Hi, I have been investigating why some Elements randomly pop in front of other in our app. This has revealed a bug in the lightning’s zSorting algorithm, it does not sort Elements with the same zIndex by updateTreeOrder.
The issue is on sortZIndexedChildren of ElementCore, on lines 2062 “// Merge-sort arrays;” it assumes both arrays are sorted, however same zIndex items may not be (since _updateTreeOrder change does not trigger _zIndexResort = true the a array may have unsorted items)
The logic that ensured this was removed on version 1.0.4: performance(updateTreeOrder): refactor, make simpler and (in most cas… · rdkcentral/Lightning@38285e0 · GitHub
Any ideas on how to fix it?
Can you file this as an issue on the Lightning github - Thanks! @michiel FYI
Hi, I have posted the plaayground example of the issue as requested:
- To see the bug press left.
- Can see the issue with _updateTreeOrder not begin sorted by pressing right (after pressing left).
- Can fix the zSort algorithm by pressing down.
Is it clear? Can you understand the bug?
All the PRs were merged I assume this was fixed… I think the bug just needs to be closed…
I am not sure what you mean. Can you not reproduce the bug with the Playground example?
You’re probably referring to this PR fix: order same zIndex elements by updateTreeOrder by jorge-graca-sky · Pull Request #441 · rdkcentral/Lightning · GitHub
That one hasn’t been merged yet and unfortunately didn’t make our latest January release because we needed a bit more time to validate the changes (and any impact they may have).
I believe for the upcoming April release we should be able to work through this PR and get it included in the release.
Tagging @uguraslan for awareness - let’s make sure we pick this PR up.