Polish the videowidget example.

- Add command line parsing and file argument.
- Port to Qt 5 connection syntax.
- Adapt size to available geometry (for High DPI).

Task-number: QTBUG-53114
Change-Id: I1c1c547ddb14210ef5900f99f4870d6d91b67088
Reviewed-by: Yoann Lopes <yoann.lopes@qt.io>

examples/multimediawidgets/videowidget/main.cpp

@@ -41,13 +41,36 @@
 #include "videoplayer.h"
 
 #include <QtWidgets/QApplication>
+#include <QtWidgets/QDesktopWidget>
+#include <QtCore/QCommandLineParser>
+#include <QtCore/QCommandLineOption>
+#include <QtCore/QDir>
 
 int main(int argc, char *argv[])
 {
     QApplication app(argc, argv);
 
+    QCoreApplication::setApplicationName("Video Widget Example");
+    QCoreApplication::setOrganizationName("QtProject");
+    QGuiApplication::setApplicationDisplayName(QCoreApplication::applicationName());
+    QCoreApplication::setApplicationVersion(QT_VERSION_STR);
+    QCommandLineParser parser;
+    parser.setApplicationDescription("Qt Video Widget Example");
+    parser.addHelpOption();
+    parser.addVersionOption();
+    parser.addPositionalArgument("url", "The URL to open.");
+    parser.process(app);
+
     VideoPlayer player;
-    player.resize(320, 240);
+    if (!parser.positionalArguments().isEmpty()) {
+        const QUrl url =
+            QUrl::fromUserInput(parser.positionalArguments().constFirst(),
+                                QDir::currentPath(), QUrl::AssumeLocalFile);
+        player.setUrl(url);
+    }
+
+    const QRect availableGeometry = QApplication::desktop()->availableGeometry(&player);
+    player.resize(availableGeometry.width() / 6, availableGeometry.height() / 4);
     player.show();
 
     return app.exec();