Tyler-Lopez
commented
12 hours ago Oh - and I want to mention: that my minimum reproducible example is extremely simplified. I want to get ahead of a previous comment/question which was:
Why is this necessary? The layer won't be drawn if there's no data for it.
So, why is it necessary to remove a line cartesian layer dynamically?
It is necessary if the inputs themselves are completely dynamic. In my minimal example, they are over-simplified and not dynamic - so you could just leave the layers without removing them.
However, imagine if a parameter to the Composable was a list of "data series", like List<Triple<Double, Double, DataSeriesType>> where DataSeriesType could be a COLUMN or LINE.
Rather than, within the Composable, deciding what to show, it is state-hoisted and provided to it.
In that case, when you update the list to remove a line, you have no choice but to remove the layer with it.
If this is confusing just let me know and I can write out a full example along these lines.
How to reproduce
Background
I posted this same issue before as a Discussion Question. A point was made which at the time, made sense to me. This point was that, regardless of the error, the approach I was taking was unnecessary - I should not be dynamically adding or removing LineCartesianLayer.
However, I no longer feel this is unnecessary. So, I am opening this as a Bug - I think that is more correct than the original Question.
The problem is that you get the following crash when you dynamically remove a LineCartesianLayer.
Crash: https://gist.github.com/Tyler-Lopez/b8feff82b168366f3b1e5d3b2cce66f6
Reproducible Minimal Example: https://gist.github.com/Tyler-Lopez/0358e74977973034b7559ae7a172114b**
Motivation For Why This Should Work
The error is NOT reproducible when a ColumnCartesianLayer is dynamically removed. That can be tested by hitting the second switch in the above example.
It is an expected competency to be able to nest a bar chart between two lines. If those two lines must share the same layer to avoid this crash when one is removed, it is not possible to do this.
Other Note
I would love if, when cartesian layers were added & removed, they did not "reset" the chart. That is one really nice benefit to only use a single
LineCartesianLayer: when you add and remove series from it, it doesn't reset the chart, it just animates in or out that one series.Demo
https://github.com/user-attachments/assets/4d256212-0c18-42ea-a178-687e242fe652
Observed behavior
Removing (but not adding) a LineCartesianLayer crashes.
Expected behavior
Removing a LineCartesianLayer should not crash, like how the ColumnCartesianLayer removal doesn't crash.
Vico version(s)
2.0.0-beta.1
Android version(s)
33
Additional information
No response