expose updateImageState to parent components

[theolampert]

adds a separate updateImageState to allow a parent component to trigger an image reload

[paulstraw]

This seems fine to me, but I'm not an expert in React idioms. @frederickfogerty?

[frederickfogerty]

@theolampert

What are your goals with this change? I'm assuming you want it to recalculate the styles based on a change in width/height? To cover that use case, I'm looking at (and would prefer) the use of DOM Mutation Observers, which pick up these changes without having to call updateImgState directly.

Am I right in thinking the intended api for this is this.refs.Imgix.updateImgState()? If it's for the use case described above, I think a name like forceLayout() or recalculateStyles() would be much more fitting.

In terms of whether I think this is an acceptable PR, I think yes. Even though we will implement Observers (as above), I think this is still necessary, perhaps for older browsers or other scenarios.

Please let me know if I'm completely on the wrong course.

[theolampert]

@frederickfogerty yes you're correct - I ran into an issue at work where we needed this, sorry for not being clearer above. I think forceLayout() works well, I'll update the pr if you're happy with that.

[frederickfogerty]

Okay cool. If you can squash your commits with a useful commit message I'm happy to merge. There's going be some issues here with unmounted components but I'm going to open a seperate issue for that, as it's not directly related to this PR.

[theolampert]

@frederickfogerty commits are squashed and renamed now.

[frederickfogerty]

Merged and released in v2.2.0