Auto-refresh issue on scrolling in dropdown of 100+ choices with 1+ null choice label, on a monitor

Certified Associate Developer

This is an issue that was initially reported on a Site and I could not replicate it when testing in any browser, until I thought to test on a separate monitor (not my laptop screen). When testing on the monitor was able to replicate in Chrome & Edge through the Site, through the top-level parent interface, and through the interface that contained the dropdown (although for the customers instead of a refresh, it was causing the entire page to turn grey). Can only replicate the issue on my laptop screen through the interface, not through the Site. I have reached a resolution for the issue (updating/deleting rows in the database or logic on local!choices to replace nulls with "Unknown") but sharing since I was not able to find anything when I had searched online. Believe the issue was caused by a user deleting some of the data for a couple rows before using the "Delete" icon/button that had been set up.

The case was the query pulling in the data did not have any filters & there were couple similar fields in the database: code, desc, name. The queried data was sorting on the code (always not null) & using the desc (couple nulls) as the Choice Labels (IDs as the Choice Values, all unique integers). Below is some code that can be copy-pasted into a test rule if anyone would like to see what the issue looks like, just need to do the testing on a separate monitor (not your laptop screen).

a!localVariables(
  local!values: enumerate(105),
  local!choices: touniformstring({enumerate(15), "", enumerate(89)}),
  local!selection: null,
  a!sectionLayout(
    contents: a!dropdownField(
      label: "Dropdown",
      placeholder: "-- Select a Value --",
      choiceLabels: local!choices,
      choiceValues: local!values,
      value: local!selection,
      saveInto: local!selection
    )
  )
)

  Discussion posts and replies are publicly visible

  • 0
    Certified Senior Developer

    when you are configuring choice labels and choice values for a dropdown , make sure you have null check for these choices and values. you will not face this error.

  • +1
    Certified Lead Developer

     this seems to be a bug. I attached a video showing the behaviour.

  • 0
    Certified Senior Developer

    What I understood is that the choice values are the Ids that are not null but the choice labels are non id fields that are nullable, here you need to put a filter on the query to return only that data which will not have nulls in the field used in the choice labels. 

  • 0
    Certified Associate Developer

    Hi,

    Slight correction in your code hope it will help you for the null values

    a!localVariables(
      local!choices: reject(fn!isnull,touniformstring({enumerate(15), "", enumerate(89)})),
      local!values: enumerate(count(local!choices)),
      local!selection: null,
      a!sectionLayout(
        contents: a!dropdownField(
          label: "Dropdown",
          placeholder: "-- Select a Value --",
          choiceLabels: local!choices,
          choiceValues: local!values,
          value: local!selection,
          saveInto: local!selection
        )
      )
    )

  • 0
    Certified Lead Developer
    in reply to Stefan Helzle

    Not sure if it is only for me - 

  • 0
    Certified Lead Developer
    in reply to Harshit Bumb (Appyzie)

    I changed the format to mp4. Does that work for you?

  • 0
    Certified Associate Developer
    in reply to Stefan Helzle

    Right, thanks Stefan. This was just a test script since I cannot show the actual data, but it was a dropdown that needed to include deleted/historical values so they did not want any filters applied. I had to meet with them to get confirmation on how to update the database to resolve the issue, it is fixed now, so just wanted to share in case anyone else runs into this issue.

  • 0
    Certified Associate Developer
    in reply to shuaibs0003

    This was just a test interface to show/explain a bug. The actual interface had ID fields from a database as the Value & Description fields from a database as the Choices. A description had not been added to 3 of the 100+ rows. Having a dropdown with 100+ choices but 1 or more of them being blank causes this issue (Stefan replicated it & added a video).

    I had forgotten to mention in the post originally, but for the users, this issue was causing the entire page to turn into a gray screen (needing to manually refresh the web-page to fix). But for me it was looking like a page refresh, although selected values on the page were being retained for me.

  • 0
    Appian Employee
    in reply to stevene0005

    Yes this does look like a bug to me - I was able to replicate it as well. Would you mind opening a support case to submit this? That makes it easier for us to track this Slight smile

    Thanks for reporting!