I started with this documentation Launching External Apps — ODK Docs
where the example here on specifying a URI
Launching External Apps — ODK Docs
uses SENDTO and DIAL to link to sms and telephone call and thought the same technique with VIEW could be used to access a web app to fetch data for a single field.
In the same way as the “url” appearance creates an “Open url” button to go to an external web app, I hoped that this solution, which creates a “Launch” button in Kobo/ODK Collect would enable me to return a value from a web app rather than use cut&paste as is needed when using the “url” appearance.
The XLSForm shows the two approaches tested
The problem I am trying to solve is this:
I have a small web app that converts GPS coordinates to PlusCodes in the same way that https://plus.codes/api?address=48.85,2.29 does. However, since the web app caches, it works offline in the field and enable surveyers to use the PlusCodes to share en ID based on this. With the “Open url” solution I can send the coordinates to the app and it returns a Pluscode to the clipboard but the user then needs to 1)close the web app, 2)paste the value into a text field. I was hoping that the method with ex:android.intent.action would enable me to remove this inconvenience and return the value without the manual paste operation.