if defined(Q_OS_WIN)
     if (pluginsDir.dirName().toLower() == "debug" || pluginsDir.dirName().toLower() == "release")
         pluginsDir.cdUp();
@@ -121,6 +128,7 @@ bool EchoWindow::loadPlugin()
             echoInterface = qobject_cast<EchoInterface *>(plugin);
             if (echoInterface)
                 return true;
+            pluginLoader.unload();
         }
     }