Kendo UI TreeView: Add only nodes not exisisting in the view - kendo-ui

Question

I have tree view on a page which gets data from a ComboBox and a multiselect. The ComboBox contains the name of each ingredient and the multiselect contains the possible amount types which are then used as names for all their child nodes.
The tree looks something like that:
Ingredient 1
100mg
200mg
Ingredient 2
50mg
100mg
Everything works fine except I can add the same value twice because I am not able to validate if a node already exists.
Here is the function I am using to add new elements:
var addElement = function () {
var treeview = $("#ingredientTree").data("kendoTreeView");
var multiselect = $("#ingredientAmount").data("kendoMultiSelect");
var ingredientToAdd= $("#ingredient").val();
// I allways get an empty array at this point.
var exinstingIngredient= treeview.findByText(ingredientToAdd);
var children = new Array();
var amount = multiselect.value();
for (var j = 0; j < amount.length; j++) {
children.push({ text: amount[j] });
}
// it allways adds the items because the length is allways 0
if (exinstingIngredient.length === 0) {
treeview.append({
text: ingredientToAdd,
items: children
});
}
}
I don't understand why it can't find the existing element even I set its name as text and search for this text.
edit:
Here we have the treeview:
#(Html.Kendo().TreeView().TemplateId("treeview-template").Name("ingredientTree"))
That is the source of the ingredients, it handles just plain strings:
#(Html.Kendo().ComboBox()
.Name("ingredient")
.DataSource(source => source.Read(r => r.Url(Url.HttpRouteUrl("DefaultApi", new { controller = "InternationalIngredients" }))))
.Events(events => events.Change("onIngredientChanged"))
)
Following you find the source for amounts, which handles strings to:
#(Html.Kendo().MultiSelect()
.Name("ingredientAmount")
.DataSource(source => source.Read(read => read.Url(Url.HttpRouteUrl("DefaultApi", new { controller = "InternationalIngredientAmount" })).Data("getIngredient")).ServerFiltering(true)))
This is a function to determine the selected ingredient for the service call:
function getIngredient() {
return { ingredient: $("#ingredient").val() }
}

Answer 1

I've found the reason for my problem now. findByText seems to check the Content of the nodes span with class "k-in". Unfortunatly, this Content is modified when you add a template as described here. So if you want to find an element with template, you should use findById or you define your template in a way you can use jQuery.