[GIS] Defining Feature Set parameter for ArcGIS Python Toolbox tool

arcpypython-toolbox

I'm trying to create an ArcGIS Python Toolbox tool which uses a polygon for input.

I want the user to be able to create the polygon when the tool is run.

I know how to do this using both a ModelBuilder model A quick tour of using Feature Set and Record Set and for a Python Script tool in a normal toolbox. This is done using a Feature Set variable by setting the schema to a polygon feature class.

I know from here Defining parameter data types in a Python toolbox that the datatype for Feature Set in a python toolbox is GPFeatureRecordSetLayer.

If I define the parameter as below it is not possible to create a polygon at run time. I’m almost 100% sure that this is because I have not set a schema. But does anybody know how to set the schema or know if there is some other way to interactively create a polygon and use as input for a Python Toolbox tool?

InteractiveParameter = arcpy.Parameter(
displayName="Interactive polygon",
name="toolname",
datatype="GPFeatureRecordSetLayer",
parameterType="Required",
direction="Input",
enabled = True)

Best Answer

The code example below is from the ArcGIS 10.1 Help page called Defining parameters in a Python toolbox which you have mentioned in your Question.

I think the step you have overlooked is the last one where you need to specify a polygon feature class or layer file (*.lyr). The example code references a layer file called Fire_Station.lyr.

def getParameterInfo(self):
    param0 = arcpy.Parameter(
        displayName="Input Feature Set",
        name="in_feature_set",
        datatype="GPFeatureRecordSetLayer",
        parameterType="Required",
        direction="Input")

    # Use __file__ attribute to find the .lyr file (assuming the
    #  .pyt and .lyr files exist in the same folder)
    param0.value = os.path.join(os.path.dirname(__file__),
                                "Fire_Station.lyr")

Related Solutions

ArcPy – Can One Parameter Choice in Python Toolbox Set Display Names of Other Parameters?

You know, anything is probably possible but that doesn't mean it is worth the effort. UpdateParameters is meant to update parameter values dynamically. Not parameter display names.

If I were trying to do this, I would create a Python Toolbox with two tools in it, ToolA for Category A and ToolB for Category B, each tool having the appropriate DisplayNames for its parameters.

To make the tool selection pretty simple for a user, I would then create a Python Add-in with two buttons (Category A and Category B). Then save the Python Toolbox into the Install Folder of your Python Add-in. When the user clicks the Category A button, launch ToolA from the Python Toolbox, when they click the Category B button on the Python Add-In, launch the ToolB from the Python Toolbox.

You can accomplish this using the pythonaddins.GPToolDialog function like so:

import os  
import arcpy  
import pythonaddins  
relPath = os.path.dirname(__file__)

class CAT_A(object):  
    """Implementation for Project_addin.CategoryA (Button)"""  
    def __init__(self):  
        self.enabled = True  
        self.checked = False  
    def onClick(self):  
        PythonTBX = relPath + r"\YourToolBox.pyt"  
        pythonaddins.GPToolDialog(PythonTBX, "ToolA")

class CAT_B(object):  
    """Implementation for Project_addin.CategoryB (Button)"""  
    def __init__(self):  
        self.enabled = True  
        self.checked = False  
    def onClick(self):  
        PythonTBX = relPath + r"\YourToolBox.pyt"  
        pythonaddins.GPToolDialog(PythonTBX, "ToolB")

There's a couple of advantages to this approach.

Stupid simple deployment of the Toolbox through a Python Add-in
A user can then access the tools through a simple button on a toolbar rather than through a series of nested menus in a toolbox in their Catalog Window and doesn't have to create a Catalog Connection to the location where the toolbox is hosted on their system.
An end user who wanted to alter the source code of the toolbox or tools is going to need to step up their game a little bit as they'll need to figure out that to get to the source code of the toolbox, they have to find the assembly cache where the addin is loaded. It's not obvious where this is located and the end user will not see this toolbox in their my toolboxes in catalog. The only way to access it will be through the Add-in unless they create a Catalog Connection to the assembly cache.
You can restrict the Addin Manager to only install Trusted (Signed) Addins, then Sign the addin with your signing certificate. If anyone does manage to locate and modify the source code, the signature will become invalid and the Addin will uninstall automagically.

ArcGIS Python Toolbox – Using Two Input Feature Layers and Derived Output Feature Layer

The output parameter, when I've used it, seems to really only work to add the output as a layer to the map document the tool has been called in.

I noticed something that may be giving you errors in your code:

if parameters[0].altered:
     parameters[1].value = arcpy.ValidateFieldName(parameters[1].value, parameters[0].value)

parameter[1] is equivalent to in_alignment which is a feature layer. The ValidateFieldName tool requires the name of a field as a string. The tool is meant to check that a string can be used as a field name in a particular feature class.

Also, the steps you are currently doing the execute, is you are updating the input point feature class with all the attributes. This presumes that the list of fields are in the point feature class.

Best Answer

Related Solutions

ArcPy – Can One Parameter Choice in Python Toolbox Set Display Names of Other Parameters?

ArcGIS Python Toolbox – Using Two Input Feature Layers and Derived Output Feature Layer

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