Application type: Controller-Subscriber
UI components used: Chat, PresentationSWF, MessageBox, ConnectionLight
Flash objects: Camera, Microphone, NetConnection
SSAS objects: Application, Client
Key points: Dynamically Switching a Stream Source
The Virtual Classroom application is a good foundation for an elaborate e-Learning application. This tutorial will only focus on the communication part of e-Learning, but you could extend the application with a testing module, classroom management, or grading.
The application itself uses a controller and subscriber model as presented in Chapter 9, "STEP 9: Controller and Subscriber Applications." The interface is simple, but elegant. Remember, the interface should not distract the student from what the teacher is presenting. The exercise is similar to the one you did in Chapter 9, but with one big difference. Where that exercise had audio-only chat using the prebuilt AudioConference component, this application uses a real-time video source switch controlled by the teacher. This switch lets the teacher invite a student to answer a question. You know the trick: You're falling asleep in class, and the teacher catches you and makes you answer a question that you missed while dozing. In this application, a student can "raise her hand" to ask the teacher a question, or the teacher can trigger the student's camera and microphone?sort of like bringing her to the front of the class.