Update ViewModel

Author: MagicalMeghan

samples/camera/camerax/src/main/java/com/example/platform/camerax/basic/CameraXBasic.kt

@@ -35,7 +35,6 @@ import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.offset
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
-import androidx.compose.foundation.layout.wrapContentSize
 import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.filled.ArrowBack
@@ -86,7 +85,7 @@ fun CameraXBasic(modifier: Modifier = Modifier) {
     var showCapturedImage by remember { mutableStateOf<Uri?>(null) }
     val cameraPermissionState = rememberPermissionState(Manifest.permission.CAMERA)
     val imageCaptureCallbackExecutor: ExecutorService = remember { Executors.newSingleThreadExecutor() }
-    val viewModel = remember { CameraXBasicViewModel() }
+    val viewModel = viewModel { CameraXBasicViewModel() }
 
     DisposableEffect(Unit) {
         onDispose {

samples/camera/camerax/src/main/java/com/example/platform/camerax/basic/CameraXBasicViewModel.kt

@@ -37,6 +37,7 @@ import androidx.camera.lifecycle.awaitInstance
 import androidx.compose.ui.geometry.Offset
 import androidx.core.content.ContextCompat
 import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.ViewModel
 import kotlinx.coroutines.awaitCancellation
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
@@ -52,7 +53,7 @@ import java.util.concurrent.ExecutorService
  * functionality using CameraX. It exposes a [StateFlow] for the camera preview [SurfaceRequest]
  * to be used in a composable.
  */
-class CameraXBasicViewModel {
+class CameraXBasicViewModel : ViewModel() {
     private val _surfaceRequest = MutableStateFlow<SurfaceRequest?>(null)
     val surfaceRequest: StateFlow<SurfaceRequest?> = _surfaceRequest
     private var surfaceMeteringPointFactory: SurfaceOrientedMeteringPointFactory? = null