Add support for new context API

[jscottsmith]

Use React 16.3.0 new context API.

• Update the <ParallaxProvider> and <Parallax> to use new context API
• Document usage of controller methods with new context changes
• Support old API for accessing controller methods
• Add new tests/Fix broken tests

[olehreznichenko]

Just want to add
create-react-context - for supporting old react

[pavelhamrik]

Hi guys, I just can't get the context working.

I'm not using PropTypes to start with, nor do I want to, nor doe the React docs on Context mention using it like that.

Is there a way to get it working without PropTypes?

I tried, as documented in React docs:

• MyClass.contextType = ParallaxController; after declaring MyClass
• <ParallaxController.Consumer/> wrapping the component
• static contextType = ParallaxController; inside MyClass

this.context remains an empty object in these cases.

Is the new API really already supported? Or is there a new new API?

[jscottsmith]

New API is not supported, sorry. Hoping to finish an alpha soon using new API and fixing some other issues.

You'll need to use the old context API on the current version.

[pavelhamrik]

Understood. Thank you for the answer and your effort in upgrading the lib!

[jscottsmith]

will fix in v2. See #47