新增错误提示

src/main/java/com/yutou/qqbot/models/setu/GetSeTu.java

@@ -51,6 +51,12 @@ public class GetSeTu extends Model {
                             super.onDownload(file);
                             QQBotManager.getInstance().sendMessage(file, qq, "");
                         }
+
+                        @Override
+                        public void onError(Exception e) {
+                            super.onError(e);
+                            QQBotManager.getInstance().sendMessage(qq,"获取失败");
+                        }
                     });
         }
     }