1. Framework for Interactive Applications
Matt Korchinsky
Advisor: Aaron Cass

2. Agenda Problem Statement Background and Current Work
Design and Implementation
Issues
Evaluation
Future Work

3. Problems to Solve
Java's Listening event system is sometimes difficult to understand for beginners.
Java has a wide array of classes for use with interactive applications
Creating large scale applications can be difficult when both of these factors are combined

4. Background & Current Work
Different event system already implemented for use with C++
Learned how to use QT framework while employed this summer (
C++ version uses code generation script
Decided to replicate the event system using Java to replace the current listening system.

5. Example

6. New Event System

7. Design & Implementation I
Designed for use with Java events as well as user defined events
One simple class manages all connections and handles listening for Java events

8. Design & Implementation II
Event system uses connect method to connect a “signal” to a “slot”
Slots are implemented methods signals are not
When connecting Java events, listeners must be used

9. Design & Implementation III
Emit method allows users to emit their own signals when appropriate
Looks up the correct slot and calls it

10. Design & Implementation IV
Uses Java Reflection to correctly implement “Signal – Slot” relationship instead of interfaces
When correct slot is found, the method is called using the invoke method

11. Coding Problems Need to listen to handle Java events
Connecting Java events to emit user defined events
Invoking user defined methods when events occur

12. Data Structures Problem
Java HashMap can only relate two objects, the key and the value
Four objects are involved in one connection

13. Evaluation Gave three experienced students the framework source code
Asked them to create a simple application containing two buttons using the framework
Asked them to create the same type of application using Java listeners
Gave them a questionnaire to evaluate the effectiveness of the new event system

14. Future Work Larger set of custom widgets for interactive applications
Test this framework in “Large Scale Software Design” class to evaluate effectiveness for event programming beginners

15. Questions?