[Android] Support for Image onError

[MichaelDanielTom]

Hey Guys,

Will there be support for an onError callback on Image for Android? I want to set an error image if the image fails to load, without resorting to hacking around onLoad and onLoadEnd. If I'm overlooking an obvious easy way to do this please let me know :)

[brentvatne]

68b2f49 adds support for this to an extent, but it's not perfect -- it doesn't handle some cases like 404s which Fresco (the underlying image library) doesn't handle yet afaik, cc @tyronen

[ide]

The Java implementation of Image.prefetch calls the rejection callback on error so Fresco might expose errors now, worth revisiting.

[ajoshdee]

Same with ios, i want to set default image onError, dunno how.

[atticoos]

@ajoshdee, you'd need to make a component that handles the error, sets a state indicating there's an error, and then using that default image when an error exists

[SergeyKorochansky]

@brentvatne This 68b2f49 commit adds event dispatching, but JS component does not receive it (but onLoadEnd works great). Why it happens?

[lacker]

We closed the referenced pull request as "working as intended" so I think we should close this issue as well.

[atticoos]

@lacker it sounds like the conclusion there is that onError will not currently work on Android. Would prefer to keep an issue open for visibility, discussions, and future outlook

[lacker]

Our goal right now is to focus the github issues for bug reports - it had been months on this anyway with no activity. If someone has a proposal for how to fix this then I think it would be worth opening another issue to debate it.

[atticoos]

Sounds good @lacker - thanks for explaining.

Dropping this here for anyone that comes seeking this issue, this is a solution we threw together to achieve the platform consistency:

https://github.com/robinpowered/react-native-android-image-polyfill
https://www.npmjs.com/package/react-native-android-image-polyfill