when I using branch dynamic loading, up button has no effect!

Hi expert, I’m developing filemanager backend webapp using java and now making listing direcrtory.
But when I getting the subdirectory list, there are so many strange things.

  1. when I click the send request for directory which is marked with webix_branch, the same branch request come (two times), But i don’t know why it happens.

  2. Although when I send request for some directory which is marked with webix_bracnch, as Documentation said, about that requests, I give response with JSONArray having “parent” and “data” (only two), That makes undefine directory on Webix file manager and normal clicked directory dosen’t show me its contents.
    I solve this problem by giving one more element named “id”.
    Though I give the correct value as PHP sample code and Document said, why this happen?

  3. Though I see and normal operation, when I click the up button, It can’t move its parent directory… why?

below is my JSON data sent to Webix fileManager.

/* this is root Directory */

[{
“size”:0,
“data”:[
{“date”:“1440421612”,“size”:0,“webix_branch”:“1”,“id”:"/a",“type”:“folder”,“value”:“a”,“webix_child_branch”:“1”},{“date”:“1440421612”,“size”:0,“webix_branch”:“1”,“id”:"/b",“type”:“folder”,“value”:“b”,“webix_child_branch”:“1”},{“date”:“1440421612”,“size”:0,“webix_branch”:“1”,“id”:"/c",“type”:“folder”,“value”:“c”},
{“date”:“1440421612”,“size”:0,“webix_branch”:“1”,“id”:"/d",“type”:“folder”,“value”:“d”},
{“date”:“1440421612”,“size”:0,“webix_branch”:“1”,“id”:"/e",“type”:“folder”,“value”:“e”},
{“date”:“1440421612”,“size”:11,“id”:"/file_g",“type”:“file”,“value”:“file_g”}
],
“id”:"/",
“type”:“folder”,
“value”:"/",
“open”:true
}]

/* end of root Directory */

/* this Directory is “/a”, for solving number 2, I added id field*/

[{
“parent”:"/a",
“data”:[
{“date”:“1440421612”,“size”:0,“webix_branch”:“1”,“id”:"/a/tdir03",“type”:“folder”,“value”:“tdir03”},
{“date”:“1440421612”,“size”:0,“webix_branch”:“1”,“id”:"/a/tdir2",“type”:“folder”,“value”:“tdir2”},
{“date”:“1440421612”,“size”:0,“webix_branch”:“1”,“id”:"/a/tdir4",“type”:“folder”,“value”:“tdir4”},
{“date”:“1440421612”,“size”:0,“webix_branch”:“1”,“id”:"/a/tdir5",“type”:“folder”,“value”:“tdir5”},
{“date”:“1440421612”,“size”:0,“webix_branch”:“1”,“id”:"/a/tdir6",“type”:“folder”,“value”:“tdir6”},
{“date”:“1440421612”,“size”:22,“id”:"/a/file02",“type”:“file”,“value”:“file02”}],
“id”:"/a"
}]

/* end of “/a” */

Note this. I never fix any front-end logic but only making back-end app with Java.

Thx

EDIT :
There is some thing is strange on html page about filemanager.
When I first load only root directory, subdirectory’s is makred as “webix_tree_branch2” (root is " webix_tree_branch1" but, after I load the any sub directory, it becomes “webix_tree_branch1” not “webix_tree_branch2”… I think that is problem. But I think I sent correct JSONArray, I don’t know why this happens.

EDIT: finally I solve the problem. That is my fault. I give the branch response as “JSONArray” not “JSONObject”. after change return about branch as JSONObject.
All thing is works! Thx!