UDF flashing again

Jul 10, 2014 at 4:13 PM
Edited Jul 10, 2014 at 4:14 PM
My AddIn is built with .NET 4.5.1, ExcelDNA0.32, NetOffice
I have the following UDF, the flashing issue seemed fixed after I removed "IsMacroType=true" & "AllowReference=true"

But now the flashing issue comes back again! http://screencast.com/t/0MaR65Nr
Note the flash does not occur every time but very frequently and I am not sure when will it flash and when will not. thanks

[ExcelFunction(Description = "Returns a datapoint for the given symbol and column based on the given date/time.")]
public static object MyUDF(string symbol, string column, object onDate, string fillOpt, string frequency)
{
    string key =  symbol + column + onDate + fillOpt + frequency + "_datapoint";
    return ExcelAsyncUtil.Run("MyUDF", new object[] {symbol, column, onDate, fillOpt, frequency},
           delegate
           {


                        object datapoint;  //if the value exists in cache, return it, otherwise will call web service
                        if (CachedDataPoints.ContainsKey(key))
                        {
                            datapoint = CachedDataPoints[key];
                        }
                        else
                        {
                            datapoint = Container.Resolve<IMyWebService>().GetDataPointSync(symbol, column, onDate, fillOpt, frequency);
                            if (String.IsNullOrEmpty(datapoint.ToString())) datapoint = "NA";
                            //put value in cache so next time we can get it directly from cache instead of calling web service                                    
                             CachedDataPoints.Add(key, datapoint);
                        }
                        return datapoint;
           });
}