Ben Nham 71bf8a3e48 Only clear image contents on memory warning
Summary:
Some apps are complaining about flashing images when performing navigation transitions. An example issue would be:

1. Load a master list view with many images
2. Click on an image to go to a detail view
3. Go back to the master list view

At step (3), users see a number of images flash from a placeholder image back to the final image because `-[RCTImageView didMoveToWindow]` calls `clearImage` when the image view exits the view hierarchy between (1) and (2) and calls `reloadImage` (which sets the image property asynchronously) when the image view re-enters the view hiearchy between (2) and (3).

This diff fixes the issue by being less aggressive about clearing image contents. It only clears image contents when the app receives a memory warning or the app goes into the background.

For comparison, CKNetworkImageComponent in ComponentKit doesn't have this purging behavior at all.

Reviewed By: javache

Differential Revision: D3325009

fbshipit-source-id: efca10099cdfdb49afbb3f550854d4b8a40511d0
2016-05-24 08:43:23 -07:00
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2016-04-27 19:16:32 -07:00
2016-05-20 18:43:38 -07:00
2016-04-06 09:21:53 -07:00
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