Add CameraPreviewManager and CameraPreviewView for camera functionality

android/app/src/main/java/com/lynkeduppro/icamera/CameraPreviewManager.kt

@@ -0,0 +1,39 @@
+package com.lynkeduppro.camera
+
+import com.facebook.react.uimanager.SimpleViewManager
+import com.facebook.react.uimanager.ThemedReactContext
+import com.facebook.react.uimanager.annotations.ReactProp
+import com.facebook.react.bridge.LifecycleEventListener
+
+class CameraPreviewManager :
+    SimpleViewManager<CameraPreviewView>(),
+    LifecycleEventListener {
+
+    private var previewView: CameraPreviewView? = null
+
+    override fun getName(): String = "CameraPreviewView"
+
+    override fun createViewInstance(reactContext: ThemedReactContext): CameraPreviewView {
+        previewView = CameraPreviewView(reactContext)
+        reactContext.addLifecycleEventListener(this)
+        return previewView!!
+    }
+
+    @ReactProp(name = "active")
+    fun setActive(view: CameraPreviewView, active: Boolean) {
+        if (active && reactContext is androidx.lifecycle.LifecycleOwner) {
+            view.startCamera(reactContext as androidx.lifecycle.LifecycleOwner)
+        }
+    }
+
+    override fun onHostResume() {
+        previewView?.let {
+            if (reactContext is androidx.lifecycle.LifecycleOwner) {
+                it.startCamera(reactContext as androidx.lifecycle.LifecycleOwner)
+            }
+        }
+    }
+
+    override fun onHostPause() {}
+    override fun onHostDestroy() {}
+}

android/app/src/main/java/com/lynkeduppro/icamera/CameraPreviewView.kt

@@ -0,0 +1,33 @@
+package com.lynkeduppro.camera
+
+import android.content.Context
+import androidx.camera.core.CameraSelector
+import androidx.camera.core.Preview
+import androidx.camera.lifecycle.ProcessCameraProvider
+import androidx.camera.view.PreviewView
+import androidx.core.content.ContextCompat
+import androidx.lifecycle.LifecycleOwner
+
+class CameraPreviewView(context: Context) : PreviewView(context) {
+
+    fun startCamera(lifecycleOwner: LifecycleOwner) {
+        val cameraProviderFuture = ProcessCameraProvider.getInstance(context)
+
+        cameraProviderFuture.addListener({
+            val cameraProvider = cameraProviderFuture.get()
+
+            val preview = Preview.Builder().build().also {
+                it.setSurfaceProvider(surfaceProvider)
+            }
+
+            val cameraSelector = CameraSelector.DEFAULT_BACK_CAMERA
+
+            cameraProvider.unbindAll()
+            cameraProvider.bindToLifecycle(
+                lifecycleOwner,
+                cameraSelector,
+                preview
+            )
+        }, ContextCompat.getMainExecutor(context))
+    }
+}