fixed get_bulletins_json of gprs bug

vendor/built_in_modules/announcement/app/controllers/panel/announcement/back_end/bulletins_controller.rb

@@ -35,11 +35,20 @@ class Panel::Announcement::BackEnd::BulletinsController < OrbitBackendController
       else
         deadline = I18n.t("no_deadline")
       end
-      @data[I18n.t("category")][b.bulletin_category.title] = { title: b.title,
+      if @data[I18n.t("category")][b.bulletin_category.title].nil?
+         @data[I18n.t("category")][b.bulletin_category.title] = Array.new
+         @data[I18n.t("category")][b.bulletin_category.title] << { title: b.title,
                                            postdate: display_date_time(b.postdate),
                                            deadline: deadline,
                                            tag: b.sorted_tags.to_a,
-      }
+         }
+      else
+         @data[I18n.t("category")][b.bulletin_category.title] << { title: b.title,
+                                           postdate: display_date_time(b.postdate),
+                                           deadline: deadline,
+                                           tag: b.sorted_tags.to_a,
+         }
+      end
     end
     render :json => @data.to_json
   end