Fix drag annotation blink issue

[Chaoba]

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Fixes: < Link to related issues that will be fixed by this pull request, if they exist >

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• Briefly describe the changes in this PR.
• Include before/after visuals or gifs if this PR includes visual changes.
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Summary of changes

In this pr, we will remove the drag annotation from the drag source only when the map is idle and 1 sec later, so there will be no blink issue after drag.

Before:

device-2021-08-20-142132.mp4

After:

device-2021-09-14-133809.mp4

User impact (optional)

[kiryldz]

@Chaoba Fix drag annotation blink; Apply properties to drag layer is pretty confusing imho.
Please better describe how it was fixed stating that we introduce delay when drag is finished before removing drag source.
Also could you please clarify if all those tests updates are related to drag blink issue? if not - can we move it to a separate PR?

[kiryldz]

Also when I look at the second video when you start dragging annotation again (sec 4-5) it seems that drag start is not behaving as expected, annotation jumps to some position instead of smooth dragging.

[Chaoba]

Also when I look at the second video when you start dragging annotation again (sec 4-5) it seems that drag start is not behaving as expected, annotation jumps to some position instead of smooth dragging.

We still need to remove the dragging annotation from original source, which will trigger the update for all annotations. We can't skip this step in the current architecture. What we currently do is making it better but not the best.

[kiryldz]

Also when I look at the second video when you start dragging annotation again (sec 4-5) it seems that drag start is not behaving as expected, annotation jumps to some position instead of smooth dragging.

We still need to remove the dragging annotation from original source, which will trigger the update for all annotations. We can't skip this step in the current architecture. What we currently do is making it better but not the best.

Why is there no such problem when the very first dragging happens?

[pengdev]

Also when I look at the second video when you start dragging annotation again (sec 4-5) it seems that drag start is not behaving as expected, annotation jumps to some position instead of smooth dragging.

We still need to remove the dragging annotation from original source, which will trigger the update for all annotations. We can't skip this step in the current architecture. What we currently do is making it better but not the best.

Why is there no such problem when the very first dragging happens?

I took a closer look at the first video, I see the annotation being dragged also jumped at the beginning, instead of smooth transition, so in this regard I don't think the behaviour is a regression compared to main branch.

[Chaoba]

I took a closer look at the first video, I see the annotation being dragged also jumped at the beginning, instead of smooth transition, so in this regard I don't think the behaviour is a regression compared to main branch.

Exactly. We have to update all annotations in order to remove the dragging annotation from the original source at the beginning of the drag gesture. Currently we don't have a solution for it.

[pengdev]

@Chaoba one thought, can we keep both layers during the transition? for example, start merging the dragged annotation to the annotation source, and listen to the MapIdle event, when the MapIdle event is triggered, then remove the dragged layer, wdyt?

[Chaoba]

@Chaoba one thought, can we keep both layers during the transition? for example, start merging the dragged annotation to the annotation source, and listen to the MapIdle event, when the MapIdle event is triggered, then remove the dragged layer, wdyt?

That's what we are doing now. But we always keep two layers.