Model Builder Parameters: Restrict input layer choice to a subset of layers

MWing

I have a model that requires a user to select one of several rasters as a model parameter (input variable). By default, all the rasters in the TOC are available as parameter choices and are accessible in the dialog box for the model through a drop down button. I'd like some of these raster layers to not be available to the model user. How could I restrict the available layer list to a subset?

    Thank you,
    Michael

DarrenWiens2

I'm not sure how you can achieve this in Model Builder, but once you're model is completely finished, you can export it to a Python script, create a script tool, and use validation to customize the filter.

  def initializeParameters(self):
    """Refine the properties of a tool's parameters.  This method is
    called when the tool is opened."""
    mxd = arcpy.mapping.MapDocument("CURRENT")
    lyrs = arcpy.mapping.ListLayers(mxd)
    compare_list = ['points','buff','something_else'] # the full list of layers you want to consider
    param_list = []
    for lyr in lyrs:
        if lyr.name in compare_list:
            param_list.append(lyr.name) # add to internal list
    self.params[2].filter.list = param_list # overwrite filter list
    return