Add a BlogActivity that shows a list of blog posts

This commit lays the groundwork for #415

briar-android/src/org/briarproject/android/blogs/BlogPostAdapter.java

@@ -0,0 +1,153 @@
+package org.briarproject.android.blogs;
+
+import android.content.Context;
+import android.support.v7.util.SortedList;
+import android.support.v7.widget.RecyclerView;
+import android.text.format.DateUtils;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.TextView;
+
+import org.briarproject.R;
+import org.briarproject.util.StringUtils;
+
+import java.util.Collection;
+
+import static android.view.View.GONE;
+import static android.view.View.VISIBLE;
+
+class BlogPostAdapter extends
+		RecyclerView.Adapter<BlogPostAdapter.BlogPostHolder> {
+
+	private SortedList<BlogPostItem> posts = new SortedList<>(
+			BlogPostItem.class, new SortedList.Callback<BlogPostItem>() {
+
+		@Override
+		public int compare(BlogPostItem a, BlogPostItem b) {
+			if (a == b) return 0;
+			// The blog with the newest message comes first
+			long aTime = a.getTimestamp(), bTime = b.getTimestamp();
+			if (aTime > bTime) return -1;
+			if (aTime < bTime) return 1;
+			// Break ties by post title
+			if (a.getTitle() != null && b.getTitle() != null) {
+				return String.CASE_INSENSITIVE_ORDER
+						.compare(a.getTitle(), b.getTitle());
+			}
+			return 0;
+		}
+
+		@Override
+		public void onInserted(int position, int count) {
+			notifyItemRangeInserted(position, count);
+		}
+
+		@Override
+		public void onRemoved(int position, int count) {
+			notifyItemRangeRemoved(position, count);
+		}
+
+		@Override
+		public void onMoved(int fromPosition, int toPosition) {
+			notifyItemMoved(fromPosition, toPosition);
+		}
+
+		@Override
+		public void onChanged(int position, int count) {
+			notifyItemRangeChanged(position, count);
+		}
+
+		@Override
+		public boolean areContentsTheSame(BlogPostItem a, BlogPostItem b) {
+			return a.isRead() == b.isRead();
+		}
+
+		@Override
+		public boolean areItemsTheSame(BlogPostItem a, BlogPostItem b) {
+			return a.getId().equals(b.getId());
+		}
+	});
+
+	private final Context ctx;
+	private final String blogTitle;
+
+	BlogPostAdapter(Context ctx, String blogTitle) {
+		this.ctx = ctx;
+		this.blogTitle = blogTitle;
+	}
+
+	@Override
+	public BlogPostHolder onCreateViewHolder(ViewGroup parent, int viewType) {
+		View v = LayoutInflater.from(ctx).inflate(
+				R.layout.list_item_blog_post, parent, false);
+		return new BlogPostHolder(v);
+	}
+
+	@Override
+	public void onBindViewHolder(BlogPostHolder ui, int position) {
+		final BlogPostItem item = getItem(position);
+
+		// title
+		if (item.getTitle() != null) {
+			ui.title.setText(item.getTitle());
+			ui.title.setVisibility(VISIBLE);
+		} else {
+			ui.title.setVisibility(GONE);
+		}
+
+		// post body
+		ui.body.setText(StringUtils.fromUtf8(item.getBody()));
+
+		// date
+		ui.date.setText(
+				DateUtils.getRelativeTimeSpanString(ctx, item.getTimestamp()));
+
+		// new tag
+		if (item.isRead()) ui.unread.setVisibility(GONE);
+		else ui.unread.setVisibility(VISIBLE);
+	}
+
+	@Override
+	public int getItemCount() {
+		return posts.size();
+	}
+
+	public BlogPostItem getItem(int position) {
+		return posts.get(position);
+	}
+
+	public void addAll(Collection<BlogPostItem> items) {
+		posts.addAll(items);
+	}
+
+	public void remove(BlogPostItem item) {
+		posts.remove(item);
+	}
+
+	public void clear() {
+		posts.clear();
+	}
+
+	public boolean isEmpty() {
+		return posts.size() == 0;
+	}
+
+	static class BlogPostHolder extends RecyclerView.ViewHolder {
+		private final ViewGroup layout;
+		private final TextView title;
+		private final TextView unread;
+		private final TextView date;
+		private final TextView body;
+
+		BlogPostHolder(View v) {
+			super(v);
+
+			layout = (ViewGroup) v;
+			title = (TextView) v.findViewById(R.id.titleView);
+			unread = (TextView) v.findViewById(R.id.newView);
+			date = (TextView) v.findViewById(R.id.dateView);
+			body = (TextView) v.findViewById(R.id.bodyView);
+		}
+	}
+}