Add CameraXFlashToggleView and selfie flash.

res/drawable/camerax_flash_toggle.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto">
+    <item app:state_flash_auto="true" android:drawable="@drawable/flash_auto_32" />
+    <item app:state_flash_off="true" android:drawable="@drawable/flash_off_32" />
+    <item app:state_flash_on="true" android:drawable="@drawable/flash_on_32" />
+</selector>

res/layout/camera_controls_landscape.xml

@@ -17,6 +17,16 @@
         app:layout_constraintTop_toTopOf="parent"
         app:layout_constraintBottom_toBottomOf="parent"/>
 
+    <org.thoughtcrime.securesms.mediasend.camerax.CameraXFlashToggleView
+        android:id="@+id/camera_flash_button"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="14dp"
+        android:src="@drawable/camerax_flash_toggle"
+        app:layout_constraintStart_toEndOf="@+id/camera_flip_button"
+        app:layout_constraintTop_toTopOf="parent" />
+
     <ImageButton
         android:id="@+id/camera_flip_button"
         android:layout_width="wrap_content"
@@ -60,5 +70,16 @@
         app:layout_constraintEnd_toEndOf="@id/camera_capture_button"
         tools:visibility="visible" />
 
+    <View
+        android:id="@+id/camera_selfie_flash"
+        android:layout_width="0dp"
+        android:layout_height="0dp"
+        android:alpha="0"
+        app:layout_constraintTop_toTopOf="parent"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        android:background="@color/white" />
+
 </androidx.constraintlayout.widget.ConstraintLayout>
 

res/layout/camera_controls_portrait.xml

@@ -17,6 +17,16 @@
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent" />
 
+    <org.thoughtcrime.securesms.mediasend.camerax.CameraXFlashToggleView
+        android:id="@+id/camera_flash_button"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="14dp"
+        android:layout_marginEnd="16dp"
+        android:src="@drawable/camerax_flash_toggle"
+        app:layout_constraintEnd_toStartOf="@+id/camera_flip_button"
+        app:layout_constraintTop_toTopOf="parent" />
+
     <ImageButton
         android:id="@+id/camera_flip_button"
         android:layout_width="wrap_content"
@@ -61,5 +71,16 @@
         app:layout_constraintEnd_toEndOf="parent"
         tools:visibility="visible" />
 
+    <View
+        android:id="@+id/camera_selfie_flash"
+        android:layout_width="0dp"
+        android:layout_height="0dp"
+        android:alpha="0"
+        app:layout_constraintTop_toTopOf="parent"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        android:background="@color/white" />
+
 </androidx.constraintlayout.widget.ConstraintLayout>
 

res/values/attrs.xml

@@ -362,4 +362,10 @@
             <enum name="top" value="1" />
         </attr>
     </declare-styleable>
+
+    <declare-styleable name="CameraXFlashState">
+        <attr name="state_flash_auto" format="boolean" />
+        <attr name="state_flash_off" format="boolean" />
+        <attr name="state_flash_on" format="boolean" />
+    </declare-styleable>
 </resources>

src/org/thoughtcrime/securesms/mediasend/CameraXFragment.java

@@ -29,6 +29,7 @@ import com.bumptech.glide.Glide;
 
 import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.logging.Log;
+import org.thoughtcrime.securesms.mediasend.camerax.CameraXFlashToggleView;
 import org.thoughtcrime.securesms.mediasend.camerax.CameraXUtil;
 import org.thoughtcrime.securesms.mediasend.camerax.CameraXView;
 import org.thoughtcrime.securesms.mms.DecryptableStreamUriLoader.DecryptableUri;
@@ -52,6 +53,7 @@ public class CameraXFragment extends Fragment implements CameraFragment {
   private ViewGroup          controlsContainer;
   private Controller         controller;
   private MediaSendViewModel viewModel;
+  private View               selfieFlash;
 
   public static CameraXFragment newInstance() {
     return new CameraXFragment();
@@ -160,14 +162,18 @@ public class CameraXFragment extends Fragment implements CameraFragment {
 
   @SuppressLint({"ClickableViewAccessibility", "MissingPermission"})
   private void initControls() {
-    View flipButton    = requireView().findViewById(R.id.camera_flip_button);
-    View captureButton = requireView().findViewById(R.id.camera_capture_button);
-    View galleryButton = requireView().findViewById(R.id.camera_gallery_button);
-    View countButton   = requireView().findViewById(R.id.camera_count_button);
+    View                   flipButton    = requireView().findViewById(R.id.camera_flip_button);
+    View                   captureButton = requireView().findViewById(R.id.camera_capture_button);
+    View                   galleryButton = requireView().findViewById(R.id.camera_gallery_button);
+    View                   countButton   = requireView().findViewById(R.id.camera_count_button);
+    CameraXFlashToggleView flashButton   = requireView().findViewById(R.id.camera_flash_button);
+
+    selfieFlash = requireView().findViewById(R.id.camera_selfie_flash);
 
     captureButton.setOnClickListener(v -> {
       captureButton.setEnabled(false);
       flipButton.setEnabled(false);
+      flashButton.setEnabled(false);
       onCaptureClicked();
     });
 
@@ -181,6 +187,8 @@ public class CameraXFragment extends Fragment implements CameraFragment {
         animation.setDuration(200);
         animation.setInterpolator(new DecelerateInterpolator());
         flipButton.startAnimation(animation);
+        flashButton.setAutoFlashEnabled(camera.hasFlash());
+        flashButton.setFlash(camera.getFlash());
       });
 
       GestureDetector gestureDetector = new GestureDetector(requireContext(), new GestureDetector.SimpleOnGestureListener() {
@@ -199,6 +207,10 @@ public class CameraXFragment extends Fragment implements CameraFragment {
       flipButton.setVisibility(View.GONE);
     }
 
+    flashButton.setAutoFlashEnabled(camera.hasFlash());
+    flashButton.setFlash(camera.getFlash());
+    flashButton.setOnFlashModeChangedListener(camera::setFlash);
+
     galleryButton.setOnClickListener(v -> controller.onGalleryClicked());
     countButton.setOnClickListener(v -> controller.onCameraCountButtonClicked());
 
@@ -208,9 +220,17 @@ public class CameraXFragment extends Fragment implements CameraFragment {
   private void onCaptureClicked() {
     Stopwatch stopwatch = new Stopwatch("Capture");
 
+    CameraXSelfieFlashHelper flashHelper = new CameraXSelfieFlashHelper(
+        requireActivity().getWindow(),
+        camera,
+        selfieFlash
+    );
+
     camera.takePicture(new ImageCapture.OnImageCapturedListener() {
       @Override
       public void onCaptureSuccess(ImageProxy image, int rotationDegrees) {
+        flashHelper.endFlash();
+
         SimpleTask.run(CameraXFragment.this.getLifecycle(), () -> {
           stopwatch.split("captured");
           try {
@@ -234,8 +254,11 @@ public class CameraXFragment extends Fragment implements CameraFragment {
 
       @Override
       public void onError(ImageCapture.UseCaseError useCaseError, String message, @Nullable Throwable cause) {
+        flashHelper.endFlash();
         controller.onCameraError();
       }
     });
+
+    flashHelper.startFlash();
   }
 }

src/org/thoughtcrime/securesms/mediasend/CameraXSelfieFlashHelper.java

@@ -0,0 +1,72 @@
+package org.thoughtcrime.securesms.mediasend;
+
+import android.view.View;
+import android.view.Window;
+import android.view.WindowManager;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.RequiresApi;
+import androidx.camera.core.CameraX;
+import androidx.camera.core.FlashMode;
+
+import org.thoughtcrime.securesms.mediasend.camerax.CameraXView;
+
+@RequiresApi(21)
+final class CameraXSelfieFlashHelper {
+
+  private static final float MAX_SCREEN_BRIGHTNESS    = 1f;
+  private static final float MAX_SELFIE_FLASH_ALPHA   = 0.75f;
+  private static final long  SELFIE_FLASH_DURATION_MS = 250;
+
+  private final Window      window;
+  private final CameraXView camera;
+  private final View        selfieFlash;
+
+  private float   brightnessBeforeFlash;
+  private boolean inFlash;
+
+  CameraXSelfieFlashHelper(@NonNull Window window,
+                           @NonNull CameraXView camera,
+                           @NonNull View selfieFlash)
+  {
+    this.window      = window;
+    this.camera      = camera;
+    this.selfieFlash = selfieFlash;
+  }
+
+  void startFlash() {
+    if (inFlash || !shouldUseViewBasedFlash()) return;
+    inFlash = true;
+
+    WindowManager.LayoutParams params = window.getAttributes();
+
+    brightnessBeforeFlash   = params.screenBrightness;
+    params.screenBrightness = MAX_SCREEN_BRIGHTNESS;
+    window.setAttributes(params);
+
+    selfieFlash.animate()
+               .alpha(MAX_SELFIE_FLASH_ALPHA)
+               .setDuration(SELFIE_FLASH_DURATION_MS);
+  }
+
+  void endFlash() {
+    if (!inFlash) return;
+
+    WindowManager.LayoutParams params = window.getAttributes();
+
+    params.screenBrightness = brightnessBeforeFlash;
+    window.setAttributes(params);
+
+    selfieFlash.animate()
+               .alpha(0f)
+               .setDuration(SELFIE_FLASH_DURATION_MS);
+
+    inFlash = false;
+  }
+
+  private boolean shouldUseViewBasedFlash() {
+    return camera.getFlash() == FlashMode.ON &&
+           !camera.hasFlash()                &&
+           camera.getCameraLensFacing() == CameraX.LensFacing.FRONT;
+  }
+}

src/org/thoughtcrime/securesms/mediasend/camerax/CameraXFlashToggleView.java

@@ -0,0 +1,131 @@
+package org.thoughtcrime.securesms.mediasend.camerax;
+
+import android.content.Context;
+import android.os.Bundle;
+import android.os.Parcelable;
+import android.util.AttributeSet;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.appcompat.widget.AppCompatImageView;
+import androidx.camera.core.FlashMode;
+
+import org.thoughtcrime.securesms.R;
+
+import java.util.Arrays;
+import java.util.List;
+
+public final class CameraXFlashToggleView extends AppCompatImageView {
+
+  private static final String STATE_FLASH_INDEX  = "flash.toggle.state.flash.index";
+  private static final String STATE_SUPPORT_AUTO = "flash.toggle.state.support.auto";
+  private static final String STATE_PARENT       = "flash.toggle.state.parent";
+
+  private static final int[]           FLASH_AUTO     = { R.attr.state_flash_auto         };
+  private static final int[]           FLASH_OFF      = { R.attr.state_flash_off          };
+  private static final int[]           FLASH_ON       = { R.attr.state_flash_on           };
+  private static final int[][]         FLASH_ENUM     = { FLASH_AUTO, FLASH_OFF, FLASH_ON };
+  private static final List<FlashMode> FLASH_MODES    = Arrays.asList(FlashMode.AUTO, FlashMode.OFF, FlashMode.ON);
+  private static final FlashMode       FLASH_FALLBACK = FlashMode.OFF;
+
+  private boolean                    supportsFlashModeAuto = true;
+  private int                        flashIndex;
+  private OnFlashModeChangedListener flashModeChangedListener;
+
+  public CameraXFlashToggleView(Context context) {
+    this(context, null);
+  }
+
+  public CameraXFlashToggleView(Context context, @Nullable AttributeSet attrs) {
+    this(context, attrs, 0);
+  }
+
+  public CameraXFlashToggleView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
+    super(context, attrs, defStyleAttr);
+
+    super.setOnClickListener((v) -> setFlash(FLASH_MODES.get((flashIndex + 1) % FLASH_ENUM.length)));
+  }
+
+  @Override
+  public int[] onCreateDrawableState(int extraSpace) {
+    final int[] extra         = FLASH_ENUM[flashIndex];
+    final int[] drawableState = super.onCreateDrawableState(extraSpace + extra.length);
+    mergeDrawableStates(drawableState, extra);
+    return drawableState;
+  }
+
+  @Override
+  public void setOnClickListener(@Nullable OnClickListener l) {
+    throw new IllegalStateException("This View does not support custom click listeners.");
+  }
+
+  public void setAutoFlashEnabled(boolean isAutoEnabled) {
+    supportsFlashModeAuto = isAutoEnabled;
+    setFlash(FLASH_MODES.get(flashIndex));
+  }
+
+  public void setFlash(@NonNull FlashMode flashMode) {
+    flashIndex = resolveFlashIndex(FLASH_MODES.indexOf(flashMode), supportsFlashModeAuto);
+    refreshDrawableState();
+    notifyListener();
+  }
+
+  public void setOnFlashModeChangedListener(@Nullable OnFlashModeChangedListener listener) {
+    this.flashModeChangedListener = listener;
+  }
+
+  @Override
+  protected Parcelable onSaveInstanceState() {
+    Parcelable parentState = super.onSaveInstanceState();
+    Bundle     bundle      = new Bundle();
+
+    bundle.putParcelable(STATE_PARENT, parentState);
+    bundle.putInt(STATE_FLASH_INDEX, flashIndex);
+    bundle.putBoolean(STATE_SUPPORT_AUTO, supportsFlashModeAuto);
+    return bundle;
+  }
+
+  @Override
+  protected void onRestoreInstanceState(Parcelable state) {
+    if (state instanceof Bundle) {
+      Bundle savedState = (Bundle) state;
+
+      supportsFlashModeAuto = savedState.getBoolean(STATE_SUPPORT_AUTO);
+      setFlash(FLASH_MODES.get(
+          resolveFlashIndex(savedState.getInt(STATE_FLASH_INDEX), supportsFlashModeAuto))
+      );
+
+      super.onRestoreInstanceState(savedState.getParcelable(STATE_PARENT));
+    } else {
+      super.onRestoreInstanceState(state);
+    }
+  }
+
+  private void notifyListener() {
+    if (flashModeChangedListener == null) return;
+
+    flashModeChangedListener.flashModeChanged(FLASH_MODES.get(flashIndex));
+  }
+
+  private static int resolveFlashIndex(int desiredFlashIndex, boolean supportsFlashModeAuto) {
+    if (isIllegalFlashIndex(desiredFlashIndex)) {
+      throw new IllegalArgumentException("Unsupported index: " + desiredFlashIndex);
+    }
+    if (isUnsupportedFlashMode(desiredFlashIndex, supportsFlashModeAuto)) {
+      return FLASH_MODES.indexOf(FLASH_FALLBACK);
+    }
+    return desiredFlashIndex;
+  }
+
+  private static boolean isIllegalFlashIndex(int desiredFlashIndex) {
+    return desiredFlashIndex < 0 || desiredFlashIndex > FLASH_ENUM.length;
+  }
+
+  private static boolean isUnsupportedFlashMode(int desiredFlashIndex, boolean supportsFlashModeAuto) {
+    return FLASH_MODES.get(desiredFlashIndex) == FlashMode.AUTO && !supportsFlashModeAuto;
+  }
+
+  public interface OnFlashModeChangedListener {
+    void flashModeChanged(FlashMode flashMode);
+  }
+}

src/org/thoughtcrime/securesms/mediasend/camerax/CameraXModule.java

@@ -686,6 +686,16 @@ final class CameraXModule {
     mImageCapture.setFlashMode(flash);
   }
 
+  public boolean hasFlash() {
+    try {
+      Boolean flashInfoAvailable = mCameraManager.getCameraCharacteristics(getActiveCamera())
+                                                 .get(CameraCharacteristics.FLASH_INFO_AVAILABLE);
+      return flashInfoAvailable == Boolean.TRUE;
+    } catch (CameraInfoUnavailableException | CameraAccessException e) {
+      return false;
+    }
+  }
+
   public void enableTorch(boolean torch) {
     if (mPreview == null) {
       return;

src/org/thoughtcrime/securesms/mediasend/camerax/CameraXView.java

@@ -683,6 +683,10 @@ public final class CameraXView extends ViewGroup {
     mCameraModule.setFlash(flashMode);
   }
 
+  public boolean hasFlash() {
+    return mCameraModule.hasFlash();
+  }
+
   private int getRelativeCameraOrientation(boolean compensateForMirroring) {
     return mCameraModule.getRelativeCameraOrientation(compensateForMirroring);
   }