Make examples return -1 on load failures.

Avoid hanging processes and empty windows in case some module is not
installed.

Change-Id: Ib220a6251076fd1fdbd126524a723d5c3f94bfb9
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@theqtcompany.com>

12 files changed, 24 insertions, 1 deletions

diff --git a/examples/quick/controls/basiclayouts/src/main.cpp b/examples/quick/controls/basiclayouts/src/main.cpp
index bb4b3bdd..e66387f7 100644
--- a/examples/quick/controls/basiclayouts/src/main.cpp
+++ b/examples/quick/controls/basiclayouts/src/main.cpp
@@ -45,5 +45,7 @@ int main(int argc, char *argv[])
 {
     QtQuickControlsApplication app(argc, argv);
     QQmlApplicationEngine engine(QUrl("qrc:/main.qml"));
+    if (engine.rootObjects().isEmpty())
+        return -1;
     return app.exec();
 }
diff --git a/examples/quick/controls/calendar/src/main.cpp b/examples/quick/controls/calendar/src/main.cpp
index 6b3c058a..bab7e4b2 100644
--- a/examples/quick/controls/calendar/src/main.cpp
+++ b/examples/quick/controls/calendar/src/main.cpp
@@ -48,5 +48,7 @@ int main(int argc, char *argv[])
     QtQuickControlsApplication app(argc, argv);
     qmlRegisterType<SqlEventModel>("org.qtproject.examples.calendar", 1, 0, "SqlEventModel");
     QQmlApplicationEngine engine(QUrl("qrc:/qml/main.qml"));
+    if (engine.rootObjects().isEmpty())
+        return -1;
     return app.exec();
 }
diff --git a/examples/quick/controls/filesystembrowser/main.cpp b/examples/quick/controls/filesystembrowser/main.cpp
index ac24bada..e9c63c20 100644
--- a/examples/quick/controls/filesystembrowser/main.cpp
+++ b/examples/quick/controls/filesystembrowser/main.cpp
@@ -143,6 +143,8 @@ int main(int argc, char *argv[])
     engine.rootContext()->setContextProperty("fileSystemModel", fsm);
     engine.rootContext()->setContextProperty("rootPathIndex", fsm->index(fsm->rootPath()));
     engine.load(QUrl(QStringLiteral("qrc:///main.qml")));
+    if (engine.rootObjects().isEmpty())
+        return -1;
 
     return app.exec();
 }
diff --git a/examples/quick/controls/gallery/main.cpp b/examples/quick/controls/gallery/main.cpp
index 4c254a4e..ac3f447d 100644
--- a/examples/quick/controls/gallery/main.cpp
+++ b/examples/quick/controls/gallery/main.cpp
@@ -52,5 +52,7 @@ int main(int argc, char *argv[])
         QSurfaceFormat::setDefaultFormat(fmt);
     }
     QQmlApplicationEngine engine(QUrl("qrc:/main.qml"));
+    if (engine.rootObjects().isEmpty())
+        return -1;
     return app.exec();
 }
diff --git a/examples/quick/controls/styles/main.cpp b/examples/quick/controls/styles/main.cpp
index 1f6684a6..55c592e6 100644
--- a/examples/quick/controls/styles/main.cpp
+++ b/examples/quick/controls/styles/main.cpp
@@ -47,6 +47,7 @@ int main(int argc, char *argv[])
 
     QQmlApplicationEngine engine;
     engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
-
+    if (engine.rootObjects().isEmpty())
+        return -1;
     return app.exec();
 }
diff --git a/examples/quick/controls/texteditor/src/main.cpp b/examples/quick/controls/texteditor/src/main.cpp
index 160e6a9a..1ef76e3a 100644
--- a/examples/quick/controls/texteditor/src/main.cpp
+++ b/examples/quick/controls/texteditor/src/main.cpp
@@ -47,5 +47,7 @@ int main(int argc, char *argv[])
     QtQuickControlsApplication app(argc, argv);
     qmlRegisterType<DocumentHandler>("org.qtproject.example", 1, 0, "DocumentHandler");
     QQmlApplicationEngine engine(QUrl("qrc:/qml/main.qml"));
+    if (engine.rootObjects().isEmpty())
+        return -1;
     return app.exec();
 }
diff --git a/examples/quick/controls/touch/src/main.cpp b/examples/quick/controls/touch/src/main.cpp
index bb4b3bdd..e66387f7 100644
--- a/examples/quick/controls/touch/src/main.cpp
+++ b/examples/quick/controls/touch/src/main.cpp
@@ -45,5 +45,7 @@ int main(int argc, char *argv[])
 {
     QtQuickControlsApplication app(argc, argv);
     QQmlApplicationEngine engine(QUrl("qrc:/main.qml"));
+    if (engine.rootObjects().isEmpty())
+        return -1;
     return app.exec();
 }
diff --git a/examples/quick/controls/uiforms/main.cpp b/examples/quick/controls/uiforms/main.cpp
index de92dd70..6a15842a 100644
--- a/examples/quick/controls/uiforms/main.cpp
+++ b/examples/quick/controls/uiforms/main.cpp
@@ -55,5 +55,7 @@ int main(int argc, char *argv[])
     qmlRegisterSingletonType(QUrl(QStringLiteral("qrc:/qml/CustomerModel.qml")), "io.qt.example", 1, 0, "CustomerModel");
 
     QQmlApplicationEngine engine(QUrl("qrc:/main.qml"));
+    if (engine.rootObjects().isEmpty())
+        return -1;
     return app.exec();
 }
diff --git a/examples/quick/dialogs/systemdialogs/main.cpp b/examples/quick/dialogs/systemdialogs/main.cpp
index f83c8c22..5f65ce04 100644
--- a/examples/quick/dialogs/systemdialogs/main.cpp
+++ b/examples/quick/dialogs/systemdialogs/main.cpp
@@ -53,5 +53,7 @@ int main(int argc, char *argv[])
         QSurfaceFormat::setDefaultFormat(fmt);
     }
     QQmlApplicationEngine engine(QUrl("qrc:/dialogs/systemdialogs/systemdialogs.qml"));
+    if (engine.rootObjects().isEmpty())
+        return -1;
     return app.exec();
 }
diff --git a/examples/quick/extras/dashboard/main.cpp b/examples/quick/extras/dashboard/main.cpp
index 77a0ada5..74ea0772 100644
--- a/examples/quick/extras/dashboard/main.cpp
+++ b/examples/quick/extras/dashboard/main.cpp
@@ -51,5 +51,7 @@ int main(int argc, char *argv[])
     app.setFont(QFont("DejaVu Sans"));
 
     QQmlApplicationEngine engine(QUrl("qrc:/qml/dashboard.qml"));
+    if (engine.rootObjects().isEmpty())
+        return -1;
     return app.exec();
 }
diff --git a/examples/quick/extras/flat/main.cpp b/examples/quick/extras/flat/main.cpp
index 1012fa4e..8faafdca 100644
--- a/examples/quick/extras/flat/main.cpp
+++ b/examples/quick/extras/flat/main.cpp
@@ -51,5 +51,7 @@ int main(int argc, char *argv[])
     }
     QQmlApplicationEngine engine;
     engine.load(QUrl("qrc:/main.qml"));
+    if (engine.rootObjects().isEmpty())
+        return -1;
     return app.exec();
 }
diff --git a/examples/quick/extras/gallery/main.cpp b/examples/quick/extras/gallery/main.cpp
index 9ba1835e..1d5d2313 100644
--- a/examples/quick/extras/gallery/main.cpp
+++ b/examples/quick/extras/gallery/main.cpp
@@ -45,5 +45,7 @@ int main(int argc, char *argv[])
 {
     QGuiApplication app(argc, argv);
     QQmlApplicationEngine engine(QUrl("qrc:/qml/gallery.qml"));
+    if (engine.rootObjects().isEmpty())
+        return -1;
     return app.exec();
 }