Initializing with MVVM
You can initialize and configure each Kendo UI widget through the data attributes.
Initialization from data attributes is convenient when you have a lot of Kendo UI widgets on the page, because the widget configuration is declared within the target element.
The Model View View-Model (MVVM) kendo.bind method uses the declarative approach to automatically instantiate multiple widgets in an existing DOM element.
The following example demonstrates how to initialize a Kendo UI NumericTextBox and a DropDownList by using the data attributes. The kendo.bind($("#container")) statement finds all elements that have the role data attribute set and initializes the respective Kendo UI widgets.
<div id="container">
<input data-role="numerictextbox" />
<input data-role="dropdownlist" style="width: 100%;" />
</div>
<script>
kendo.bind($("#container"), {});
</script>
The value of the
roledata attribute is the lower-case name of the widget—"autocomplete","dropdownlist", and so on.
By using the data attribute you can also perform the following operations:
- Set up the configuration options
- Subscribe to events
- Set up the event handlers
- Set up the data source
- Manage the templates
Setting the Configuration Options
Each configuration option can be set with the data attribute of the target element. Add the "data-" prefix to the name of the configuration option and specify the option value—for example, data-delay="100".
The camelCase options are set through dash-separated attributes. For example, the
ignoreCaseoption of the AutoComplete is set throughdata-ignore-case.
Options which start with data do not require an additional "data" in the attribute name. For example, the dataTextField option is set through the data-text-field attribute and dataSource is set through the data-source attribute. Complex configuration options are set as JavaScript object literals—for example, data-source="{data: [{name: 'John Doe'},{name: 'Jane Doe'}]}".
The following example demonstrates how to configure Kendo UI widgets with data attributes.
<div id="container">
<input data-role="autocomplete"
data-ignore-case="true"
data-text-field="name"
data-source="{data: [{name: 'John Doe'},{name: 'Jane Doe'}]}" />
</div>
<script>
kendo.bind($("#container"), {});
</script>
Subscribing to Events
You can subscribe to Kendo UI widget events by using data attributes. The value of the data attribute is resolved to a JavaScript function that is available in the global scope.
The following example demonstrates how to subscribe to a Kendo UI widget event through a data attribute.
<div id="container">
<input data-role="numerictextbox" data-change="numerictextbox_change" />
</div>
<script>
function numerictextbox_change(e) {
// Handle the "change" event.
}
kendo.bind($("#container"));
</script>
Setting the Event Handlers
You can also set event handlers to member functions. For example, an event data attribute can be set to foo.bar which is resolved as the bar method of the foo object that is available in the global scope.
The following example demonstrates how to use a member function as an event handler.
<div id="container">
<input data-role="numerictextbox" data-change="handler.numerictextbox_change" />
</div>
<script>
var handler = {
numerictextbox_change: function (e) {
// Handle the "change" event.
}
};
kendo.bind($("#container"));
</script>
Setting the Data Source
You can also set the Data Source of data-bound Kendo UI widgets through a data attribute. The value can be a JavaScript object, array, or a variable available in the global scope.
The following example demonstrates how to set the data source of a Kendo UI widget to a JavaScript object.
<div id="container">
<input data-role="autocomplete" data-source="{data:['One', 'Two']}" />
</div>
<script>
kendo.bind($("#container"));
</script>
The following example demonstrates how to set the data source of a Kendo UI widget to a JavaScript array.
<div id="container">
<input data-role="autocomplete" data-source="['One', 'Two']" />
</div>
<script>
kendo.bind($("#container"));
</script>
The following example demonstrates how to set the data source of a Kendo UI widget to a variable that is available in the global scope.
<div id="container">
<input data-role="autocomplete" data-source="dataSource" />
</div>
<script>
var dataSource = new kendo.data.DataSource( {
data: [ "One", "Two" ]
});
kendo.bind($("#container"));
</script>
Managing Templates
By using the data attributes, you can also set the template configuration. The attribute value is resolved as the id attribute of a script element with the template contents.
The following example demonstrates how to set the template of a Kendo UI widget by using the data attribute.
<div id="container">
<input data-role="autocomplete"
data-source="[{firstName:'John', lastName: 'Doe'}, {firstName:'Jane', lastName: 'Doe'}]"
data-text-field="firstName"
data-template="template" />
</div>
<script id="template" type="text/x-kendo-template">
<span>#: firstName # #: lastName #</span>
</script>
<script>
kendo.bind($("#container"));
</script>