pesterhazy

So you want to write a sync system for a web app with offline and realtime support? Good luck. You might find the following resources useful.

Overview articles

• Database in a browser, a spec (Stepan Parunashvili)

  What problem are we trying to solve with a sync system?

• The web of tomorrow (Nikita Prokopov)

azagniotov

Create beautiful REST API docs authored in Markdown

• Adopted from: https://stubby4j.com/docs/admin_portal.html
• Inspired by Swagger API docs style & structure: https://petstore.swagger.io/#/pet

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Creating new/overwriting existing stubs & proxy configs

slikts

Advanced memoization and effects in React

Memoization is a somewhat fraught topic in the React world, meaning that it's easy to go wrong with it, for example, by [making memo() do nothing][memo-pitfall] by passing in children to a component. The general advice is to avoid memoization until the profiler tells you to optimize, but not all use cases are general, and even in the general use case you can find tricky nuances.

Discussing this topic requires some groundwork about the technical terms, and I'm placing these in once place so that it's easy to skim and skip over:

• Memoization means caching the output based on the input; in the case of functions, it means caching the return value based on the arguments.
• Values and references are unfortunately overloaded terms that can refer to the low-level implementation details of assignments in a language like C++, for example, or to memory

slikts

Why using the children prop makes React.memo() not work

I've recently ran into a pitfall of [React.memo()][memo] that seems generally overlooked; skimming over the top results in Google just finds it mentioned in passing in a [React issue][regit], but not in the [FAQ] or API [overview][react-api], and not in the articles that set out to explain React.memo() (at least the ones I looked at). The issue is specifically that nesting children defeats memoization, unless the children are just plain text. To give a simplified code example:

const Memoized = React.memo(({ children }) => (<div>{children}</div>));
// Won't ever re-render
<Memoized>bar</Memoized>
// Will re-render every time; the memoization does nothing

sebmarkbage

The Rules of React

All libraries have subtle rules that you have to follow for them to work well. Often these are implied and undocumented rules that you have to learn as you go. This is an attempt to document the rules of React renders. Ideally a type system could enforce it.

What Functions Are "Pure"?

A number of methods in React are assumed to be "pure".

On classes that's the constructor, getDerivedStateFromProps, shouldComponentUpdate and render.

glen-cheney

Encoding Video

Installing

Install FFmpeg with homebrew. You'll need to install it with a couple flags for webm and the AAC audio codec.

brew install ffmpeg --with-libvpx --with-libvorbis --with-fdk-aac --with-opus

gabrielemariotti

You can use this class to realize a simple sectioned RecyclerView.Adapter without changing your code.

The RecyclerView should use a LinearLayoutManager. You can use this code also with the TwoWayView with the ListLayoutManager (https://github.com/lucasr/twoway-view)

This is a porting of the class SimpleSectionedListAdapter provided by Google

Example: