netui-data:callControl Tag

<netui-data:callControl> Tag

This tag is used to call a method on a control file (either a JCS or JCX file).

Syntax

<netui-data:callControl
    controlId="string_controlId"
    [failOnError="boolean_failOnError"]
    method="string_method"
    [resultId="string_resultId"] />

Description

This tag is used to call a method on a control file (either a JCS or JCX file).

The controlId attribute is used to specify the control file to be called. The value returned by the method will be set in the {pageContext...} data binding context under the attribute specified by the resultId attribute.

For example, if you call a control with the following <netui-data:callControl> tag...

    <netui-data:callControl 
          controlId="helloWorldControl" 
          method="hello" 
          resultId="helloMessage" 
          />

...the result of the call is stored in the {pageContext...} data binding context under the attribute helloMessage.

The result can be retrieved with the data binding expression {pageContext.helloMessage}

   <netui:label value="{pageContext.helloMessage}"/>

In a scriptlet, the result can be retrieved by calling the getAttribute() method on the javax.servlet.jsp.PageContext object:

    <%= pageContext.getAttribute("helloMessage") %>

The <netui-data:callControl> tag must be used in conjunction with the <netui-data:declareControl> tag. The <netui-data:declareControl> tag is used to give the control a controlId:

    <netui-data:declareControl 
          type="tagSamples.netui_databinding.callControl.HelloWorldControl" 
          controlId="helloWorldControl" 
          />

Then the <netui-data:callControl> refers to the control using that controlId:

    <netui-data:callControl 
          controlId="helloWorldControl" 
          method="hello" 
          resultId="helloMessage" 
          />

Note that only synchronous methods can be called with <netui:callControl>. For handling asynchronous methods see the help topic Calling Web Services and Custom Java Controls From A Page Flow

Attributes

controlId

The control on which to invoke a method. This value must already be specified in a <netui-data:declareControl> tag.

Required	Supports runtime expression evaluation	Data bindable
Yes	No	Yes

failOnError

Boolean. If set to true, any errors occuring while invoking the control method will be be reported in-line on the JSP page.

Required	Supports runtime expression evaluation	Data bindable
No	No	No

method

The name of the method to invoke

Required	Supports runtime expression evaluation	Data bindable
Yes	No	No

resultId

The data returned by the method is loaded into the PageContext object, under this property name.

Required	Supports runtime expression evaluation	Data bindable
No	No	No

Sample

In this sample, a JSP page uses a <netui-data:declareControl> tag to declare a control. Then the <netui-data:callControl> tag calls the insertProduct method on that control. The insertProduct method is called with parameters, provided by <netui-data:methodParameter> tags.

    <netui-data:declareControl type="dbControls.ProductsDBControl" controlId="productsDBControl"/>
  
    <netui-data:callControl controlId="productsDBControl" method="insertProduct">
        <netui-data:methodParameter value="1"/>
        <netui-data:methodParameter value='ACME RacePro Crankset'/>
        <netui-data:methodParameter value="280.00"/>
        <netui-data:methodParameter value="acme_racepro_crankset.jpg"/>
        <netui-data:methodParameter value="true"/>
    </netui-data:callControl>

Code Sample