CameraX update makes dual concurrent camera even easier

// Set up primary and secondary camera selectors if supported on device.
var primaryCameraSelector: CameraSelector? = null
var secondaryCameraSelector: CameraSelector? = null

for (cameraInfos in cameraProvider.availableConcurrentCameraInfos) {
    primaryCameraSelector = cameraInfos.first {
        it.lensFacing == CameraSelector.LENS_FACING_FRONT
    }.cameraSelector
    secondaryCameraSelector = cameraInfos.first {
        it.lensFacing == CameraSelector.LENS_FACING_BACK
    }.cameraSelector

    if (primaryCameraSelector == null || secondaryCameraSelector == null) {
        // If either a primary or secondary selector wasn't found, reset both
        // to move on to the next list of CameraInfos.
        primaryCameraSelector = null
        secondaryCameraSelector = null
    } else {
        // If both primary and secondary camera selectors were found, we can
        // conclude the search.
        break
    }
}

if (primaryCameraSelector == null || secondaryCameraSelector == null) {
    // Front and back concurrent camera not available. Handle accordingly.
}

// If 2 concurrent camera selectors were found, create 2 SingleCameraConfigs
// and compose them in a picture-in-picture layout.
val primary = SingleCameraConfig(
    cameraSelectorPrimary,
    useCaseGroup,
    CompositionSettings.Builder()
        .setAlpha(1.0f)
        .setOffset(0.0f, 0.0f)
        .setScale(1.0f, 1.0f)
        .build(),
    lifecycleOwner);
val secondary = SingleCameraConfig(
    cameraSelectorSecondary,
    useCaseGroup,
    CompositionSettings.Builder()
        .setAlpha(1.0f)
        .setOffset(2 / 3f - 0.1f, -2 / 3f + 0.1f)
        .setScale(1 / 3f, 1 / 3f)
        .build()
    lifecycleOwner);

// Bind to lifecycle
ConcurrentCamera concurrentCamera =
    cameraProvider.bindToLifecycle(listOf(primary, secondary));

// If 2 concurrent camera selectors were found, create 2 SingleCameraConfigs
// and compose them in a picture-in-picture layout.
val primary = SingleCameraConfig(
    cameraSelectorPrimary,
    useCaseGroup,
    CompositionSettings.Builder()
        .setAlpha(1.0f)
        .setOffset(0.0f, 0.25f)
        .setScale(0.5f, 0.5f)
        .build(),
    lifecycleOwner);
val secondary = SingleCameraConfig(
    cameraSelectorSecondary,
    useCaseGroup,
    CompositionSettings.Builder()
        .setAlpha(1.0f)
        .setOffset(0.5f, 0.25f)
        .setScale(0.5f, 0.5f)
        .build()
    lifecycleOwner);

// Bind to lifecycle
ConcurrentCamera concurrentCamera =
    cameraProvider.bindToLifecycle(listOf(primary, secondary));