PrimeFaces 處理 Ajax request 過程中所產生的 callbacks 及 events

在執行 Ajax Request 的前後， 我們可以有機會執行 Javascript 完成瀏覽器上的操作。過程中的一連串的過程如下：

• User clicks button in client
• onclick JavaScript code is executed
• JavaScript prepares ajax request based on process and current HTML DOM tree
• onstart JavaScript code is executed
• JavaScript sends ajax request from client to server
• JSF retrieves ajax request
• JSF processes the request lifecycle on JSF component tree based on process
• actionListener JSF backing bean method is executed
• action JSF backing bean method is executed
• JSF prepares ajax response based on update and current JSF component tree
• JSF sends ajax response from server to client
• JavaScript retrieves ajax response
  • if HTTP response status is 200, onsuccess JavaScript code is executed
  • else if HTTP response status is 500, onerror JavaScript code is executed
• JavaScript performs update based on ajax response and current HTML DOM tree
• oncomplete JavaScript code is executed

References: http://stackoverflow.com/a/20146879