JSON Data Loader

Data is a Client Side JSON prefetcher, that makes it easy to provide JSON data that is available at render time. The data can also be loaded via Widget.load() at a later time. There is optionally also a callback available on load.

The list elements below are rendered with JavaScript using preloaded data:

Load via Widget Call

data.xhtml

Documentation


<!-- JavaScript method that can render movie titles as li tags -->
<script>
    function renderMovies(movies) {
        for (var i = 0; i < movies.length; i++) {
            var movie = movies[i];
            var li = document.createElement('li');
            li.appendChild(document.createTextNode(movie.title));
            document.getElementById('movieList').appendChild(li);
        }
    }
</script>

<!-- Preload movie data and render via JS method, avoids AJAX-call -->
<t:data value="#{controller.movies}" var="movies" success="renderMovies" />

<!-- Lazy load data to be called by an action later -->
<t:data value="#{controller.movies}" var="movies" id="movies" success="renderMovies" lazy="true" widgetVar="movieLoader" />

<!-- Button to trigger lazy loading and rendering -->
<a href="#" class="button" onclick="TW('movieLoader').load()">Load via Widget Call</a>

<!-- Load data by re-rendering, JSF-style -->
<t:commandButton value="Load by re-rendering Widget" render=":movies"/>

Info

Tag name	data
Component type	io.tornadofaces.component.Data
Renderer type	io.tornadofaces.component.DataRenderer

Attributes

Name	Description	Required
value	The value expression that will be rendered as a JavaScript object	true
var	The client side variable name of the resulting object. Can be left blank if you intend to access the data via `Widget.val()` only.	false
json	The value will be rendered as a JSON object. Default true.	false
lazy	A lazy Data object can be retrieved via a call to `Widget.load()`.	false
success	Client callback that will be called when the data is available or reloaded. The first argument is the data itself, the other is a boolean indicating wether this was the initial load or not.	false
widgetVar	Widget variable name, accessible via TW('widgetVar') and TornadoFaces.widgets.widgetVar. Use this to `load()` the data or get the data via `val()`. Note that the Data component must be wrapped in a Form for the load() function to work.	false

Client Side API

Widget: TornadoFaces.widget.Data

Method	Return type	Description
load()	function	Load or reload the data. If a success callback is configured, it will be called when the data is available.
isDataAvailable()	boolean	Checks if data is available. Typically, this will return false if lazy is true and load() has not been called yet.
val()	object	Retrieves the data. Also available via the var attribute name.