Hey Discourse team, I’m currently investigating why Babble slows down user input so much while typing. I’ve traced it to the keyUp / keyDown hooks in my composer widget, which do things like listen for submit on enter, and escape to cancel, as well as sending notifications that the user is currentl…

Hmm this is tricky. The widget framework is designed to re-render following any input, be it clicking or pressing a key. In general re-rendering widgets is fast, so the thought was you should be able to re-render as fast as the user is typing. Are your renders slow? You can output how many ms are b…

My guess would be that the render may be slow because it’s traversing up the widget tree and rerendering the whole chat pane (including all of the posts, which are their own widget), whereas if it rerenders on keyUp I’d love it to just rerender the composer (which I reckon would be quite fast). - s…

Okay, I can confirm this. With a small amount of posts loaded in the window, the rendering times are acceptable (40-60ms each for keyUp / keyDown) However, as more posts are loaded into the window, the rendering time of the widget gradually increases: 50 posts: ~50ms 100 posts: ~70ms 150 posts: …

Are the posts in the window using the shadowTree property that our post stream does? If you set that attribute, the virtual dom will not diff the contents of posts on a typical re-render. It will diff if something inside the post triggers the render (such as an action on a button on it). You might…

Rerendering on widget keyUp / keyDown?

Development

gdpelican (James Kiesel) May 1, 2017, 11:32pm 6

Cool, I think that’s exactly what I’m looking for!

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Rerendering on widget keyUp / keyDown?

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