[camerax] Wrap Android classes/methods required to set the exposure mode

packages/camera/camera_android_camerax/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.5.0+31
+
+* Wraps CameraX classes needed to set capture request options, which is needed to implement setting the exposure mode.
+
 ## 0.5.0+30
 
 * Adds documentation to clarify how the plugin uses resolution presets as target resolutions for CameraX.

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

@@ -22,7 +22,7 @@ public class AnalyzerHostApiImpl implements AnalyzerHostApi {
   private final InstanceManager instanceManager;
   private final AnalyzerProxy proxy;
 
-  /** Proxy for constructors and static method of {@link ImageAnalysis.Analyzer}. */
+  /** Proxy for constructor of {@link ImageAnalysis.Analyzer}. */
   @VisibleForTesting
   public static class AnalyzerProxy {
 
@@ -95,7 +95,7 @@ public AnalyzerHostApiImpl(
    *
    * @param binaryMessenger used to communicate with Dart over asynchronous messages
    * @param instanceManager maintains instances stored to communicate with attached Dart objects
-   * @param proxy proxy for constructors and static method of {@link ImageAnalysis.Analyzer}
+   * @param proxy proxy for constructor of {@link ImageAnalysis.Analyzer}
    */
   @VisibleForTesting
   AnalyzerHostApiImpl(

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

@@ -19,7 +19,7 @@ public class AspectRatioStrategyHostApiImpl implements AspectRatioStrategyHostAp
   private final InstanceManager instanceManager;
   private final AspectRatioStrategyProxy proxy;
 
-  /** Proxy for constructors and static method of {@link AspectRatioStrategy}. */
+  /** Proxy for constructor of {@link AspectRatioStrategy}. */
   @VisibleForTesting
   public static class AspectRatioStrategyProxy {
     /** Creates an instance of {@link AspectRatioStrategy}. */
@@ -43,7 +43,7 @@ public AspectRatioStrategyHostApiImpl(@NonNull InstanceManager instanceManager)
    * Constructs an {@link AspectRatioStrategyHostApiImpl}.
    *
    * @param instanceManager maintains instances stored to communicate with attached Dart objects
-   * @param proxy proxy for constructors and static method of {@link AspectRatioStrategy}
+   * @param proxy proxy for constructor of {@link AspectRatioStrategy}
    */
   @VisibleForTesting
   AspectRatioStrategyHostApiImpl(

packages/camera/camera_android_camerax/android/src/main/java/io/flutter/plugins/camerax/Camera2CameraControlHostApiImpl.java

@@ -0,0 +1,140 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package io.flutter.plugins.camerax;
+
+import android.content.Context;
+import androidx.annotation.NonNull;
+import androidx.annotation.OptIn;
+import androidx.annotation.VisibleForTesting;
+import androidx.camera.camera2.interop.Camera2CameraControl;
+import androidx.camera.camera2.interop.CaptureRequestOptions;
+import androidx.camera.core.CameraControl;
+import androidx.core.content.ContextCompat;
+import com.google.common.util.concurrent.FutureCallback;
+import com.google.common.util.concurrent.Futures;
+import com.google.common.util.concurrent.ListenableFuture;
+import io.flutter.plugins.camerax.GeneratedCameraXLibrary.Camera2CameraControlHostApi;
+import java.util.Objects;
+
+/**
+ * Host API implementation for {@link Camera2CameraControl}.
+ *
+ * <p>This class may handle instantiating and adding native object instances that are attached to a
+ * Dart instance or handle method calls on the associated native class or an instance of the class.
+ */
+public class Camera2CameraControlHostApiImpl implements Camera2CameraControlHostApi {
+  private final InstanceManager instanceManager;
+  private final Camera2CameraControlProxy proxy;
+
+  /** Proxy for constructor and methods of {@link Camera2CameraControl}. */
+  @VisibleForTesting
+  public static class Camera2CameraControlProxy {
+    Context context;
+
+    /**
+     * Creates an instance of {@link Camera2CameraControl} derived from specified {@link
+     * CameraControl} instance.
+     */
+    @OptIn(markerClass = androidx.camera.camera2.interop.ExperimentalCamera2Interop.class)
+    public @NonNull Camera2CameraControl create(@NonNull CameraControl cameraControl) {
+      return Camera2CameraControl.from(cameraControl);
+    }
+
+    /**
+     * Adds a {@link CaptureRequestOptions} to update the capture session with the options it
+     * contains.
+     */
+    @OptIn(markerClass = androidx.camera.camera2.interop.ExperimentalCamera2Interop.class)
+    public void addCaptureRequestOptions(
+        @NonNull Camera2CameraControl camera2CameraControl,
+        @NonNull CaptureRequestOptions bundle,
+        @NonNull GeneratedCameraXLibrary.Result<Void> result) {
+      if (context == null) {
+        throw new IllegalStateException("Context must be set to add capture request options.");
+      }
+
+      ListenableFuture<Void> addCaptureRequestOptionsFuture =
+          camera2CameraControl.addCaptureRequestOptions(bundle);
+
+      Futures.addCallback(
+          addCaptureRequestOptionsFuture,
+          new FutureCallback<Void>() {
+            public void onSuccess(Void voidResult) {
+              result.success(null);
+            }
+
+            public void onFailure(Throwable t) {
+              result.error(t);
+            }
+          },
+          ContextCompat.getMainExecutor(context));
+    }
+  }
+
+  /**
+   * Constructs a {@link Camera2CameraControlHostApiImpl}.
+   *
+   * @param instanceManager maintains instances stored to communicate with attached Dart objects
+   * @param context {@link Context} used to retrieve {@code Executor}
+   */
+  public Camera2CameraControlHostApiImpl(
+      @NonNull InstanceManager instanceManager, @NonNull Context context) {
+    this(instanceManager, new Camera2CameraControlProxy(), context);
+  }
+
+  /**
+   * Constructs a {@link Camera2CameraControlHostApiImpl}.
+   *
+   * @param instanceManager maintains instances stored to communicate with attached Dart objects
+   * @param proxy proxy for constructor and methods of {@link Camera2CameraControl}
+   * @param context {@link Context} used to retrieve {@code Executor}
+   */
+  @VisibleForTesting
+  Camera2CameraControlHostApiImpl(
+      @NonNull InstanceManager instanceManager,
+      @NonNull Camera2CameraControlProxy proxy,
+      @NonNull Context context) {
+    this.instanceManager = instanceManager;
+    this.proxy = proxy;
+    proxy.context = context;
+  }
+
+  /**
+   * Sets the context that the {@code Camera2CameraControl} will use to listen for the result of
+   * setting capture request options.
+   *
+   * <p>If using the camera plugin in an add-to-app context, ensure that this is called anytime that
+   * the context changes.
+   */
+  public void setContext(@NonNull Context context) {
+    this.proxy.context = context;
+  }
+
+  @Override
+  public void create(@NonNull Long identifier, @NonNull Long cameraControlIdentifier) {
+    instanceManager.addDartCreatedInstance(
+        proxy.create(Objects.requireNonNull(instanceManager.getInstance(cameraControlIdentifier))),
+        identifier);
+  }
+
+  @Override
+  public void addCaptureRequestOptions(
+      @NonNull Long identifier,
+      @NonNull Long captureRequestOptionsIdentifier,
+      @NonNull GeneratedCameraXLibrary.Result<Void> result) {
+    proxy.addCaptureRequestOptions(
+        getCamera2CameraControlInstance(identifier),
+        Objects.requireNonNull(instanceManager.getInstance(captureRequestOptionsIdentifier)),
+        result);
+  }
+
+  /**
+   * Retrieves the {@link Camera2CameraControl} instance associated with the specified {@code
+   * identifier}.
+   */
+  private Camera2CameraControl getCamera2CameraControlInstance(@NonNull Long identifier) {
+    return Objects.requireNonNull(instanceManager.getInstance(identifier));
+  }
+}

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

@@ -29,7 +29,7 @@ public class CameraControlHostApiImpl implements CameraControlHostApi {
   private final InstanceManager instanceManager;
   private final CameraControlProxy proxy;
 
-  /** Proxy for constructors and static method of {@link CameraControl}. */
+  /** Proxy for methods of {@link CameraControl}. */
   @VisibleForTesting
   public static class CameraControlProxy {
     Context context;
@@ -99,6 +99,10 @@ public void startFocusAndMetering(
         @NonNull CameraControl cameraControl,
         @NonNull FocusMeteringAction focusMeteringAction,
         @NonNull GeneratedCameraXLibrary.Result<Long> result) {
+      if (context == null) {
+        throw new IllegalStateException("Context must be set to set zoom ratio.");
+      }
+
       ListenableFuture<FocusMeteringResult> focusMeteringResultFuture =
           cameraControl.startFocusAndMetering(focusMeteringAction);
 
@@ -173,6 +177,7 @@ public void onFailure(Throwable t) {
    * Constructs an {@link CameraControlHostApiImpl}.
    *
    * @param instanceManager maintains instances stored to communicate with attached Dart objects
+   * @param context {@link Context} used to retrieve {@code Executor}
    */
   public CameraControlHostApiImpl(
       @NonNull BinaryMessenger binaryMessenger,
@@ -185,8 +190,8 @@ public CameraControlHostApiImpl(
    * Constructs an {@link CameraControlHostApiImpl}.
    *
    * @param instanceManager maintains instances stored to communicate with attached Dart objects
-   * @param proxy proxy for constructors and static method of {@link CameraControl}
-   * @param context {@link Context} used to retrieve {@code Executor} used to enable torch mode
+   * @param proxy proxy for methods of {@link CameraControl}
+   * @param context {@link Context} used to retrieve {@code Executor}
    */
   @VisibleForTesting
   CameraControlHostApiImpl(
@@ -203,11 +208,11 @@ public CameraControlHostApiImpl(
   }
 
   /**
-   * Sets the context that the {@code ProcessCameraProvider} will use to enable/disable torch mode
-   * and set the zoom ratio.
+   * Sets the context that the {@code CameraControl} will use to enable/disable torch mode and set
+   * the zoom ratio.
    *
-   * <p>If using the camera plugin in an add-to-app context, ensure that a new instance of the
-   * {@code CameraControl} is fetched via {@code #enableTorch} anytime the context changes.
+   * <p>If using the camera plugin in an add-to-app context, ensure that this is called anytime that
+   * the context changes.
    */
   public void setContext(@NonNull Context context) {
     this.proxy.context = context;

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

@@ -0,0 +1,118 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package io.flutter.plugins.camerax;
+
+import android.hardware.camera2.CaptureRequest;
+import androidx.annotation.NonNull;
+import androidx.annotation.OptIn;
+import androidx.annotation.VisibleForTesting;
+import androidx.camera.camera2.interop.CaptureRequestOptions;
+import io.flutter.plugins.camerax.GeneratedCameraXLibrary.CaptureRequestKeySupportedType;
+import io.flutter.plugins.camerax.GeneratedCameraXLibrary.CaptureRequestOptionsHostApi;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Host API implementation for {@link CaptureRequestOptions}.
+ *
+ * <p>This class may handle instantiating and adding native object instances that are attached to a
+ * Dart instance or handle method calls on the associated native class or an instance of the class.
+ */
+public class CaptureRequestOptionsHostApiImpl implements CaptureRequestOptionsHostApi {
+  private final InstanceManager instanceManager;
+  private final CaptureRequestOptionsProxy proxy;
+
+  /** Proxy for constructor of {@link CaptureRequestOptions}. */
+  @VisibleForTesting
+  public static class CaptureRequestOptionsProxy {
+    /** Creates an instance of {@link CaptureRequestOptions}. */
+    // Suppression is safe because the type shared between the key and value pairs that
+    // represent capture request options is checked on the Dart side.
+    @SuppressWarnings("unchecked")
+    @OptIn(markerClass = androidx.camera.camera2.interop.ExperimentalCamera2Interop.class)
+    public @NonNull CaptureRequestOptions create(
+        @NonNull Map<CaptureRequestKeySupportedType, Object> options) {
+      CaptureRequestOptions.Builder builder = getCaptureRequestOptionsBuilder();
+
+      for (Map.Entry<CaptureRequestKeySupportedType, Object> option : options.entrySet()) {
+        CaptureRequestKeySupportedType optionKeyType = option.getKey();
+        CaptureRequest.Key<? extends Object> optionKey = getCaptureRequestKey(optionKeyType);
+        Object optionValue = option.getValue();
+
+        if (optionValue == null) {
+          builder.clearCaptureRequestOption(optionKey);
+          continue;
+        }
+
+        switch (optionKeyType) {
+          case CONTROL_AE_LOCK:
+            builder.setCaptureRequestOption(
+                (CaptureRequest.Key<Boolean>) optionKey, (Boolean) optionValue);
+            break;
+          default:
+            throw new IllegalArgumentException(
+                "The capture request key "
+                    + optionKeyType.toString()
+                    + "is not currently supported by the plugin.");
+        }
+      }
+
+      return builder.build();
+    }
+
+    private CaptureRequest.Key<? extends Object> getCaptureRequestKey(
+        CaptureRequestKeySupportedType type) {
+      CaptureRequest.Key<? extends Object> key;
+      switch (type) {
+        case CONTROL_AE_LOCK:
+          key = CaptureRequest.CONTROL_AE_LOCK;
+          break;
+        default:
+          throw new IllegalArgumentException(
+              "The capture request key is not currently supported by the plugin.");
+      }
+      return key;
+    }
+
+    @VisibleForTesting
+    @OptIn(markerClass = androidx.camera.camera2.interop.ExperimentalCamera2Interop.class)
+    public @NonNull CaptureRequestOptions.Builder getCaptureRequestOptionsBuilder() {
+      return new CaptureRequestOptions.Builder();
+    }
+  }
+
+  /**
+   * Constructs a {@link CaptureRequestOptionsHostApiImpl}.
+   *
+   * @param instanceManager maintains instances stored to communicate with attached Dart objects
+   */
+  public CaptureRequestOptionsHostApiImpl(@NonNull InstanceManager instanceManager) {
+    this(instanceManager, new CaptureRequestOptionsProxy());
+  }
+
+  /**
+   * Constructs a {@link CaptureRequestOptionsHostApiImpl}.
+   *
+   * @param instanceManager maintains instances stored to communicate with attached Dart objects
+   * @param proxy proxy for constructor of {@link CaptureRequestOptions}
+   */
+  @VisibleForTesting
+  CaptureRequestOptionsHostApiImpl(
+      @NonNull InstanceManager instanceManager, @NonNull CaptureRequestOptionsProxy proxy) {
+    this.instanceManager = instanceManager;
+    this.proxy = proxy;
+  }
+
+  @Override
+  public void create(@NonNull Long identifier, @NonNull Map<Long, Object> options) {
+    Map<CaptureRequestKeySupportedType, Object> decodedOptions =
+        new HashMap<CaptureRequestKeySupportedType, Object>();
+    for (Map.Entry<Long, Object> option : options.entrySet()) {
+      decodedOptions.put(
+          CaptureRequestKeySupportedType.values()[option.getKey().intValue()], option.getValue());
+    }
+    instanceManager.addDartCreatedInstance(proxy.create(decodedOptions), identifier);
+  }
+}

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

@@ -23,7 +23,7 @@ public class FallbackStrategyHostApiImpl implements FallbackStrategyHostApi {
 
   private final FallbackStrategyProxy proxy;
 
-  /** Proxy for constructors and static method of {@link FallbackStrategy}. */
+  /** Proxy for constructor of {@link FallbackStrategy}. */
   @VisibleForTesting
   public static class FallbackStrategyProxy {
     /** Creates an instance of {@link FallbackStrategy}. */
@@ -59,7 +59,7 @@ public FallbackStrategyHostApiImpl(@NonNull InstanceManager instanceManager) {
    * Constructs a {@link FallbackStrategyHostApiImpl}.
    *
    * @param instanceManager maintains instances stored to communicate with attached Dart objects
-   * @param proxy proxy for constructors and static method of {@link FallbackStrategy}
+   * @param proxy proxy for constructor of {@link FallbackStrategy}
    */
   FallbackStrategyHostApiImpl(
       @NonNull InstanceManager instanceManager, @NonNull FallbackStrategyProxy proxy) {

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

@@ -24,7 +24,7 @@ public class FocusMeteringActionHostApiImpl implements FocusMeteringActionHostAp
 
   private final FocusMeteringActionProxy proxy;
 
-  /** Proxy for constructors and static method of {@link FocusMeteringAction}. */
+  /** Proxy for constructor of {@link FocusMeteringAction}. */
   @VisibleForTesting
   public static class FocusMeteringActionProxy {
     /** Creates an instance of {@link FocusMeteringAction}. */
@@ -90,7 +90,7 @@ public FocusMeteringActionHostApiImpl(@NonNull InstanceManager instanceManager)
    * Constructs a {@link FocusMeteringActionHostApiImpl}.
    *
    * @param instanceManager maintains instances stored to communicate with attached Dart objects
-   * @param proxy proxy for constructors and static method of {@link FocusMeteringAction}
+   * @param proxy proxy for constructor of {@link FocusMeteringAction}
    */
   FocusMeteringActionHostApiImpl(
       @NonNull InstanceManager instanceManager, @NonNull FocusMeteringActionProxy proxy) {