Dojo Tree Refresh - dojo

Question

Using Dojo 1.3, after adding a child (i.e. folder or item) to a tree, is there a way to have it reflected immediately via refresh or some other method?

Answer 1

From the official Dojo manual
Updating a Tree
People often ask:
how do I update a tree (adding or
deleting items?)
You can't update the
tree directly, but rather you need to
update the model. Usually the model is
connected to a data store and in that
case you need to update the data
store. Thus, you need to use a data
store that allows updates (through
it's official API), like
dojo.data.ItemFileWriteStore.
how do I refresh a Tree from the
store?
This isn't supported. The store
needs to notify the tree of any
changes to the data. Currently this is
really only supported (out of the box)
by dojo.data.ItemFileWriteStore, as
setting up a client-server dojo.data
source where the server notifies the
client whenever the data has changed
is quite complicated, and beyond the
scope of dojo, which is a client-only
solution.

Answer 2

Say, if your model has the query `{type:'continent'} - meaning any items with this property are top-level-items, then the following will model extension will monitor changes and refresh the tree's view
var dataStore = new ItemFileWriteStore( { ... });
new Tree({
store: dataStore,
model: new ForestModel({
onNewItem: function(item, parentInfo){
if(this.store.getValue(item, 'type') == 'continent'){
this._requeryTop();
}
this.inherited(arguments);
}
}
});
This should in turn call childrenChanged in the tree and update it every time a new item is added.
See model reference
As an addition, if the item added is not a toplevel item, an immediate update should be doable with this statement. parent is the treenode which has had an item added to its children.
tree._collapseNode(parent);
parent.state = 'UNCHECKED';
tree._expandNode(parent);
A more or less 'standard' refresh of the tree can be achieved by following. Reason for it not being added to base implementation, i think is because it will break the linkage with DnD features on a tree
dojo.declare("My.Tree", [dijit.Tree], {
// Close the store? (So that the store will do a new fetch()).
reloadStoreOnRefresh : true,
update: function() {
this.model.store.clearOnClose = this.reloadStoreOnRefresh;
this.model.store.close();
// Completely delete every node from the dijit.Tree
delete this._itemNodesMap;
this._itemNodesMap = {};
this.rootNode.state = "UNCHECKED";
delete this.model.root.children;
this.model.root.children = null;
// Destroy the widget
this.rootNode.destroyRecursive();
// Recreate the model, (with the model again)
this.model.constructor(this.model)
// Rebuild the tree
this.postMixInProperties();
this._load();
}
}
);

Answer 3

I've solved this WITHOUT needing the refresh.
_refreshNodeMapping: function (newNodeData) {
if(!this._itemNodesMap[newNodeData.identity]) return;
var nodeMapToRefresh = this._itemNodesMap[newNodeData.identity][0].item;
var domNode = this._itemNodesMap[newNodeData.identity][0].domNode;
//For every updated value, reset the old ones
for(var val in newNodeData)
{
nodeMapToRefresh[val] = newNodeData[val];
if(val == 'label')
{
domNode.innerHTML = newNodeData[val];
}
}
}