[android] address review comments for displaying multiple images

briar-android/src/main/java/org/briarproject/briar/android/conversation/ConversationMessageViewHolder.java

@@ -33,8 +33,7 @@ class ConversationMessageViewHolder extends ConversationItemViewHolder {
 		// image list
 		RecyclerView list = v.findViewById(R.id.imageList);
 		list.setRecycledViewPool(imageViewPool);
-		adapter =
-				new ImageAdapter(v.getContext(), imageItemDecoration, listener);
+		adapter = new ImageAdapter(v.getContext(), listener);
 		list.setAdapter(adapter);
 		list.addItemDecoration(imageItemDecoration);
 

briar-android/src/main/java/org/briarproject/briar/android/conversation/ImageAdapter.java

@@ -19,36 +19,35 @@ import java.util.List;
 
 import static android.content.Context.WINDOW_SERVICE;
 import static java.util.Objects.requireNonNull;
+import static org.briarproject.briar.android.util.UiUtils.isRtl;
 
 @NotNullByDefault
 class ImageAdapter extends Adapter<ImageViewHolder> {
 
 	private final List<AttachmentItem> items = new ArrayList<>();
 	private final ConversationListener listener;
-	private final int imageSize, borderSize;
+	private final int imageSize;
 	private final int radiusBig, radiusSmall;
 	private final boolean isRtl;
 	@Nullable
 	private ConversationMessageItem conversationItem;
 
-	public ImageAdapter(Context ctx, ImageItemDecoration imageItemDecoration,
-			ConversationListener listener) {
+	ImageAdapter(Context ctx, ConversationListener listener) {
 		this.listener = listener;
-		borderSize = imageItemDecoration.getBorderSize();
 		imageSize = getImageSize(ctx);
 		Resources res = ctx.getResources();
 		radiusBig =
 				res.getDimensionPixelSize(R.dimen.message_bubble_radius_big);
 		radiusSmall =
 				res.getDimensionPixelSize(R.dimen.message_bubble_radius_small);
-		isRtl = imageItemDecoration.isRtl();
+		isRtl = isRtl(ctx);
 	}
 
 	@Override
 	public ImageViewHolder onCreateViewHolder(ViewGroup viewGroup, int type) {
 		View v = LayoutInflater.from(viewGroup.getContext()).inflate(
 				R.layout.list_item_image, viewGroup, false);
-		return new ImageViewHolder(v, imageSize, borderSize);
+		return new ImageViewHolder(v, imageSize);
 	}
 
 	@Override

briar-android/src/main/java/org/briarproject/briar/android/conversation/ImageItemDecoration.java

@@ -1,7 +1,6 @@
 package org.briarproject.briar.android.conversation;
 
 import android.content.Context;
-import android.content.res.Configuration;
 import android.content.res.Resources;
 import android.graphics.Rect;
 import android.support.v7.widget.RecyclerView;
@@ -11,9 +10,8 @@ import android.view.View;
 
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.briar.R;
+import org.briarproject.briar.android.util.UiUtils;
 
-import static android.os.Build.VERSION.SDK_INT;
-import static android.support.v4.view.ViewCompat.LAYOUT_DIRECTION_RTL;
 import static org.briarproject.briar.android.conversation.ImageAdapter.isBottomRow;
 import static org.briarproject.briar.android.conversation.ImageAdapter.isLeft;
 import static org.briarproject.briar.android.conversation.ImageAdapter.isTopRow;
@@ -22,24 +20,22 @@ import static org.briarproject.briar.android.conversation.ImageAdapter.singleInR
 @NotNullByDefault
 class ImageItemDecoration extends ItemDecoration {
 
-	private final int realBorderSize, border;
+	private final int border;
 	private final boolean isRtl;
 
-	public ImageItemDecoration(Context ctx) {
+	ImageItemDecoration(Context ctx) {
 		Resources res = ctx.getResources();
 
 		// for pixel perfection, add a pixel to the border if it has an odd size
 		int b = res.getDimensionPixelSize(R.dimen.message_bubble_border);
-		realBorderSize = b % 2 == 0 ? b : b + 1;;
+		int realBorderSize = b % 2 == 0 ? b : b + 1;
 
 		// we are applying half the border around the insides of each image
 		// to prevent differently sized images looking slightly broken
 		border = realBorderSize / 2;
 
 		// find out if we are showing a RTL language
-		Configuration config = res.getConfiguration();
-		isRtl = SDK_INT >= 17 &&
-				config.getLayoutDirection() == LAYOUT_DIRECTION_RTL;
+		isRtl = UiUtils.isRtl(ctx);
 	}
 
 	@Override
@@ -48,19 +44,11 @@ class ImageItemDecoration extends ItemDecoration {
 		if (state.getItemCount() == 1) return;
 		int pos = parent.getChildAdapterPosition(view);
 		int num = state.getItemCount();
-		boolean left = isLeft(pos) ^ isRtl;
+		boolean start = isLeft(pos) ^ isRtl;
 		outRect.top = isTopRow(pos) ? 0 : border;
-		outRect.left = left ? 0 : border;
-		outRect.right = left && !singleInRow(pos, num) ? border : 0;
+		outRect.left = start ? 0 : border;
+		outRect.right = start && !singleInRow(pos, num) ? border : 0;
 		outRect.bottom = isBottomRow(pos, num) ? 0 : border;
 	}
 
-	public int getBorderSize() {
-		return realBorderSize;
-	}
-
-	public boolean isRtl() {
-		return isRtl;
-	}
-
 }

briar-android/src/main/java/org/briarproject/briar/android/conversation/ImageViewHolder.java

@@ -25,13 +25,12 @@ class ImageViewHolder extends ViewHolder {
 	private static final int ERROR_RES = R.drawable.ic_image_broken;
 
 	protected final ImageView imageView;
-	private final int imageSize, borderSize;
+	private final int imageSize;
 
-	public ImageViewHolder(View v, int imageSize, int borderSize) {
+	ImageViewHolder(View v, int imageSize) {
 		super(v);
 		imageView = v.findViewById(R.id.imageView);
 		this.imageSize = imageSize;
-		this.borderSize = borderSize;
 	}
 
 	void bind(AttachmentItem attachment, Radii r, boolean single,
@@ -49,9 +48,7 @@ class ImageViewHolder extends ViewHolder {
 	private void setImageViewDimensions(AttachmentItem a, boolean single,
 			boolean needsStretch) {
 		LayoutParams params = (LayoutParams) imageView.getLayoutParams();
-		// actual image size will shrink half the border
-		int stretchSize = (imageSize - borderSize / 2) * 2 + borderSize;
-		int width = needsStretch ? stretchSize : imageSize;
+		int width = needsStretch ? imageSize * 2 : imageSize;
 		params.width = single ? a.getThumbnailWidth() : width;
 		params.height = single ? a.getThumbnailHeight() : imageSize;
 		params.setFullSpan(!single && needsStretch);

briar-android/src/main/java/org/briarproject/briar/android/conversation/ImageViewModel.java

@@ -48,10 +48,10 @@ public class ImageViewModel extends AndroidViewModel {
 	@IoExecutor
 	private final Executor ioExecutor;
 
-	private MutableLiveData<Boolean> saveState = new MutableLiveData<>();
+	private final MutableLiveData<Boolean> saveState = new MutableLiveData<>();
 
 	@Inject
-	public ImageViewModel(Application application,
+	ImageViewModel(Application application,
 			MessagingManager messagingManager,
 			@DatabaseExecutor Executor dbExecutor,
 			@IoExecutor Executor ioExecutor) {

briar-android/src/main/java/org/briarproject/briar/android/util/UiUtils.java

@@ -56,6 +56,7 @@ import static android.content.Intent.FLAG_ACTIVITY_NEW_TASK;
 import static android.os.Build.MANUFACTURER;
 import static android.os.Build.VERSION.SDK_INT;
 import static android.provider.Settings.ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS;
+import static android.support.v4.view.ViewCompat.LAYOUT_DIRECTION_RTL;
 import static android.support.v7.app.AppCompatDelegate.MODE_NIGHT_AUTO;
 import static android.support.v7.app.AppCompatDelegate.MODE_NIGHT_FOLLOW_SYSTEM;
 import static android.support.v7.app.AppCompatDelegate.MODE_NIGHT_NO;
@@ -354,4 +355,10 @@ public class UiUtils {
 		});
 	}
 
+	public static boolean isRtl(Context ctx) {
+		if (SDK_INT < 17) return false;
+		return ctx.getResources().getConfiguration().getLayoutDirection() ==
+				LAYOUT_DIRECTION_RTL;
+	}
+
 }