9. A method implemented in instructions executed by a computer processor of using a UI XML schema to define an application's graphical layout, the method comprising: defining a UI XML schema in which a valid UI XML document includes at least a view element in which the name of the application view is provided; specifying a graphical layout of at least one user interface component in elements and attributes in the UI XML document; in response to an application being launched, instantiating a runtime object that represents the application view and causing the at least one user interface component to be rendered on a graphical display in, accordance with the graphical layout defined in the UI XML document; binding the at least one user interface component to a set of data in a data model, the set of data identified by an XPath expression of an XBind; and in response to a trigger event: identifying an emitter view object as a source of the trigger event based on an indicator included with an XBind; and using a context of the emitter view object to execute computational logic of the application, the computational logic including at least one Action URL for submission to a communicator.
10. The method recited in claim 9 , wherein the user interface component is defined in accordance with component APIs that accept logic for setting data from a data model on the user interface component and updating data that is visually rendered by the user interface component when the data model experiences a data update.