Override graphics settings in DirectShape objects

[Anonymous]

Hi Guys, 

I am overriding the graphics settings for each of my DirectShape objects I seem to be able to only control the color of the lines, but I can't get access to actually changing the color of the surfaces which I also need, only their transparency. 

The only way I could do it is  via the Revit UI  is there any way I can change the forground pattern to solid via the API?

here is my code:

´´´
 for (int i = 0; i < solids.Count; i++)
            {
               
                DirectShape ds = DirectShape.CreateElement(doc, category);
                ds.ApplicationId = id_addin;
                ds.ApplicationDataId = areaObjects[i].UniqueId;
                IList<GeometryObject> list = new List<GeometryObject>();
                GeometryObject g = solids[i] as GeometryObject;
                list.Add(g);
            
                ds.SetShape(list);

                Color color = new Color(255, 0, 0); 
                OverrideGraphicSettings overrideGS = new OverrideGraphicSettings();

                overrideGS.SetProjectionLineColor(color);
           
                overrideGS.SetSurfaceForegroundPatternColor(color);
                      
                overrideGS.SetSurfaceBackgroundPatternColor(color);
             
                overrideGS.SetSurfaceForegroundPatternVisible(true);

                overrideGS.SetSurfaceTransparency(35);

                overrideGS.SetCutLineColor(color);

                doc.ActiveView.SetElementOverrides(ds.Id, overrideGS);

                ds.Name = "Area volume for " + areaObjects[i].Name;

            }

´´´

Any hints would be great,

Thanks in advance

[jeremytammik]

The best way to control the direct shape graphic settings is probably via its category, cf. 

https://thebuildingcoder.typepad.com/blog/2018/01/directshape-topics-and-happy-new-year.html#7

[Anonymous]

@jeremytammik  thanks again for getting back! 

When I create my Direct Shape geometry as a  Generic Mass Category, under its properties palette it does not have a Material and Finishes Parameter,  the option to click Edit Type is grayed out  and even  the Edit In-Place button does not appear under the Modify | Generic Models ribbon. In Addition, what I do get instead is some sort of default structural property and a Rebar button replacing the Edit In-Place button. 

In contrast I modeled by hand a simple extrusion in Revit and I put it under the the Generic Mass Category as well. This element does have all the missing parts that my direct shape lacks

So if I try to access the Direct Shapes Material Parameter via   

var p =  ds.get_Parameter(BuiltInParameter.MATERIAL_ID_PARAM);

p in this case will always be null because the material parameter does not exist.

so doing

Set(material.Id);

will not be possible.

Another method I tried was to create a Shared Parameter file. The first step works, in the sense that I do get a Material parameter in the properties pallete. But it does not fully work because I cant Edit In-Place my Direct Shape to succesfully make  a change in its Material.

Do you have any idea what could be wrong?

Thanks again for your time