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Handle partial visibility state

See original GitHub issue

Requirements for our project have visibility tracking of elements at 50% visibility. Since both VisibilityState.FOCUSED_VISIBLE and VisibilityState.FULL_IMPRESSION_VISIBLE do not cover this state, we were thinking of extending the visibility tracker.

The idea would be to offer some api to define a threshold (range 0…1) for when a visibility state would be triggered. This could either be applied to the VisibilityState.FULL_IMPRESSION_VISIBLE, which would redefine what a full impression is in the app context, or preferably introduce a new state VisibilityState.PARTIAL_IMPRESSION_VISIBLE. Implementation would be very similar to VisibilityItem#handleFullImpressionVisible.

Now we could probably handle this using the visibilityChanged, but it would be more involved to not double-count the impression and it would trigger quite often (so we would not be able to disable the noisy onChanged (visibilityChangedEnabled).

I think there might be more use-cases which would warrant to have a single-event impression for a certain threshold of visibility. If you think it might be useful, I will whip up a PR within the next weeks.

Issue Analytics

State:
Created 4 years ago
Comments:6 (6 by maintainers)

Top GitHub Comments

1reaction

eboudrantcommented, May 3, 2020

Thanks, I added few comments but overall looks good.

Could you clarify “defining a list of thresholds”? I think the only case were we wanted to use it would be with one threshold only. Do you need multiple?

1reaction

mediavrogcommented, Apr 21, 2020

Hi @eboudrant, sorry for leaving this discussion for a long time. I have created a draft of a PR over at https://github.com/smartnews/epoxy/pull/1/files, could you please give feedback on the general direction of this approach? Does this seem reasonable?

TODO

tests
threshold _INVISIBLE state?

Do you think one threshold would be ok, or should it support defining a list of thresholds?

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