December 15, 2001

SDK: EVENT DRIVEN ARCHITECTURE

How it works?

In the Windows application all the inputs are taken in placed in the message queue, then it is processed.

1. In Windows an application does not make explicit call to read from the key board or mouse. But Windows receives all input from Kb, mouse etc in a SYSTEM QUEUE.

2. Queue's responsibility is to redirect the input to appropriate program queue. (As we know that several program is running on the system)

3. When the application is ready to process the input, it reads from the queue and dispatches the messages.

4. All the Input from the input device is accepted in a uniform format called as Input Message. All the input messages have uniform properties of the input.

5. All the keyboard input messages are sent directly to current window. Mouse Messages are handled differently with the object under the mouse cursor.