Use HttpProxy and TreeLoader has error,how to solve the problem?thanks

[tang9528]

  try {
      ModelType type = new ModelType();
      type.root = "fileInfo";
      type.addField("name");
      type.addField("size");
      HttpProxy proxy = new HttpProxy(new RequestBuilder(RequestBuilder.GET,"tree.js"));
      TreeLoader loader = new BaseTreeLoader(proxy, new JsonReader(type));
      TreeStore store = new TreeStore(loader);//if not this,it's ok
      loader.load();
   }catch(Exception error){
      Log.warn("error:" + error.getMessage());//Log source from com.allen_sauer.gwt.log.client.Log
   } 

tree.js
{"fileInfo":[{"name": "\u6d4b\u8bd5.doc","size": 1024}, {"name": "dbhelper.html","size": 1024}, {"name": "a+p+m","size": 0}, {"name": "\u4f60\u597d.pptx","size": 1034}]} 

however have such error

Uncaught Exception: java.lang.RuntimeException: java.lang.ClassCastException Caused by: java.lang.ClassCastException: null 

how to solve the problem?




thanks

[tang9528]

i find

Jsonreader.java

public ListLoadResult read(C loadConfig, Object data)

TreeStore.java

protected void onLoad(TreeLoadEvent le) {
   .....
   for (M model : (List<M>) le.data)
   .....
}

le.data is ListLoadResult not List<M> lead the error.

so,i extend the JsonReader.java

 public ArrayList<ModelData> read(C loadConfig, Object data)

Demo has realize

1)rails providing json data
2)tree node dynamic loading

detail please access attachments.