topic Re: 10.1 List in Value Table in Python Toolbox in Python Questions

10.1 List in Value Table in Python Toolbox

GeorgeRaber — Wed, 02 May 2012 02:35:14 GMT

I am trying to create a Python Toolbox in ArcGIS 10.1 and can't seem to replicate something like what I see in the Summary Statistics tool where the user builds a Value Table that contains a list of Fields and then within the table the user must pick from a list of valid Statistic types (SUM, MEAN, etc). Anyone have an idea or experience doing this? Thanks.

Re: 10.1 List in Value Table in Python Toolbox

DavidWynne — Sun, 12 Dec 2021 06:57:55 GMT

I am trying to create a Python Toolbox in ArcGIS 10.1 and can't seem to replicate something like what I see in the Summary Statistics tool where the user builds a Value Table that contains a list of Fields and then within the table the user must pick from a list of valid Statistic types (SUM, MEAN, etc). Anyone have an idea or experience doing this? Thanks.

Unfortunately, adding a drop-down of keywords is not supported at the moment in a Python toolbox value table parameter. The way it's implemented right now, the closest that can be done would be to validate the column in updateMessages and add messages to the parameter indicating the choices. Admittedly that's far from ideal.

If you want to create an exact match of the Summary Statistic tool's value table parameter that is a little easier. You could mine the parameter from the tool using the arcpy.GetParameterInfo function and use that in python toolbox tool's getParameterInfo. Something like this below:

    def getParameterInfo(self):
        in_table = arcpy.Parameter(
            name="in_table",
            displayName="Input Table",
            datatype="Table View",
            direction="Input",
            parameterType="Required")
        
        stats_field = arcpy.GetParameterInfo("Statistics_analysis")[2]
        stats_field.parameterDependencies = [in_table.name]

        return [in_table, stats_field]

-Dave

Re: 10.1 List in Value Table in Python Toolbox

NikolayVladimirovich — Wed, 26 Dec 2012 10:01:05 GMT

Hello, are there any progress in this matter? I interested in realization "Obtained from" for multiple values. Like in "Topo to raster" for feature and Z-field. Sorry for bad english.
- Nick

Re: 10.1 List in Value Table in Python Toolbox

MelanieMaguire — Wed, 26 Dec 2012 13:24:54 GMT

Thanks Dave. I will have to try that out. George, there is also a summary statistics tool in the statistics toolbox that you might be interested in. http://resources.arcgis.com/en/help/main/10.1/index.html#/Summary_Statistics/00080000001z000000/

Re: 10.1 List in Value Table in Python Toolbox

JamieKass — Fri, 01 Mar 2013 19:55:59 GMT

This is a good quick fix, but I would very much like the functionality available to replicate any tool GUI behavior in a python toolbox, especially the ability to have the user select values from a multivalue string list that gets returned as a list.

Re: 10.1 List in Value Table in Python Toolbox

NikolayVladimirovich — Tue, 12 Mar 2013 11:25:35 GMT

Still no answer?

Re: 10.1 List in Value Table in Python Toolbox

TimDonoyou — Fri, 27 Sep 2013 08:29:37 GMT

Hi All,

Appreciate this is an old thread but any progress on this? has it been solved in 10.2?

I have looked at the help menus but it doesn't give any more information than 10.1 version.

If possible I would like a 2 column input table - column 1 will be a habitat type selected from a dropdown and then column 2 would be a species selected from another dropdown whose values would change depending on the habitat selected for column 1.

Cheers

Tim

Re: 10.1 List in Value Table in Python Toolbox

RichardFairhurst — Fri, 27 Sep 2013 15:54:53 GMT

Here are two blogs on the subject. Generating a choice list from a field. and Generating a multivalue choice list.. I know there was another blog that laid the process out better that I used, but I have not been able to find it so far.

Generally interactive list dependencies are handled in the tool Validation script. I have done this in the past and created tools where user interaction with one component of a tool updated a choice list in another part of the tool. It worked OK when I did this for a two field dependency. You have to be pretty skilled at Python to make it work really well since once you understand the principles there are many subtle adjustments that can customize the list behaviors beyond what the blogs cover. Testing and modifying the tool is not well supported so I am not willing to instruct a Python novice on how to set it up and customize it through the forum. Get comfortable with Python before attempting this.

But the principles for modifying the tool validation do not scale well as you make your tool increasingly complex. When I got to about 7 field interactions on a single tool I needed over 700 lines of validation code to make the interactions work the way I wanted. The performance of the tool tanked to the point where it took 5 to 10 minutes just to load the tool for editing and it took minutes to run. At that point I abandoned the tool and ended up going to .Net Add-ins. .Net has no problem with very complex forms, gave me a lot more interface options and performs great. So for really involved user interfaces that go beyond simple two field interactions you should create add-ins with .Net that use Windows forms and UI components.

Re: 10.1 List in Value Table in Python Toolbox

TimDonoyou — Sat, 28 Sep 2013 21:04:33 GMT

Hi Richard

Many thanks for your advice and links - really helpful.

While I admit I am not a python expert I have created scripts to automate many of our workflows and have included validation scriptswith these so have more than a basic knowledge.

What I am hoping to achieve is a combination of using a featureset and recordset or attribute lists to add multiple species to a ecology habitat type...the user will click a point to add a habitat type which can be from a feature template or a list parameter...the habitat type selected will determine the species list dropdown - i can do this already using the vaildation script to change the species tick list...BUT...if possible I would really like to also include an abundance attribute (D, A, F, O, R) for each species and this is not possible at the moment as the value list defaults to a ticklist - do you know if it is possible to create a value table for string parameters?

or would I be better off going the .net route? if so where is the best place to get started?

Any pointers are much appreciated.

Cheers

Tim

Re: 10.1 List in Value Table in Python Toolbox

RichardFairhurst — Sat, 28 Sep 2013 22:57:55 GMT

Hi Richard

Many thanks for your advice and links - really helpful.

While I admit I am not a python expert I have created scripts to automate many of our workflows and have included validation scriptswith these so have more than a basic knowledge.

What I am hoping to achieve is a combination of using a featureset and recordset or attribute lists to add multiple species to a ecology habitat type...the user will click a point to add a habitat type which can be from a feature template or a list parameter...the habitat type selected will determine the species list dropdown - i can do this already using the vaildation script to change the species tick list...BUT...if possible I would really like to also include an abundance attribute (D, A, F, O, R) for each species and this is not possible at the moment as the value list defaults to a ticklist - do you know if it is possible to create a value table for string parameters?

or would I be better off going the .net route? if so where is the best place to get started?

Any pointers are much appreciated.

Cheers

Tim

I know that the validation for the second combobox drop down uses a cursor to get the value list. The drop down list can be modified at runtime with string values. I have a sample tool with two coordinated drop downs at work, but cannot access it at the moment. In any case, it should be possible using either the tool or .Net as long as you don't need to continue expanding the interface with a lot more runtime updates. As I said, .Net works much better for many controls that interact with your databases at runtime.

A value table of multiple columns does not work as far as I know in the tool. At the very least I never found any documentation that explained how to get the tool to emulate such things as the Sort tool table parameters. .Net can handle it with listbox or datagrid tools.

Re: 10.1 List in Value Table in Python Toolbox

Anonymous User — Sun, 12 Dec 2021 06:57:58 GMT

I know this is an old post, but I have been struggling with this as well and wanted to post a solution. I was able to figure out a very clunky workaround that does allow you to create your own drop down. In my case, I did not actually use a "Field" value for the first part of the drop down but rather a list of Land use values derived from an input table's field values.

By using suggestions from David Wynne above, I was able to "trick" the GP framework with a Python toolbox. I made a copy of the Summary Statistics parameter as suggested, then modified the parameter filter lists like this:

parameters[7].filters[1].list = ['some_list', ...]

And the relevant code:

# global var
CURVE_NUMS = [[u'Agricultural', 30.0, 58.0, 71.0, 80.0, 30.0], ...]# more values ommitted
    
    def getParameterInfo(self):
         fmap = arcpy.GetParameterInfo("Statistics_analysis")[2]
         
    def updateParameters(self, parameters):
        """Modify the values and properties of parameters before internal
        validation is performed.  This method is called whenever a parameter
        has been changed."""
        if parameters[4].value:
            if parameters[4].valueAsText != LULC_FIELD and not parameters[6].altered:
                setattr(sys.modules[__name__], LULC_FIELD, parameters[4].valueAsText)

                with arcpy.da.SearchCursor(parameters[3].valueAsText, [parameters[4].valueAsText]) as srows:
                    lulc_vals = sorted(list(set([str(r[0]) for r in srows]))) # get land use values from field

                parameters[6].values = CURVE_NUMS

                # create dummy table
                parameters[7].value = [[l, ' '] for l in lulc_vals]  #assign a default of " " so the user can fill in drop down
                parameters[7].filters[1].list = [r[0] for r in CURVE_NUMS]  # IMPORTANT, update the filter list from summary stats to your own list


        return

And the drop down:

This is not customizable, as you can only use the two columns and you cannot rename the parameter, but it does work. Hopefully Esri supports this behavior in the future.

It would be nice if you could set a list filter for multiple columns like this:

parameters.filter.list = [[list1,...], [list2]]

Re: 10.1 List in Value Table in Python Toolbox

JasonXue — Wed, 02 Nov 2016 18:35:39 GMT

Could you tell me how to make a parameter like this as I circled as below? I need to a parameter can be used to show a table content? Thanks.

Re: 10.1 List in Value Table in Python Toolbox

curtvprice — Sat, 26 Nov 2016 02:30:47 GMT

This supported at 10.3 and later.

Defining parameters in a Python toolbox—Help | ArcGIS for Desktop : Creating value table parameters