Creating a column in KendoGrid that is not bound to datasource - kendo-ui

Question

I am using Kendo UI to bind a datasource to the Kendo Grid. I am trying to find the best way to create a column in the grid that is not bound to the datasource.
Currently, I am creating a field in the datasource and using some javascript and jQuery to set the values of that column after the data is read from the remote endpoint.
Datasource:
schema: {
model: {
fields: {
blah: {},
empty_column: {}
}
}
}
Grid:
columns: {
field: "empty_column",
width: 100,
title: "Empty"
}
Javascript:
datasource.data[item].set("empty_column", computed_value);
All code edited for brevity, it all works fine.
My question: is there a way to set the defaultValue for this new, empty column which is not connected to the remote endpoint?
When I set:
empty_column: {defaultValue: "None"}
the grid still displays 'undefined', I think because it is not receiveing any data for that field in the read operation. Is there a way to set the defaultValue in the grid? I haven't seen any examples of this...

Answer 1

defaultValue applies when you create a record, not when it is going to be displayed.
You can do:
Option 1: use parse in schema.fields.fieldName that would be something like this.
model: {
fields: {
empty_column: {
type : "string",
defaultValue: "none",
parse : function (data) {
if (!data.empty_columns) {
data.empty_column = "none";
}
return data;
}
},
blah : { type: "number" }
}
},
Option 2: Use schema.parse for adding the extra field value.
schema: {
model: {
fields: {
empty_column: {type: "string", defaultValue: "none"},
blah : { type: "number" }
}
},
parse: function (response) {
$.each(response, function (idx, item) {
if (!item.empty_column) {
item.empty_column = "none";
}
});
return response;
}
}
Of course, (for both options) if you certainly know that there is no previous value in empty_column you might save the test condition and leave only the assignment.