void CameraApp::MainPage::InitCaptureSettings()
{
log.OutputLog(L"MainPage::InitCaptureSettings");
m_CaptureInitSettings = ref new MediaCaptureInitializationSettings();
m_CaptureInitSettings->AudioDeviceId = "";
m_CaptureInitSettings->VideoDeviceId = "";
m_CaptureInitSettings->StreamingCaptureMode = StreamingCaptureMode::AudioAndVideo;
m_CaptureInitSettings->PhotoCaptureSource = PhotoCaptureSource::VideoPreview;

if(m_DeviceVector.size() > 0)
    m_CaptureInitSettings->VideoDeviceId = m_DeviceVector[0]->Id;
}

void CameraApp::MainPage::InitMediaCapture()
{
log.OutputLog(L"MainPage::InitMediaCapture");


auto _this = this;
m_MediaCaptureMgr = ref new MediaCapture();

task<void> stratPreview(m_MediaCaptureMgr->InitializeAsync(m_CaptureInitSettings)); ///   fails here
 stratPreview.then([_this]
 {
  _this->log.OutputLog(L"MainPage::InitializeAsync");
   _this->previewElement->Source = _this->m_MediaCaptureMgr;
  task<void> startPrev(_this->m_MediaCaptureMgr->StartPreviewAsync());
    startPrev.then([=]
    {
     _this->log.OutputLog(L"MainPage::StartPreviewAsync");
      return _this->GetCameraSettings();
     });
 });
}