The framework is built upon a concept of a page life cycle, which is a general concept and not related to ApplinX host applications directly. The life cycle of a page is declared by the top context class:

JSP: com.sabratec.j2ee.framework.web.GXWebPageContext.

.NET: System.Web.UI.Page

Each page decides which is its class by declaring the root node: <gx:html gx_context="<CONTEXT_CLASS>"> and closing it with </gx:html> as the end tag.

Each dynamic tag should be set with a prefix of "gx:" for example: <gx:input id="CustomerId"/>. The <CONTEXT_CLASS> is initialized and starts the page Life cycle:

• gx_onInit (JSP) /OnInit (.NET) :

  Used to initialize page and/or project settings, and register to events. For example setting the ApplinX configuration and registering classes to user exits.

• gx_onLoad (JSP) /OnLoad (.NET) :

  Used to fill the tags with run-time data from data sources. Host data will be used in lower inheritance level to fill the tags with host data. Page.IsPostBack (.NET)/ gx_isPostBack (JSP) can determine if the page is first called, or submitted back to itself.

• Post back:

  Performed automatically by the framework. Each page is submitted to itself using server side buttons/links:

  JSP:

  <gx:input id= myBtn  onserverclick= <FUNC_NAME> /> 
  <gx:a id= myLinkBtn onserverclick= <FUNC_NAME> >Send</a>

  .NET:

  <input id="myBtn" runat="server" onserverclick="< FUNC_NAME>"/> 
  <a id="myLinkBtn" runat="server" onserverclick="<FUNC_NAME>">Send</a> 

  The <FUNC_NAME> will be activated automatically upon a user click, and it will be used to perform update actions, re-queries or jumping to another page using redirect. In the context class the developer should hold a function in the format:

  Public void <SERVER_FUNC>(){ 
        // code in response to the	server click event. 
  } 

  Can be also fired using JavaScript using: gx_postBack("<SERVER_FUNC>");

  public void <SERVER_FUNC>(Object sender,EventArgs e){ 
        // code in response to the server click event. 
  } 

  In JSP the event can also be fired using JavaScript: gx_postBack("<SERVER_FUNC>");

• gx_preRender (JSP) / PreRender event (.NET):

  Used to add logic after any post back event for example: refilling the page.

• Controls/Tags rendering:

  The dynamic tags are rendered with runtime content and attributes manipulation performed by the tagsAccessor in the previous stages of the life cycle.

• gx_onUnload(JSP)/OnUnload (.NET):

  Occurs when the page ends. Used to release any relevant resources.

• gx_onError (JSP)/Error event (.NET):

  Used for capturing errors. Any known thrown or runtime error is captured and can be analyzed by the developer.