Wire functionality to show Postview and Processing Progress Indicator

- if the device supports process indicator then show process indicator
- if the device supports postview then show the postview

Test: manually tested using S24

CameraXExtensions/app/src/main/java/com/example/android/cameraxextensions/MainActivity.kt

@@ -24,7 +24,11 @@ import androidx.activity.result.contract.ActivityResultContracts
 import androidx.appcompat.app.AppCompatActivity
 import androidx.camera.extensions.ExtensionMode
 import androidx.core.app.ActivityCompat
-import androidx.lifecycle.*
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.lifecycleScope
+import androidx.lifecycle.repeatOnLifecycle
 import com.example.android.cameraxextensions.adapter.CameraExtensionItem
 import com.example.android.cameraxextensions.model.CameraState
 import com.example.android.cameraxextensions.model.CameraUiAction
@@ -203,9 +207,10 @@ class MainActivity : AppCompatActivity() {
                                     } else {
                                         PostCaptureScreenViewState.PostCaptureScreenHiddenViewState
                                     }
-                                }
-                                .updateCameraScreen {
+                                }.updateCameraScreen {
                                     it.hideCameraControls()
+                                        .hideProcessProgressViewState()
+                                        .hidePostview()
                                 }
                         )
                     }
@@ -220,6 +225,24 @@ class MainActivity : AppCompatActivity() {
                                     it.showCameraControls()
                                         .enableCameraShutter(true)
                                         .enableSwitchLens(true)
+                                        .hideProcessProgressViewState()
+                                        .hidePostview()
+                                }
+                        )
+                    }
+                    is CaptureState.CapturePostview -> {
+                        captureScreenViewState.emit(
+                            captureScreenViewState.value
+                                .updateCameraScreen {
+                                    it.showPostview(state.bitmap)
+                                }
+                        )
+                    }
+                    is CaptureState.CaptureProcessProgress -> {
+                        captureScreenViewState.emit(
+                            captureScreenViewState.value
+                                .updateCameraScreen {
+                                    it.showProcessProgressViewState(state.progress)
                                 }
                         )
                     }

CameraXExtensions/app/src/main/java/com/example/android/cameraxextensions/model/CameraUiState.kt

@@ -16,6 +16,7 @@
 
 package com.example.android.cameraxextensions.model
 
+import android.graphics.Bitmap
 import androidx.camera.core.CameraSelector.LENS_FACING_BACK
 import androidx.camera.core.CameraSelector.LensFacing
 import androidx.camera.core.ImageCapture
@@ -74,6 +75,16 @@ sealed class CaptureState {
      */
     object CaptureStarted : CaptureState()
 
+    /**
+     * Capture postview is ready
+     */
+    data class CapturePostview(val bitmap: Bitmap): CaptureState()
+
+    /**
+     * Capture process progress updated with the [progress] value
+     */
+    data class CaptureProcessProgress(val progress: Int): CaptureState()
+
     /**
      * Capture completed successfully.
      */

CameraXExtensions/app/src/main/java/com/example/android/cameraxextensions/viewmodel/CameraExtensionsViewModel.kt

@@ -17,13 +17,13 @@
 package com.example.android.cameraxextensions.viewmodel
 
 import android.app.Application
+import android.graphics.Bitmap
 import androidx.camera.core.*
 import androidx.camera.core.CameraSelector.LensFacing
 import androidx.camera.extensions.ExtensionMode
 import androidx.camera.extensions.ExtensionsManager
 import androidx.camera.lifecycle.ProcessCameraProvider
 import androidx.camera.view.PreviewView
-import androidx.compose.ui.layout.ScaleFactor
 import androidx.core.net.toUri
 import androidx.lifecycle.LifecycleOwner
 import androidx.lifecycle.ViewModel
@@ -58,7 +58,7 @@ class CameraExtensionsViewModel(
 
     private var camera: Camera? = null
 
-    private val imageCapture = ImageCapture.Builder()
+    private var imageCapture = ImageCapture.Builder()
         .setTargetAspectRatio(AspectRatio.RATIO_16_9)
         .build()
 
@@ -142,6 +142,19 @@ class CameraExtensionsViewModel(
                 currentCameraUiState.extensionMode
             )
         }
+
+        cameraProvider.unbindAll()
+        camera = cameraProvider.bindToLifecycle(lifecycleOwner, cameraSelector)
+
+        camera?.cameraInfo?.let {
+            val isPostviewSupported =
+                ImageCapture.getImageCaptureCapabilities(it).isPostviewSupported
+            imageCapture = ImageCapture.Builder()
+                .setTargetAspectRatio(AspectRatio.RATIO_16_9)
+                .setPostviewEnabled(isPostviewSupported)
+                .build()
+        }
+
         val useCaseGroup = UseCaseGroup.Builder()
             .setViewPort(previewView.viewPort!!)
             .addUseCase(imageCapture)
@@ -223,6 +236,14 @@ class CameraExtensionsViewModel(
                 .setMetadata(metadata)
                 .build()
 
+        camera?.cameraInfo?.let {
+            if (ImageCapture.getImageCaptureCapabilities(it).isCaptureProcessProgressSupported) {
+                viewModelScope.launch {
+                    _captureUiState.emit(CaptureState.CaptureProcessProgress(0))
+                }
+            }
+        }
+
         imageCapture.takePicture(
             outputFileOptions,
             Dispatchers.Default.asExecutor(),
@@ -242,6 +263,18 @@ class CameraExtensionsViewModel(
                         _captureUiState.emit(CaptureState.CaptureFailed(exception))
                     }
                 }
+
+                override fun onCaptureProcessProgressed(progress: Int) {
+                    viewModelScope.launch {
+                        _captureUiState.emit(CaptureState.CaptureProcessProgress(progress))
+                    }
+                }
+
+                override fun onPostviewBitmapAvailable(bitmap: Bitmap) {
+                    viewModelScope.launch {
+                        _captureUiState.emit(CaptureState.CapturePostview(bitmap))
+                    }
+                }
             })
     }
 

CameraXExtensions/app/src/main/java/com/example/android/cameraxextensions/viewstate/CameraPreviewScreenViewState.kt

@@ -16,6 +16,7 @@
 
 package com.example.android.cameraxextensions.viewstate
 
+import android.graphics.Bitmap
 import com.example.android.cameraxextensions.adapter.CameraExtensionItem
 
 /**
@@ -25,7 +26,9 @@ import com.example.android.cameraxextensions.adapter.CameraExtensionItem
 data class CameraPreviewScreenViewState(
     val shutterButtonViewState: ShutterButtonViewState = ShutterButtonViewState(),
     val switchLensButtonViewState: SwitchLensButtonViewState = SwitchLensButtonViewState(),
-    val extensionsSelectorViewState: CameraExtensionSelectorViewState = CameraExtensionSelectorViewState()
+    val extensionsSelectorViewState: CameraExtensionSelectorViewState = CameraExtensionSelectorViewState(),
+    val processProgressViewState: ProcessProgressIndicatorViewState = ProcessProgressIndicatorViewState(),
+    val postviewViewState: PostviewViewState = PostviewViewState()
 ) {
     fun hideCameraControls(): CameraPreviewScreenViewState =
         copy(
@@ -49,6 +52,17 @@ data class CameraPreviewScreenViewState(
 
     fun setAvailableExtensions(extensions: List<CameraExtensionItem>): CameraPreviewScreenViewState =
         copy(extensionsSelectorViewState = extensionsSelectorViewState.copy(extensions = extensions))
+
+    fun showPostview(bitmap: Bitmap): CameraPreviewScreenViewState =
+        copy(postviewViewState = PostviewViewState(isVisible = true, bitmap = bitmap))
+
+    fun hidePostview(): CameraPreviewScreenViewState = copy(postviewViewState = PostviewViewState())
+
+    fun showProcessProgressViewState(progress: Int): CameraPreviewScreenViewState =
+        copy(processProgressViewState = ProcessProgressIndicatorViewState(isVisible = true, progress = progress))
+
+    fun hideProcessProgressViewState(): CameraPreviewScreenViewState =
+        copy(processProgressViewState = ProcessProgressIndicatorViewState())
 }
 
 data class CameraExtensionSelectorViewState(
@@ -64,4 +78,14 @@ data class ShutterButtonViewState(
 data class SwitchLensButtonViewState(
     val isVisible: Boolean = false,
     val isEnabled: Boolean = false
-)
+)
+
+data class ProcessProgressIndicatorViewState(
+    val isVisible: Boolean = false,
+    val progress: Int = 0
+)
+
+data class PostviewViewState(
+    val isVisible: Boolean = false,
+    val bitmap: Bitmap? = null
+)