Fix announcement page error.

app/controllers/admin/announcements_controller.rb

@@ -244,7 +244,7 @@ class Admin::AnnouncementsController < OrbitAdminController
     bulletin.save
     build_email(bulletin,I18n.locale)
     create_feed_cache(bulletin)
-    redirect_to params['referer_url']
+    redirect_to admin_announcements_path
   end
 
   def approve_bulletin
@@ -324,19 +324,19 @@ class Admin::AnnouncementsController < OrbitAdminController
     now_bulletin_page = Bulletin.where(:title.ne => "",:is_preview.in=>[false,nil])
                               .order_by(sort).map(&:id).map.with_index.select{|v,i| v==bulletin.id}[0][1] rescue nil
     now_bulletin_page = now_bulletin_page.nil? ? 0 : ((now_bulletin_page+1).to_f/10).ceil
-    redirect_to "/zh_tw/admin/announcements?page=#{now_bulletin_page}"
+    redirect_to admin_announcements_path(:page=>now_bulletin_page)
   end
 
   def destroy
     @bulletin.destroy
-    redirect_to "/admin/announcements"
+    redirect_to admin_announcements_path
   end
 
   def delete
     if params[:ids]
       Bulletin.any_in(:uid => params[:ids]).destroy_all
     end
-    redirect_to "/admin/announcements"
+    redirect_to admin_announcements_path
   end
 
   def preview