Jetpack compose can't preview after updating to 1.0.0-rc01

Question

this happened to me only when I updated to 1.0.0-rc01. it says:

The following classes could not be found: - androidx.compose.ui.tooling.preview.ComposeViewAdapter (Fix Build Path, Edit XML, Create Class)

my code:

@Composable @Preview fun CenterProgress(){     Box(         modifier= Modifier.fillMaxSize(),         contentAlignment = Alignment.Center     ){         CircularProgressIndicator(strokeWidth = 3.dp)     } } 

Answer 1

Update 07/20/2021: Just download and use the latest AS to fix the problem

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They splitted some packages in rc01 but per @CommonsWare comment (all credits to him) it seems there is a problem with Android Studio version itself. You have 2 options:

1. Downgrade to beta09 until AS ArcticFox RC1 is out
2. Try the suggested workaround, use AS Arctic Fox Beta 5 leaving all compose dependencies to 1.0.0-rc01 version and downgrade only ui-tooling to 1.0.0-beta09 (confirmed by comments).

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Extra details

Here you can find all the classes they moved in 1.0.0-rc01 https://android-review.googlesource.com/c/platform/frameworks/support/+/1739498 and the explanation on why this has been decided.

In short, you can now do this for some particular optimized scenarios (which should not be the default case):

debugImplementation "androidx.compose.ui:ui-tooling:1.0.0-rc01" implementation "androidx.compose.ui:ui-tooling-preview:1.0.0-rc01" 

Answer 2

Update: This is no longer needed with Android Studio Bumblebee | 2021.1.1 Canary 6 and Android Gradle Plugin 7.1.0-alpha06. Note: Canary 4 already fixed this issue but required a broken version of AGP. This is now also resolved.

In addition to the above answers: here is how to force the ui-tooling version in gradle:

implementation("androidx.compose.ui:ui-tooling:$compose_version") {     version {         // TODO: Remove this when Android Studio has become compatible again         // Android Studio Bumblebee | 2021.1.1 Canary 3 is not compatible with module ui-tooling 1.0.0-rc01 or higher.         // The Run Configuration for Composable Previews that Android Studio makes expects a PreviewActivity class         // in the `androidx.compose.ui.tooling.preview` package, but it was moved in 1.0.0-rc01, and thus causes error:         // "androidx.compose.ui.tooling.preview.PreviewActivity is not an Activity subclass or alias".         // For more, see: https://stackoverflow.com/questions/68224361/jetpack-compose-cant-preview-after-updating-to-1-0-0-rc01         strictly("1.0.0-beta09")     } }