Desktop Flow Custom Actions (preview) ActionSelector Problem

[quer13]

Hi all,

I test and develop custom actions for Power Automate Deskop Flows.

I read the documentation, but in the sample file "CentralCustomAction.cs" I ask me for using the selector with friendly text inside of combobox and not just numbers.

In sample code we have this definition of enum:

I modified it to:

To use the nice enum description for the selector list text, I added the code as shown in the red box.

But the result of the action in Power Automate is this:

I still have the numbers as selection list text and not my description text from the enumeration.

Where is my mistake or is it just a bug in preview?

Regards,

Markus

[quer13]

Is there no one who tries to create a new Custom Action (Preview) in PAD with use of selectors?

[eJackson]

I've been having the exact same issue. The documentation doesn't do a great job in my opinion, and I've been unable to find anything about it online. 

There's only ~500 people that have even downloaded the SDK for use, so I'm not super hopeful for the future of custom actions.

[kinuasa]

How about changing the "Selector" type?

using System.ComponentModel;
using Microsoft.PowerPlatform.PowerAutomate.Desktop.Actions.SDK.Attributes;
using Microsoft.PowerPlatform.PowerAutomate.Desktop.Actions.SDK;

namespace Modules.CustomModule
{
    [Action(Id = "Action1")]
    public class Action1 : ActionBase
    {
        public enum SelectorChoice
        {
            [Description("one")]
            Selector1,
            [Description("two")]
            Selector2,
            [Description("three")]
            Selector3
        }

        [InputArgument(typeof(SelectorChoice), true, false), DefaultValue("two")]
        public string Selector { get; set; }

        [InputArgument(Order = 1)]
        public string FirstName { get; set; }

        [InputArgument(Order = 2)]
        public string LastName { get; set; }

        [InputArgument(Order = 3)]
        public int Age { get; set; }

        [OutputArgument]
        public string DisplayedMessage { get; set; }

        public override void Execute(ActionContext context)
        {
            if (Selector == "one")
            {
                DisplayedMessage = $"Hello, {FirstName}!";
            }
            else if (Selector == "two")
            {
                DisplayedMessage = $"Hello, {FirstName} {LastName}!";
            }
            else // The 3rd Selector was chosen 
            {
                DisplayedMessage = $"Hello, {FirstName} {LastName}!\nYour age is: {Age}";
            }
        }
    }
}

[eJackson]

The only problem with this is that to use the ActionSelector functionality, the input argument must be an enum: 

The action selectors allows you to define constraints to match them to the value of the input argument at runtime:

I wanna say I've identified at least one issue within the tests SDK that causes this behavior. There's a function called "ValidateSelectors" in the ActionValidator class that tries to compare the constraint value with the value of the input argument, which is cast to an int. This cast causes the validator to throw an exception when the input argument is a string, leaving us here:

I'd go into more detail but it's honestly quite a bit to go through. 

[kinuasa · Accepted solution]

I understand what you are saying.
I suggest specifying it in Resources instead of in the Description attribute.

using System.ComponentModel;
using Microsoft.PowerPlatform.PowerAutomate.Desktop.Actions.SDK;
using Microsoft.PowerPlatform.PowerAutomate.Desktop.Actions.SDK.ActionSelectors;
using Microsoft.PowerPlatform.PowerAutomate.Desktop.Actions.SDK.Attributes;
using static Modules.CustomModule.CentralCustomAction;

namespace Modules.CustomModule
{
    [Action(Id = "CentralCustomAction")]
    public class CentralCustomAction : ActionBase
    {
        public enum SelectorChoice
        {
            Selector1,
            Selector2,
            Selector3
        }

        [InputArgument, DefaultValue(SelectorChoice.Selector1)]
        public SelectorChoice Selector { get; set; }

        [InputArgument(Order = 1)]
        public string FirstName { get; set; }

        [InputArgument(Order = 2)]
        public string LastName { get; set; }

        [InputArgument(Order = 3)]
        public int Age { get; set; }

        [OutputArgument]
        public string DisplayedMessage { get; set; }

        public override void Execute(ActionContext context)
        {
            if (Selector == SelectorChoice.Selector1)
            {
                DisplayedMessage = $"Hello, {FirstName}!";
            }
            else if (Selector == SelectorChoice.Selector2)
            {
                DisplayedMessage = $"Hello, {FirstName} {LastName}!";
            }
            else // The 3rd Selector was chosen 
            {
                DisplayedMessage = $"Hello, {FirstName} {LastName}!\nYour age is: {Age}";
            }
        }
    } // you can see below how to implement an action selector

    public class Selector1 : ActionSelector<CentralCustomAction>
    {
        public Selector1()
        {
            UseName("DisplayOnlyFirstName");
            Prop(p => p.Selector).ShouldBe(SelectorChoice.Selector1);
            ShowAll();
            Hide(p => p.LastName);
            Hide(p => p.Age);
            // or 
            // Show(p => p.FirstName); 
            // Show(p => p.DisplayedMessage);
        }
    }

    public class Selector2 : ActionSelector<CentralCustomAction>
    {
        public Selector2()
        {
            UseName("DisplayFullName");
            Prop(p => p.Selector).ShouldBe(SelectorChoice.Selector2);
            ShowAll();
            Hide(p => p.Age);
        }
    }

    public class Selector3 : ActionSelector<CentralCustomAction>
    {
        public Selector3()
        {
            UseName("DisplayFullDetails");
            Prop(p => p.Selector).ShouldBe(SelectorChoice.Selector3);
            ShowAll();
        }
    }
}

• Adding descriptions to custom actions
  https://learn.microsoft.com/en-us/power-automate/desktop-flows/create-custom-actions?WT.mc_id=M365-M...
• Setting descriptions for custom action selectors
  https://learn.microsoft.com/en-us/power-automate/desktop-flows/create-custom-actions?WT.mc_id=M365-M... 

[quer13]

@kinuasaYes, great, with the resources it works well. Thank you for this hint. Also, it's more flexibel than the Description-Attribute way.

Do you test more than the default resource file (Resources.res)?

I also created "Resources.de-DE.resx" for german language. Does it work for you, if you choose another language?

PAD does not take the german resource file, although I have a german account and Windows-OS.

[kinuasa]

I was able to localize it by copying the Resources.resx file and renaming it Resources.{locale}.resx file.
This was confirmed in the Power Automate for desktop version 2.35.159.23221 environment (the figure below is in Japanese environment).

[quer13]

Hello kinuasa.

I just noticed that you are showing me file "Resources.resx" and not the localized file. You made your localization in the default english resource file and not in the japanese one.

For me localization is not possible.

It seems that PAD has a bug.