Please review your example
https://www.dukascopy.com/wiki/en/devel ... ple-inputs
It does not work with price based charts.

The problem is the offer side and the instrument selection.

              new InputParameterInfo("ASK", InputParameterInfo.Type.BAR){{
                 setOfferSide(OfferSide.ASK);
                 setInstrument(Instrument.GBPUSD);
              }},

Once your remove the red indicated part, it works.
setOfferSide(OfferSide.ASK);
setInstrument(Instrument.GBPUSD);
It seems the JForex indicator engine does not allow any settings inside InputParameterInfo object, if applied on price based charts.

Please fix this.

Here comes a very simple example.
If you apply the indicator "VOLUMEBS" (see below) to a 10 Ticks Bar Chart, then it shows you volumes on Ask charts only. There is nothing on a Bid chart.
It seems that the

 setOfferSide(OfferSide.ASK);

forced JForex to void the indicator.

Indicator calculation on custom input data is implemented only for time aggregated data or ticks.

On charts with price aggregated data types sample indicator from Wiki must receive chart's PA bars as main input and different number of TA candles as other inputs.
Period of this candles is equal to base period of PA data (7 days) if it wasn't explicitly set for each input.

Could you give an example how to solve this or could you implement the missing part?

Please help as I don't know how to handle your answer.

Hello,

Unfortunately, for PA charts isn't possible implement this logic. For specified time interval, depending on selected OfferSide, input data have different amount of elements and bars between themselves will not be logically related. In this case, the correct visualization of indicator isn't seen as possible.