Dropdown field configuration

RE: Dropdown field configuration

Chris — Thu, 13 May 2021 18:15:13 GMT

Hi Paul, welcome aboard!

To note, there is a wealth of excellent documentation available including samples, best practices, component functionality, available functions, etc. If you haven't become familiar yet, I would definitely recommend doing so! My favorite area is the Interface Patterns.

In regards to the situation in this thread, you can certainly populate List B based on a call to the database via a!queryEntity(), relative to the selection in List A. I have a number of applications which use that type of setup. There are also some cases, depending on data sets, where you may pre-set List B options from the DB into a local variable on form load, then pull specific values from the local var for List B depending on List A (better for performance, in some situations).

For changes in your thought process, I can't really see anything major that would be 'trash' per say as far as logical application design goes - except maybe thinking you still have to build everything from scratch 🙂

Build a few small processes, become familiar with the components and functions, keep tabs on the forum and documentation and you'll be good to go!

RE: Dropdown field configuration

paulp0005 — Thu, 13 May 2021 17:41:31 GMT

Hello Chris (and anyone else who would like to comment),

I am working with a trial version of Appian and so far really like the product and the community.

First, I would like to say this is a really great and active community. It makes you want to be part of it.

Regarding this particular issue and coming from a Windows Client application mentality, I would generally populate List B based on an SQL call using arguments from List A.

So I am wondering how different is the paradigm in THINKING about the architecture? What should I be throwing into the trash heap with a new way of approaching business process oriented applications? What should I embrace? What fundamental changes in thinking are suggested in order to succeed?

Thanks in advance for your thoughts!!

Paul

RE: Dropdown field configuration

Chris — Thu, 13 May 2021 14:26:13 GMT

Great! :)

RE: Dropdown field configuration

GauravSingh — Thu, 13 May 2021 07:04:03 GMT

Thanks Chris

This has helped me 🙂

RE: Dropdown field configuration

Chris — Wed, 12 May 2021 17:17:23 GMT

Hi, here's a sample grid to get us going. This should satisfy your requirements, with the exception of modifying the second column to handle whatever you need for the that dropdown for local!rows[fv!index].col2 based on local!rows[fv!index].col1. This allows a maximum of rows added to match the options list, and removes values from the dropdowns as they are selected in other rows.

a!localVariables(
  local!options: {"ABC","DEF","GHI","JKL"},
  local!rows,
  
  a!gridLayout(
    headerCells: {
      a!gridLayoutHeaderCell(label: "Column 1"),
      a!gridLayoutHeaderCell(label: "Column 2"),
    },
    rows: {
      a!forEach(
        items: local!rows,
        expression: a!gridRowLayout(
          id: fv!index,
          contents: {
            a!localVariables(
              local!ddlOptions: reject(
                fn!isnull,
                append(
                  difference(
                    local!options,
                    a!forEach(
                      items: local!rows.col1,
                      expression: tostring(fv!item)
                    )
                  ),
                  local!rows[fv!index].col1
                )
              ),
              a!dropdownField(
                placeholder: "-- Select --",
                choiceLabels: local!ddlOptions,
                choiceValues: local!ddlOptions,
                value: fv!item.col1,
                saveInto: local!rows[fv!index].col1
              )
            ),
            a!textField(
              readOnly: true,
              value: fv!item.col1
            )
          }
        )
      )
    },
    addRowLink: a!dynamicLink(
      showWhen: count(local!rows)<count(local!options),
      label: "Add a Row",
      saveInto: a!save(local!rows,append(local!rows,{col1: null, col2: null}))
    )
  )
)