Skip to content

Sprint 2 – Game Logic & Controls

School of Engineering and Technology, University of Washington Tacoma
TCSS 305 Programming Practicum, Winter 2026
Value: 10% of the course grade

Due Date

Sunday, 8 March 2026, 23:59:59

Description

Sprint 2 brings your Tetris GUI to life. You will connect the visual components from Sprint 1 to the back-end model using the Observer Design Pattern (PropertyChangeListener), add keyboard controls so the player can move and rotate pieces, and drive the game forward with a javax.swing.Timer.

The key architectural principle in this sprint: the GUI never manipulates game state directly. Every user action calls a single method on the GameControls API, and every visual update is triggered by a PropertyChangeEvent from the model. This clean separation between front-end and back-end is the Observer pattern in action.

Learning Objectives

By completing this sprint, you will:

  • Apply the Observer Design Pattern using PropertyChangeListener and PropertyChangeEvent
  • Connect GUI components to a back-end model through event-based communication
  • Use javax.swing.Timer to drive periodic game updates
  • Implement keyboard input handling with KeyListener
  • Practice the principle of separation of concerns between front-end and back-end

Before You Begin

Ensure you have completed:

Requirements

Requirement 1: Branch Setup

Create a branch from your main branch called sprint2. All Sprint 2 work should be committed to this branch.

Caution

Do NOT commit, merge, or alter the sprint2 branch after the due date/time. I will ignore any commits after the deadline.

Requirement 2: Top-Level GUI Class Setup

Guide

In the top-most GUI class (JFrame or top-level JPanel):

Model Reference:

  • Add a field that holds a reference to the primary model object (TetrisGame)
  • Only instantiate one TetrisGame object — this single instance is shared across all components that need it

Timer Setup:

  • Instantiate a javax.swing.Timer and store a reference to it
  • Determine an appropriate tick interval (how often the timer fires)
  • Add an ActionListener to the Timer that calls the appropriate method in the GameControls API to advance the game by one step

Single Responsibility

The Timer's ActionListener should ONLY call a single method in the GameControls API. It should NOT call repaint(), move shapes, update scores, or do any other work. The model will fire PropertyChangeEvents that trigger those updates.

Requirement 3: PropertyChangeListener for GameState

Guide

Implement PropertyChangeListener in the top-level GUI class and register it with the TetrisGame object. Listen for game state changes:

Respond to each state:

GameState Action
NEW Set up the GUI for a new game (this may be nothing to do)
RUNNING Start the Timer
PAUSED Stop the Timer
OVER No requirement for this sprint

Tip

Think about what "set up the GUI for a new game" means. If the user starts a second game, what needs to reset?

Requirement 4: Menu Integration

Connect the New Game menu item from Sprint 1 to the back-end. When the user selects New Game, call the correct method from the GameControls API.

Single Responsibility

The menu action should ONLY call a single method in the GameControls API — do not directly start timers, reset panels, or change any GUI state. The model's PropertyChangeEvents will handle those updates through the listeners you implement in other requirements.

Requirement 5: KeyListener for Game Controls

Guide

  • NEW Handling Key Events — KeyListener, KeyAdapter, and three patterns for mapping keys to actions (if-chain, Map, switch expression)

Add a KeyListener to the top-most GUI JPanel. Each key press should ONLY call a single method in the GameControls API — no direct GUI changes.

Action Key Handler
Move piece left Call appropriate GameControls method
Move piece right Call appropriate GameControls method
Move piece down one Call appropriate GameControls method
Drop piece Call appropriate GameControls method
Rotate piece Call appropriate GameControls method
Pause game Call appropriate GameControls method

Tip

Pay attention to the reported GameState of the TetrisGame to know when the game is paused. Your key handler should check the current state — some actions should be ignored when the game is paused.

Requirement 6: Board Panel PropertyChangeListener

Guide

NEW The Observer Pattern — Implementing PropertyChangeListener to receive model updates

In the GUI class containing the Tetris Board visual (JPanel):

  1. Implement PropertyChangeListener
  2. Register this object with the TetrisGame's property change support
  3. Listen for:
  4. Paint/draw/fill the current moving piece and frozen blocks
  5. The display must update when new PropertyChangeEvents are received

Note

In Sprint 1, you drew pieces using hardcoded test data. Now, your paintComponent code receives live data from the model via property change events. Your drawing logic from Sprint 1 should work with minimal changes — the data types are the same.

Requirement 7: Next Piece Panel PropertyChangeListener

Guide

NEW The Observer Pattern — Implementing PropertyChangeListener to receive model updates

In the GUI class containing the Next Piece visual (JPanel):

  1. Implement PropertyChangeListener
  2. Register this object with the TetrisGame's property change support
  3. Listen for:
  4. Paint/draw/fill the next piece — it must be visible, centered, identifiable, and update correctly

Not Required for Sprint 2

The following are not required for this sprint:

  • Ending a game (reacting to GameState.OVER)
  • Scoring or level tracking
  • Finalized styles or look and feel
  • Extra features (sound, themes, high scores, etc.)

These will be addressed in Sprint 3.

Requirement 8: Daily Meetings (2 Required)

Hold at least 2 daily meetings during this sprint. Create a Google Doc to document your meetings. Each meeting should contain:

  • Date and time
  • Members who attended
  • Location/method (Discord voice/video, Zoom, in-person)
  • Each group member answers:
    1. What did you do since the last meeting?
    2. What will you do before the next meeting?
    3. Is there anything the group can do to help you?

Put the link to the Google Doc in your README.md (with view access).

Tip

These meetings mirror daily stand-ups used in professional Agile/Scrum teams. Keep them focused — 15 minutes is a good target.

Requirement 9: Executive Summary

Add the following sections to your executive-summary.md:

  • Sprint 2 Contributions — for each group member, describe their contribution to Sprint 2
  • Sprint 2 Meetings — link to meeting minutes, describe other meetings (where/when/how, what was discussed), describe primary forms of communication besides formal meetings
  • Sprint 2 Comments — document any issues, ideas, code weirdness, etc.

Important

Keep all previous sprint entries intact. The executive summary is a living document.

Guide Reference

Guide Description
NEW Introduction to Design Patterns What design patterns are, why they matter, and the patterns used in this project
NEW The Observer Pattern PropertyChangeListener, PropertyChangeSupport, firing and handling property change events
NEW Model-View-Controller (MVC) Separating Model (game logic), View (panels), and Controller (input handling)
NEW The Strategy Pattern Map-based strategy pattern used in the back-end API for move validation
NEW Handling Key Events KeyListener, KeyAdapter, and three patterns for mapping keys to game actions
NEW Animation with javax.swing.Timer EDT-safe timer for driving the game loop, start/stop/setDelay
Adding Event Handlers ActionListener patterns for menu items and timer callbacks

Submission and Grading

Important

Start early — connecting the model to the GUI requires coordination across team members. Plan who is implementing which listeners.

Please see the rubric in Canvas for a breakdown of the grade for this sprint.

Submitting Your Work

  1. Ensure all Sprint 2 requirements are committed and pushed to your sprint2 branch
  2. Perform one merge from sprint2 into your main branch
  3. Push the merge to the remote repository

I will look at both the sprint2 and main branches. I will ignore any commits after the due date.

Tip

You can commit and push to your sprint2 branch as often as you like. Only perform one merge into main at the end.