Fix Camera Switching Bug

packages/camera/camera/example/android/app/build.gradle

@@ -26,6 +26,14 @@ android {
     namespace 'io.flutter.plugins.cameraexample'
     compileSdk flutter.compileSdkVersion
 
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_17
+        targetCompatibility JavaVersion.VERSION_17
+    }
+
+    kotlinOptions {
+        jvmTarget = JavaVersion.VERSION_17.toString()
+    }
 
     defaultConfig {
         applicationId "io.flutter.plugins.cameraexample"

packages/camera/camera_android_camerax/android/src/main/java/io/flutter/plugins/camerax/CameraInfoHostApiImpl.java

@@ -42,6 +42,17 @@ public Long getSensorRotationDegrees(@NonNull Long identifier) {
     return Long.valueOf(cameraInfo.getSensorRotationDegrees());
   }
 
+  /**
+   * Returns the lens facing of the {@link androidx.camera.core.Camera} that is
+   * represented by the {@link CameraInfo} with the specified identifier.
+   */
+  @Override
+  @NonNull
+  public Long getLensFacing(@NonNull Long identifier) {
+    CameraInfo cameraInfo =
+            (CameraInfo) Objects.requireNonNull(instanceManager.getInstance(identifier));
+    return Long.valueOf(cameraInfo.getLensFacing());
+
   /**
    * Retrieves the {@link LiveData} of the {@link CameraState} that is tied to the {@link
    * androidx.camera.core.Camera} that is represented by the {@link CameraInfo} with the specified

packages/camera/camera_android_camerax/lib/src/android_camera_camerax.dart

@@ -262,25 +262,26 @@ class AndroidCameraCameraX extends CameraPlatform {
         await processCameraProvider!.getAvailableCameraInfos();
 
     CameraLensDirection? cameraLensDirection;
+    int? cameraLensDirectionNum;
     int cameraCount = 0;
     int? cameraSensorOrientation;
     String? cameraName;
 
     for (final CameraInfo cameraInfo in cameraInfos) {
+
+      cameraLensDirectionNum = await cameraInfo.getLensFacing();
       // Determine the lens direction by filtering the CameraInfo
       // TODO(gmackall): replace this with call to CameraInfo.getLensFacing when changes containing that method are available
-      if ((await proxy
-              .createCameraSelector(CameraSelector.lensFacingBack)
-              .filter(<CameraInfo>[cameraInfo]))
-          .isNotEmpty) {
+
+      // CameraSelector.LENS_FACING_FRONT;
+
+      if (cameraLensDirectionNum == 1) {
         cameraLensDirection = CameraLensDirection.back;
-      } else if ((await proxy
-              .createCameraSelector(CameraSelector.lensFacingFront)
-              .filter(<CameraInfo>[cameraInfo]))
-          .isNotEmpty) {
+      }
+      else if (cameraLensDirectionNum == 0) {
         cameraLensDirection = CameraLensDirection.front;
-      } else {
-        //Skip this CameraInfo as its lens direction is unknown
+      }
+      else {
         continue;
       }
 

packages/camera/camera_android_camerax/lib/src/camera_info.dart

@@ -38,6 +38,10 @@ class CameraInfo extends JavaObject {
   Future<int> getSensorRotationDegrees() =>
       _api.getSensorRotationDegreesFromInstance(this);
 
+  /// Gets lens facing of the camera.
+  Future<int> getLensFacing() =>
+      _api.getLensFacingFromInstance(this);
+
   /// Starts listening for the camera closing.
   Future<LiveData<CameraState>> getCameraState() =>
       _api.getCameraStateFromInstance(this);
@@ -71,6 +75,14 @@ class _CameraInfoHostApiImpl extends CameraInfoHostApi {
     return sensorRotationDegrees;
   }
 
+  /// Gets the lens facing of the specified [CameraInfo] instance.
+  Future<int> getLensFacingFromInstance(
+      CameraInfo instance,
+      ) async {
+    final int lensFacing = await getLensFacing(instanceManager.getIdentifier(instance)!);
+    return lensFacing;
+  }
+
   /// Gets the [LiveData<CameraState>] that represents the state of the camera
   /// to which the CameraInfo [instance] pertains.
   Future<LiveData<CameraState>> getCameraStateFromInstance(