Support Altair HTML charts

[joelostblom]

When I run Altair code, I don't see any output, not even a textual representation of the chart. For example:

import altair as alt

alt.Chart().mark_point()

I also tried rendering the HTML via IPython display, but the following code gives the same empty output (html text renders fine in HTML):

import altair as alt
from IPython.display import HTML

HTML(alt.Chart().mark_point().to_html())

I initially thought that this might be the same issue as coatless-quarto/pyodide#7, but there a textual output is shown which indicates that altair detected that the frontend can't render the chart and doesn't produce the HTML version of the chart. In quarto-live, it seems like the HTML version of the chart is produced, but that something is interfering with displaying it. Is this the same issue as quarto-dev/quarto-cli#3424? If so, is there anything that can be done from the altair-side of things to make support in quarto easier?

[joelostblom]

Given that it seems like plotly plots are also not working as per #47, I'm thinking what I reported here is a different issue than quarto-dev/quarto-cli#3424, but it would be great to have some more insight here.

[georgestagg]

Yes, I think this is related to #47, but a distinct problem.

With some manual prodding in the JS console, I can get the plot to at least display - so it is possible this can work.

I'm going to deal with #47 first, as it will be required for this Issue too, then return here and continue to investigate.

[joelostblom]

Exciting! Thank you for looking into this!

[georgestagg]

As of e33a900 this should now work! I've added an example to the docs here:

https://r-wasm.github.io/quarto-live/other/py_output.html#example-altair-interactive-visualisation

I'm going to close this for now, but feel free to comment below if any particular features of Altair are broken and we can re-open to investigate :)

[joelostblom]

Wohoo! That's so great to see; thanks for the quick resolution!