Hello, is there a way to detect whether a composab...

# compose-android

[louiscad]

Hello, is there a way to detect whether a composable is run…?:
• in interactive preview within Android Studio / IDE
• in static preview within Android Studio / IDE
• deployed as an interactive preview on a phone
• just in an app "normally"

[ephemient]

not sure why you'd want to, but
• LocalInspectionMode.current && LaunchedEffect { ... } runs
• LocalInspectionMode.current && LaunchedEffect { ... } doesn't run
• never tried but maybe LocalContent.current.packageName.endsWith(".test")

[louiscad]

Problem with LaunchedEffect is the first composition is off

[louiscad]

It's fine in IDE preview, but it's not fine in production

[Stylianos Gakis]

DisposableEffect should happen on the first composition

[yschimke]

The interactive preview on a device is false for LocalInspectionMode.current

[yschimke]

This is an example for switching on interactive/static previews in IDE https://github.com/google/horologist/blob/91b797b563557580968bcc67d8550d1518c8aea0[…]gle/android/horologist/compose/tools/InteractivePreviewAware.kt

it has the same first frame, and then once a LaunchedEffect runs, knows it's interactive.

[louiscad]

You're all right, my concern for initial composition in production isn't valid since LocalInspectionMode.current will always tell me it's not in the IDE

[yschimke]

I think you have everything you need. You can detect device preview with something like

https://github.com/VincentMasselis/TPMS-advanced/blob/76971a405a98a4f3aac59c5b0581[…]c/main/kotlin/com/masselis/tpmsadvanced/core/ui/KeepScreenOn.kt

Since it's how previews are launched IIUC https://cs.android.com/android-studio/platform/tools/adt/idea/+/mirror-goog-studio-m[…]gurationTest.kt?q=androidx.compose.ui.tooling.PreviewActivity

[louiscad]

LaunchedEffect is actually run for a short amount of time for static preview, so it fails me 🥹

[louiscad]

My sad workaround is to add delay(16). I tried calling yield() a few times, up to 60 times, and it never worked. delay(1) isn't either, but delay(16) is.

[louiscad]

delay(16) isn't always working, delay(33) seems to work more consistently.
I wish I didn't have to do this kind of hack with magic numbers.
I'm interested in any other solution, but I'll stick to that for now.