Camera example: Don't crash is the system doesn't have a camera

Don't assume the list of camera formats is non empty.

Change-Id: Id64772b8db165357d350456df9174a6659f7c8d8
Reviewed-by: André de la Rocha <andre.rocha@qt.io>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
(cherry picked from commit 315dff497c78526888121c7f84e0074208261129)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 10 insertions, 8 deletions

diff --git a/examples/multimediawidgets/camera/camera.cpp b/examples/multimediawidgets/camera/camera.cpp
index 3ddb78597..e87ef47f1 100644
--- a/examples/multimediawidgets/camera/camera.cpp
+++ b/examples/multimediawidgets/camera/camera.cpp
@@ -136,18 +136,20 @@ void Camera::setCamera(const QCameraDevice &cameraDevice)
         // Setting default settings.
         // The biggest resolution and the max framerate
         auto formats = cameraDevice.videoFormats();
-        auto defaultFormat = formats.first();
+        if (!formats.isEmpty()) {
+            auto defaultFormat = formats.first();
 
-        for (const auto &format : formats) {
+            for (const auto &format : formats) {
 
-            bool isFormatBigger = format.resolution().width() > defaultFormat.resolution().width()
-                    && format.resolution().height() > defaultFormat.resolution().height();
+                bool isFormatBigger = format.resolution().width() > defaultFormat.resolution().width()
+                        && format.resolution().height() > defaultFormat.resolution().height();
 
-            defaultFormat = isFormatBigger ? format : defaultFormat;
-        }
+                defaultFormat = isFormatBigger ? format : defaultFormat;
+            }
 
-        m_camera->setCameraFormat(defaultFormat);
-        m_mediaRecorder->setVideoFrameRate(defaultFormat.maxFrameRate());
+            m_camera->setCameraFormat(defaultFormat);
+            m_mediaRecorder->setVideoFrameRate(defaultFormat.maxFrameRate());
+        }
     }
 
     m_camera->start();