Migrating dynamicwhere from android to ios on oxygene

Sorry to ask here but im lossing my hair and cant undesrtand how predicates work.

needs to migrate thats simple code in android

var awTipoActividad: WhereExpression := new BinaryExpression(new FieldExpression(fld_tipoactividad_idempresa), new ConstantExpression(adapter_tablecompanyid, DataType.String), BinaryOperator.Equal);
var listener: UIInteractionListener := OnUIInteraction;
  DataAdapter.fillAsync(temp, tempWhere, new class FillRequestTask.Callback (completed := method (aTask: FillRequestTask; aState: Object)
  //DataAdapter.fillAsync(self.data.fTipoActividad, awTipoActividad, new class FillRequestTask.Callback (completed := method (aTask: FillRequestTask; aState: Object)
  begin
    if aTask.isFailed() or aTask.isCancelled() then
    begin
      if assigned(listener) then
      begin
        listener.showMessage(aTask.getFailureCause().getMessage());
        //listener.alertError(aTask.getFailureCause().getMessage());
      end;
    end
    else
    begin
      if assigned(listener) then
      begin
        listener.notifyDataSetChanged();
        // agrego tablas.
        aBriefcase.addTable(self.data.fTipoActividad);
        aBriefcase.addTable(self.data.fLocaciones);
        aBriefcase.addTable(self.data.fBitacoraEntidad);
        {$IFDEF EXTREME_DEBUG}
        listener.showMessage('TipoActividad recordcount '+remobjects.elements.rtl.Convert.ToString(self.data.TipoActividadView.Count));
        {$ENDIF}
        // grabo tablas con datos
        aBriefcase.writeBriefcase();
        listener.showMessage('Datos sincronizados');
      end;
    end;
    aTask.get();
  end)).execute();