WebWindow

Web Window tracker. This is a game object that controls and remembers the state of a "window" in the browser user interface. By "window", we basically mean an HTML page, which might reside at the top level of the browser itself, or inside an IFRAME element within an enclosing page.

Each WebWindow class corresponds to a particular HTML page that we serve the client. The HTML page is the expression of the window in the browser, and the WebWindow object is the expression of the same information in the game program. The two are different facets of the same conceptual UI object. The reason we need the two separate expressions is that the server controls everything, but the client has to do the actual display work, and the two parts of the program speak different languages - the server is TADS, and the client is HTML.

The WebWindow object on the server lets us easily reconstruct the UI state in a newly opened browser window, or when the user performs a page refresh. This object's job is to send information to the client on demand that allows the client to display the page in its current state.

Note that a given WebWindow/HTML page combination can be used more than once within the same UI. The pages defined in the library are designed to be generic and reusable, so you might use the same window class more than once for different purposes within the UI. The library pages can also be subclassed, by subclassing the WebWindow object and creating a customized copy of the corresponding HTML page resource.

class WebWindow : WebResourceResFile

The URL path to the window's HTML definition file, as seen by the browser. For the pre-defined library window types, we expose the HTML file in the root of the URL namespace - e.g., "/main.htm". The files are actually stored in the /webuires folder, but we expose them to the browser as though they were in the root folder to make embedded object references on the pages simpler. The browser figures the path to an embedded object relative to the containing page, so by placing the containing page in the root folder, embedded object paths don't have to worry about referencing parent folders.

Get the window's current state. This returns a string containing an XML fragment that describes the state of the window. This information is sent to the HTML page when the browser asks for the current layout state when first loaded or when the page is refreshed. The XML format for each subclass is specific to the Javascript on the class's HTML page.