private ObservableCollection <QrCodeInfo> ReadQrCodeData()
{
ObservableCollection <QrCodeInfo> data = null;
try
{
using (var stream = m_Drawing.TryOpenStream(STREAM_NAME, AccessType_e.Read))
{
if (stream != null)
{
m_Logger.Log("Reading QR code data", LoggerMessageSeverity_e.Debug);
using (var reader = new StreamReader(stream))
{
data = m_Serializer.ReadSettings <ObservableCollection <QrCodeInfo> >(
reader, new PictureValueSerializer(m_Logger, m_Drawing));
}
}
}
}
catch (Exception ex)
{
m_Logger.Log(ex);
}
if (data != null)
{
var usedPictures = new List <IXObject>();
for (int i = data.Count - 1; i >= 0; i--)
{
if (data[i].Picture == null)
{
data.RemoveAt(i);
m_Logger.Log($"Removed dangling QR code data at index {i}", LoggerMessageSeverity_e.Debug);
}
//As we serialize names of the features (removing and readding QR code may cause duplication in the data which is not recognized as dangling)
else if (usedPictures.Find(p => p.Equals(data[i].Picture)) != null)
{
data.RemoveAt(i);
m_Logger.Log($"Removed duplicate QR code data at index {i}", LoggerMessageSeverity_e.Debug);
}
else
{
usedPictures.Add(data[i].Picture);
}
}
}
else
{
data = new ObservableCollection <QrCodeInfo>();
}
data.CollectionChanged += OnDataCollectionChanged;
Init(data);
return(data);
}
