In the SharePoint 2013 list view web part, the paging, filtering and sorting functionality is driven by the inplview.js file. This is supported by AJAX calls against a RESTful service inplview.aspx. I am able to extend the JavaScript inplview object to implement client side refresh as data is updated on the server.

To configure the automatic refresh by OOTB (out-of-the-box) configuration, go to the Web Part Properties: 

What I find unattractive of this approach is that it is using the older AJAX UpdatePanel introduced in ASP .NET 2.0.

• There is at least 23kb transferred for each refresh which is a relatively heavier in bandwidth.
  
• The http response time is longer.
  
• Using IE 8 browser, there is a memory leak such that memory utilization by the browser maxes out.
• The out of the paging, filtering and sorting with the AJAX options do not work well together. For example, the AJAX refresh option sometimes shows no rows even after repeated combination of filtering and manual OOTB AJAX refresh. To resolve, refresh the page without any query string parameters.

The applicable business scenario or requirement is when frequently added and updated list items by multiple users are to be seen updated in the browser without user requiring to manually refresh the page. 

In SharePoint 2013, when the user interacts with the list view web part for activities such as paging, column filtering and sorting, there is an AJAX request making a RESTful call to inplview.aspx.
 Compared to the OOTB refresh, the inplview.aspx REST calls are significantly lighter in bandwidth and has faster response time.

How inplview.js Works

The javascript code that supports the list view web part paging, sorting and filtering is in the inplview.js file

The sequence of calls are made as follows:

1. Browser
   1. User clicks on list view web part to page, sort and filter
   2. invoke objects in various SharePoint .js files
   3. invoke objects inplview.js
2. Server
   1. inplview.aspx that is a RESTful http service
   2. HTTP response back to browser with only JSON formatted row data.

Using the chrome JavaScript debugger against inplview.js, I have identified the following sequence of function calls. To support the refresh, I have “forked” the code with my own custom functions.

The Implementation

There is no explicit data refresh support in the inplview javascript code so I have injected custom code that extends the inplview javascript object to have supporting functions to implement refresh.

// automatic refresh based on interval
function autoRefresh()
{
 window.setInterval(listViewRefresh, 2000); // 20 seconds
}

// refresh all list view web parts on the page
function listViewRefresh() {
 $('#lblMessage').text('refreshed ').fadeIn("slow").fadeOut("slow"); // debugging
 inplview.MyRestoreAllClvpsNavigation = MyRestoreAllClvpsNavigation;
 inplview.MyRestoreAllClvpsNavigation();
}

// Enumerate list view web parts
function MyRestoreAllClvpsNavigation()
{
 EnumCLVPs(MyCLVPRestoreNavigation);
}

// refresh referencing list view web part
function MyCLVPRestoreNavigation(clvp) {
 var strHash = ajaxNavigate.getParam("InplviewHash" + clvp.WebPartId());
 if (strHash == null)
 strHash = '';

 var strInpl = '?' + DecodeHashAsQueryString(strHash);
 var strShowInGrid = GetUrlKeyValue("ShowInGrid", true, strInpl);

 if (strShowInGrid == "True") {
 InitGridFromView(clvp.ctx.view, true);
 }
 else if (clvp.ctx.inGridMode) {
 ExitGrid(clvp.ctx.view, true);
 }
 clvp.strHash = strHash;
 clvp.fRestore = true;
 var curRootFolder = GetRootFolder2(this);

 if (curRootFolder != null)
 strInpl = SetUrlKeyValue("RootFolder", unescapeProperly(curRootFolder), true, strInpl);
 clvp.RefreshPagingEx(strInpl, true, null);

 }

$(document).ready(function() {
 autoRefresh();
});

Benefits

1. Overcome IE8 browser memory leak issue
2. Noticeable performance improvement over OOTB Ajax option
3. The ability to extend and customize the client side rendering of the list view web part functionality

Caveats

1. Upgrades and patches:
   Since this is extending from product JavaScript code, in the event of upgrades or patching, there could breaking changes.
   To mitigate this risk, remember to regression test after a product upgrade and patch.

Supportability

1. Still supports general list view paging, column filtering and sorting.
2. Exception: column filtering and sorting is not supported on lookup columns as it is already with OOTB.
3. Ability to refresh all list view web parts that exist on the same page.

I’ll have a another blog post to add filtering based on user input by customizing the inpvliew.js