Question

The first time rendering a template works fine. It displays as expected:

When navigating back and navigating to the same screen again, results in the following, where it loses the list formatting:

Why does this happen and how can it be prevented?

Below is the template definition:

<div data-role="view" data-layout="app" data-title="Time Card" id="screen1">
</div>
<script type="text/x-kendo-template" id="template1">
    Heading
    <ul data-role="listview" data-style="inset" data-type="group"> 
        <ul data-role="listview">
            Group 1
            # for (var i = 0; i < data.headers.length; i++) { #
                <li><a>#= data.heades[i].Item #</a></li>
            # } #
        </ul>
        <ul data-role="listview">
            Group 2
            <li>hello</li>
            <li>goodbye</li>
        </ul>
    </ul>
</script>

Below is the code that fills the template and navigates to it:

var templateContent = $("#template1").html();
var template = kendo.template(templateContent);
var data = {headers: headers};
$("#screen1").html(template(data));
app.navigate("#screen1");

Answer 1

This is happening because you are replacing the HTML of the View which is not supported. For example the widgets will not be re-initialised after the change.

$("#screen1").html(template(data)); //html replacement of the View's content is not supported

My recommendation is to bind the widget to a DataSource and use its the API methods to change the content. ListView will automatically re-render the template after data change.