How does the DataSource.Transport.Read property populate the datasource when Read is set as a function

[Jacques]

In the example below, taken from the Kendo site, how does the dataSource itself get populated? 

var dataSource = new kendo.data.DataSource({
  transport: {
    read: function(options) {
      // make JSONP request to http://demos.kendoui.com/service/products
      $.ajax({
        url: "http://demos.kendoui.com/service/products",
        dataType: "jsonp", // "jsonp" is required for cross-domain requests; use "json" for same-domain requests
        success: function(result) {
          // notify the data source that the request succeeded
          options.success(result);
        },
        error: function(result) {
          // notify the data source that the request failed
          options.error(result);
        }
      });
    }
  }
});
dataSource.fetch(function() {
  console.log(dataSource.view().length); // displays "77"
});

Nothing in this example seems to indicate how the data source would get populate if the ajax call succeeds? 

[Atanas Korchev]

Hi Jacques,

 Perhaps you've missed the following code:

        success: function(result) {

          // notify the data source that the request succeeded

          options.success(result);

        }

As the comment says calling the success function notifies the data source that the ajax request has succeeded.

Regards,
Atanas Korchev
Telerik

[Jacques]

Hi Atanas, 

"As the comment says calling the success function notifies the data source that the ajax request has succeeded."

Sure it says that it "notifies" the data source that the ajax request succeeded, but do we then assume that options.success(result) is also passing the resulting data to the dataSource? Notifying and populating data seem like two different things, but if you say that the success method/function does exactly that, then I'm happy? 

Thanks for the answer.

[Saranya]

I have implemented this and am successfully reading and setting the results on success. However, this is causing the transport read method to trigger again. What would cause this?

When I set a break point and follow the stack trace it shows that options.success(result); is triggering the read function call to generate another ajax request.

I do not have any dataBound, binding, etc. events initialized.

In the demo Set Read as a Function, I cannot replicate the issue
http://docs.telerik.com/kendo-ui/api/javascript/data/datasource#configuration-transport.read

[Boyan Dimitrov]

Hello Saranya,

I already replied in one of your support threads that we are not aware of such problem. We would need a sample dojo example which replicates this problem in order to perform investigation. 

Regards,
Boyan Dimitrov
Telerik by Progress