系统消息的tips中，没有内容就不显示“内容”

app/views/users/user_messages.html.erb

@@ -64,10 +64,8 @@
                 <% unless usm.subject.nil? %>
                     <p><strong>标题：</strong><%= usm.subject %></p>
                 <% end %>
-                <% if usm.description.nil? && usm.content.nil? %>
-
-                <% else %>
-                    <div class="fl"><strong>内容：</strong></div><div class="ml36"><%= usm.description.html_safe %></div>
+                <% if (!usm.description.nil? && usm.description != "") || (!usm.content.nil? && usm.content != "") %>
+                    <div class="fl"><strong>内容：</strong></div><div class="ml36"><%= usm.description.nil? ? usm.content.html_safe : usm.description.html_safe %></div>
                 <% end %>
               </div>
               <li class="homepageNewsTime fl"><%= time_tag(usm.created_at).html_safe %> </li>