GXT re-arrange data array index in TreeStore -

currently, i'm using gxt 3.0.6

i have treestore let's called "treestore", model data "parentdto".

private treestore<parentdto> treestore; treestore = new treestore<parentdto>(new modelkeyprovider<parentdto>(){               @override                public string getkey(parentdto item){                    return string.valueof(item.getparentid());                }           }); 

inside parentdto there list of childdto. if there parentdto data has list of childdto, want show in tree grid. use basic tree grid link https://www.sencha.com/examples/#exampleplace:basictreegrid

using reference, if try add 1 parentdto works fine, when problem when add many parent dto. here code adding data treestore

public void filltreestore(list<parentdto) listparent){    treestore.clear();    for(parentdto parentdto : listparent){       treestore.add(parentdto);       if(parentdto.getlistchild().size() > 0){         for(childdto childdto : parent.getlistchild()){             treestore.add(parentdto,childdto);         }        } } 

in case, need 1 level parent , child tree code enough. try debug code use expression

treestore.getall().get(index); 

when add 1 parentdto (parenta) has 1 child (childa). result be

treestore.getall().get(0) -> contain parenta treestore.getall().get(1) -> contain childa 

but if add 2 parentdto (parenta, parentb) , each of them have 1 child (childa,childb). result be

treestore.getall().get(0) -> contain parenta treestore.getall().get(1) -> contain parentb treestore.getall().get(2) -> contain childa treestore.getall().get(3) -> contain childb 

but in grid, data shown fine :

row 1 : parenta (this row can expand) row 2 : childa (the expanded row form parenta) row 3 : parentb (this row can expand) row 4 : childb (the expanded row form parentb) 

i need render icon if data "parent" use code :

(icon_variable).addbeforerendericoncelleventhandler(new beforerendericoncelleventhandler() {              @override             public void onbeforerendericoncell(beforerendericoncellevent event) {                 if(treestore.getparent(treestore.get(event.getselectedrowindex())) == null){                    //#render icon here                  }             }         }); 

the problem @ code

treestore.get(event.getselectedrowindex()) 

when parentb added trigger addbeforerendericoncelleventhandler method. event.getselectedrowindex() row index based on "grid's perspective". @ second row, grid's perspective (childa), event.getselectedrowindex() return 1. "treestore's perspective", index 1 "parentb", icon render messed up.

that's why, result need in treestore this

treestore.getall().get(0) -> contain parenta treestore.getall().get(1) -> contain childa treestore.getall().get(2) -> contain parentb treestore.getall().get(3) -> contain childb 

my solution : solve problem, now, use 2 stores, first 1 treestore, , second 1 liststore. each time parent , child added, insert them @ treestore , liststore. in liststore, keep parent's , child's index match grid's perspective, whenever addbeforerendericoncelleventhandler triggered, use liststore data.

in opinion, solution not enough because in case, maximum data can added store less 50, it's enough.

it looks default behavior. didn't trying guess can methods provide. i'm guessing trying traverse tree looking @ parent , of it's children before moving on next parent. it.

for (parentdto parent : treestore.getrootitems()){     (childdto child : treestore.getchildren(parent)){     } }