Monitoring Events on the Client
The ongoing Ajax requests can be monitored by using the onevent attribute of the f:ajax tag. The value of this attribute is the name of a JavaScript function. JavaServer Faces calls the onevent function at each stage of the processing of an Ajax request: begin, complete, and success.
When calling the JavaScript function assigned to the onevent property, JavaServer Faces passes a data object to it. The data object contains the properties listed in Table 11-3.
Property |
Description |
---|---|
responseXML |
The response to the Ajax call in XML format |
responseText |
The response to the Ajax call in text format |
responseCode |
The response to the Ajax call in numeric code |
source |
The source of the current Ajax event: the DOM element |
status |
The status of the current Ajax call: begin, complete, or success |
type |
The type of the Ajax call: event |
By using the status property of the data object, you can identify the current status of the Ajax request and monitor its progress. In the following example, monitormyajaxevent is a JavaScript function that monitors the Ajax request sent by the event:
<f:ajax event="click" render="errormessage" onevent="monitormyajaxevent"/>