Launch Collect from a browser, with feature pre-selected

spwoodcock · March 17, 2024, 10:54am

Hi @LN !

We finally got around to prototyping this during a tech team meeting with NAXA.
@zestyping was able to pull together a quick working solution for loading entities via an intent.

github.com/hotosm/odkcollect

Launch forms via odkcollect:// links, with entity preselection

hotosm:master ← hotosm:ping/entity-preselection

opened 09:02AM - 17 Mar 24 UTC

zestyping

+48 -1

This proof of concept enables the use of a browsable link to launch the FormFill…ingActivity on a specific form. A query parameter in the link can also preselect an entity in the form. The implementation consists of three parts: 1. Add an `<intent-filter>` to the manifest entry for FormFillingActivity, which catches URLs that begin with `odkcollect://form/` 2. Add a branch in the FormLoaderTask that handles an incoming intent with this kind of URL by looking up a specific form by its Form ID (e.g. "trees_follow_up") rather than its internal id (e.g. "forms/2"). 3. Add a method `preselectEntity` that pre-answers a question in the form, according to a query parameter in the URL. The parameter name should match the name of the question, and the parameter value should be the UUID of the entity. With these changes, a webpage with a link such as the following will launch ODK Collect into the form filling flow, for a specific form, with an entity preselected: ``` Launch a form: <a href="odkcollect://form/trees_follow_up?tree=71297c7d-6a22-4354-b08a-3fbee155d74e"> trees_follow_up </a> ``` For testing, the above HTML is available here so you can load it on a phone browser: https://zestyping.github.io/odkform

To answer your specific questions:

Do all deep links have to be registered with the Play Store?

They only have to be registered on the Play Store if they are HTTP links.
If using the URL protocol as collect://xxx, this isn't an issue.
If the requirement is to have the links identified and hyperlinked within other apps (like whatsapp), then we probably need to use http:// as the protocol and register a verified link on the Play Store, but this is more involved.

Are there any considerations that have to be made up front if we'd like the same links to eventually be deferred deep links that open the Play Store if collect is not installed? Or maybe supporting these links offline is not important because forms have to be downloaded for any work to be possible anyway.

I don't think this is an issue if using a custom protocol collect://.
Further research may need to be done around loading the Play Store ODK Collect listing via an intent, if this is required.
The URL example links to an entity, but to better align with the Central API convention, we may want to use a structure like: /project/ID/entity/ID.

Additional Considerations

The PR allows us to build a custom ODK Collect APK and launch directly with an entity pre-loaded.
We could potentially do what we need without using the entities feature, but think it is best to integrate with the existing entity-based solution (I assume this would be useful to a wider range of users).

Discussion

Are other users potentially interested in this feature?
If we fleshed out the PR and added test cases etc, would this be something you are willing to support in Collect?

@Ivangayton @Nishon @varun2948 @Niraj_Adhikari