Information Flow

When the user requests a page containing DOUI interfaces, a concise sequence of operations occurs:

1. The user requests the page from the LumisXP Server (Front controller);
2. The LumisXP Server, as it is a page request, delegates processing to the PresentationController, responsible for rendering portal pages;
3. The PresentationController determines which interfaces and respective services make up the requested page and requests the ServiceContainer to render each interface;
4. The ServiceContainer identifies that these are DOUI interfaces and requests the DouiServiceInterface class to render the interface;
5. The class DouiServiceInterface executes the lifecycle of a DOUI interface, namely:

   In the process action:

   1. The sources, controls, and process actions are instantiated;
   2. The controls restore their state, reading from the Request or populated by the sources. Controls may inject parameters into the sources to, for example, serve as filters;
   3. The controls inject their values as parameters into the process actions;
   4. The process actions and their respective process action handlers are executed, optionally returning rendering parameters.

   In the render (rendering) process:

   5. The sources and controls are instantiated;
   6. The controls restore their state, reading from the Request or populated by the sources. Controls may inject parameters into the sources to, for example, serve as filters;
   7. The controls update the XML of the interface with their values;
6. The PresentationController uses the XSL of the interface to transform the XML into HTML;
7. The PresentationController returns the HTML to the user's browser.

The figure below summarizes the information flow of the DOUI framework: