total

Get the total number of data items in the underlying data. This properties is initially undefined and is set to a numerical value after a read().

var dataSource = new shield.DataSource({
    remote: {
        read: {
            url: "/content/xml/movies.xml"
        }
    }
});

console.log(dataSource.total);      //undefined
dataSource.read(function () {
    console.log(dataSource.total);  //some number
});