Reload image after a failed load in Jetpack Compose

Is your feature request related to a problem? Please describe.

val painter = rememberImagePainter(url)
Image(
    modifier = Modifier.fillMaxSize(),
    painter = painter,
    contentDescription = null,
    contentScale = ContentScale.Fit
)
when (val state = painter.state) {
    is ImagePainter.State.Error -> {
        TextButton(onClick = { }) { Text("retry") }
    }
}

After a failed load, the user should be able to reload the image via the retry button.

Describe the solution you’d like It is better to provide reload method, but it seems that setting request in ImagePainter to public would also work.

[colinrtwhite]

Still figuring out a good public API for this, but if you need this today you can force retry by changing a parameter:

var retryHash by remember { mutableStateOf(0) }
val painter = rememberAsyncImagePainter(
    model = ImageRequest.Builder(LocalContext.current)
        .data(url)
        .setParameter("retry_hash", retryHash, memoryCacheKey = null)
        .build()
)
Image(
    painter = painter,
    contentDescription = null,
    contentScale = ContentScale.Fit,
    modifier = Modifier.fillMaxSize(),
)
when (val state = painter.state) {
    is AsyncImagePainter.State.Error -> {
        TextButton(onClick = { retryHash++ }) { Text("retry") }
    }
}

Currently, I’m thinking the public API should be something like this, but let me know what you think!

val requestHandle = rememberAsyncImageRequestHandle()
val painter = rememberAsyncImagePainter(
    request = ImageRequest.Builder(LocalContext.current)
        .data(url)
        .requestHandle(requestHandle)
        .build()
)
Image(
    painter = painter,
    contentDescription = null,
    contentScale = ContentScale.Fit,
    modifier = Modifier.fillMaxSize(),
)
when (val state = painter.state) {
    is AsyncImagePainter.State.Error -> {
        TextButton(onClick = { requestHandle.restart() }) { Text("retry") }
    }
}

[FishHawk]

Thanks! I’ll try it later.

The api is indeed a problem. Your example is very similar to focusRequester. I’m ok with it. But since there must be an ImagePainter object here, I think it would be simpler to have an ImagePainter with a retry method.