`renderItem` will be called when user scroll the slide

When scrolling the slide, the renderItem method will be called many times. It’s a performance issue.

Related code: https://github.com/xiaolin/react-image-gallery/blob/master/src/ImageGallery.jsx#L1037

It’s because of we will call the method every time when the slide rerender. When the user scrolls the slide, we need to change the style, it will cause re-render.

I guess we don’t need to call the renderItem every time when the style change.

And also, I suggest adding a note in README to suggest return a pure component. Could we change this one to return a PureComponent: https://github.com/xiaolin/react-image-gallery/blob/master/src/ImageGallery.jsx#L885

If you are okey with this, I can help to send a PR.

[xiaolin]

Fixed in 1.2.6 https://github.com/xiaolin/react-image-gallery/releases/tag/v1.2.6

[sachitram-cv]

@xiaolin Is this fixed?

Thanks.