* Update refs-and-the-dom.md
I want to propose some changes to the Refs and the DOM documentation page.
- Make it clear that string refs are legacy. It seems that this information got lost during the transition to new docs and only some part stayed the same, which was confusing when first reading the docs.
- Clarify and explain that during render, if the ref callback is provided, it will get called twice, first with `null` and then with the rendered DOM element. Discussed in https://github.com/facebook/react/issues/4533 and first proposed docs change in PR #8333.
I've also planned on adding an example for passing the refs up the component chain based on something I've needed to solve myself (e.g. you want to connect two dynamic components by line in React, so you need to both use refs and propagate them up the chain), and while it would be great to read up on this in the docs, it may be too specific for this section; I'd be happy to hear any recommendations.
* Adds more specific information about the callback
* Moved the ref callback description to the Caveats section
* Fixed suggested nits
* Replace 'each render pass' with 'updates'
* Tweak the wording
* Fix typo in Proposing a Change section in how-to-contribute.md
Not sure if it was actually intended or was a typo but changed 'If you intend to change to the public API' --> 'If you intend to make a change to the public API'
* Simplify
* Component Lifecycle In Depth documentation
* first steps to improve react component reference
* improved react component reference
- remove the component-lifecycle-in-depth
* add a note for usage of ReactDOM.findDOMNode
* one note on componentWillReceiveProps
* remove old useless images for lifecycle docs
* Tweak wording
- In the previous example, the code works even without using bind(this) in the constructor.
- the reason being handleClick doesn't even use `this` and its just calling the global function alert.
- this change make use of this via access this.state.
My first contribution to React!
While upgrading a React project, I found some suspect SVG that needed updating, so I dug in after checking the docs. I knew that support for some SVG properties had been added (namely `xmlns` and `xmlnsXlink`), but I noticed them missing from the reference's attribute list. This pull request updates `reference-dom-elements.md` by adding said properties.
Only declare the variable once in this scope, instead of declaring them multiple times in the same scope.
This fixes#8318, even though it might technically be a shortcoming in Rollup.
