Show Blog Invitations

This refactors the forum invitation code,
so it can be used by both: forums and blogs.

briar-android/src/org/briarproject/android/sharing/ForumInvitationAdapter.java

@@ -0,0 +1,31 @@
+package org.briarproject.android.sharing;
+
+import android.content.Context;
+
+import org.briarproject.api.forum.Forum;
+
+class ForumInvitationAdapter extends InvitationAdapter {
+
+	ForumInvitationAdapter(Context ctx, AvailableForumClickListener listener) {
+		super(ctx, listener);
+	}
+
+	@Override
+	public void onBindViewHolder(InvitationsViewHolder ui, int position) {
+		super.onBindViewHolder(ui, position);
+		InvitationItem item = getItem(position);
+		Forum forum = (Forum) item.getShareable();
+
+		ui.avatar.setText(forum.getName().substring(0, 1));
+		ui.avatar.setBackgroundBytes(item.getShareable().getId().getBytes());
+
+		ui.name.setText(forum.getName());
+	}
+
+	int compareInvitations(InvitationItem o1, InvitationItem o2) {
+		return String.CASE_INSENSITIVE_ORDER
+				.compare(((Forum) o1.getShareable()).getName(),
+						((Forum) o2.getShareable()).getName());
+	}
+
+}