Images disappear while in return transition

[jventrib]

Hello,

Describe the bug
I'm using Jetpack Navigation with shared elements transition between fragments. When my detail fragment is returning to home fragment, images in detail fragment disappear as soon as the transition (MaterialContainerTransform) is initiated. It seems that ViewTargetRequestDelegate.dispose() is called at the beginning of the transition, causing the image to be cleared.

Expected behavior
I expect the images to be displayed (and fade) during the transition. This is working correctly when Glide is used instead of Coil.

To Reproduce
The simpliest I found to reproduce is to take the Reply app from Material-components-android-examples and replace the glide image loading in BindingAdapter.kt with Coil. I see the same behaviour with my own app.

Logs/Screenshots

With Coil

With Glide

Version
Coil 1.1.1

Thank you in advance !

[kroegerama]

I'm so glad I found this bug report. At first I thought it was a bug in the material design library. They have a bug open, too. But it's seems to be the fault of the image loading frameworks.

Keywords for anyone with the same problem: Coil preserve image during return transition ImageView ShapeableImageView

[colinrtwhite]

I haven't tested myself, but if you set lifecycle(activity) on your ImageRequest does it work around the issue?

[kroegerama]

Just tested lifecycle(requireActivity()) but sadly didn't help.

[colinrtwhite]

Setting a custom target should hopefully work around the issue:

val request = ImageRequest.Builder(context)
    .data(url)
    .target { imageView.setImageDrawable(it) }
    .build()
imageLoader.enqueue(request)

[jventrib]

I can confirm that setting a custom target fix the issue !
Thank you.

[kroegerama]

So is this the intended way? Don't really want to put any hacks in production code :)

[kahakai]

So is this the intended way? Don't really want to put any hacks in production code :)

I don't think this is the intended way, but it might be the only way to workaround the problem as it was found out here after the research: facebook/fresco#1445 (comment)
Maybe this can be fixed on the library side.

[ardyfeb]

Setting a custom target should hopefully work around the issue:

val request = ImageRequest.Builder(context)
    .data(url)
    .target { imageView.drawable = it }
    .build()
imageLoader.enqueue(request)

val cannot be reassigned

I use imageView.setImageDrawable(it) instead

[ianhanniballake]

Note that it is expected behavior from the Android framework side that any Transition will detach the views from their window (thus triggering any disposal associated with onDetachedFromWindow()).

To fix this, you'd need to disable that behavior and only rely on the LifecycleOwner reaching DESTROYED (e.g., for Fragments, the viewLifecycleOwner only reaches DESTROYED once the Transition fully completes). Is that possible to do right now with Coil?

[colinrtwhite]

@ianhanniballake Yep, we could probably add an option disable the detach behaviour (like how using a non-ViewTarget disables it) though this would require enabling it manually. I'm planning to address this bug in 2.0 by removing the automatic ImageView clearing behaviour since it's mostly needed for bitmap pooling which is also going away.

EDIT: This issue is fixed in the 2.0.0-alpha01 and newer releases of Coil.