Improve removing spans on Android

[tomekzaw]

Details

This PR changes the way how spans are removed before applying new formatting.

Previously, we would call ssb.getSpans(0, ssb.length(), MarkdownSpan.class) to find all span added in the previous run. All added spans implement MarkdownSpan interface.

After this change, each time we add a span, we add it to mMarkdownSpans list (ArrayList). Then, we iterate over that list to remove all previously added spans and clear the list afterwards.

Related Issues

GH_LINK

Manual Tests

Linked PRs

[j-piasecki]

The code looks good but what's the reasoning behind this change?

[tomekzaw]

There's no particular reason for this change right now. Android spans are known to be slow and I want to see if we can make it faster by eliminating ssb.getSpan call in favor of keeping a list of spans.

[tomekzaw]

I've tested out this change on Google Pixel 4 in release mode with profiler attached and removeSpans takes 1.09 ms vs. 1.12 ms. In debug mode, removeSpans takes ~3ms.

So there's no rush to get this PR merged as the performance is comparable.