Minesweeper

First published to the Play Store on September 15, 2015.

• Instructions
  • Long Click - Remove tile and uncover square to display number of adjacent squares with mines.
  • Normal Click - Add or remove flag.
  • Click Finish to stop the timer and calculate results.
  • Click Reset to start a new game.

Implementation Details

All source code has been written exclusively for this application.

Primary components

• GameManager - (source)
  • Glue layer between activity, game, and views.
  • Allows the activity to listen for game state events (e.g., win/loss events, mine flag placement events, etc.)
  • Resets the Game object and BoardLayoutView when the user starts a new game.
• Game - (source)
  • Holds game state.
    • Has knowledge of mine placement, adjacent mines count for each square on the board.
    • Also holds references to all TileView objects on the board.
  • Checks all user actions to determine if the action is allowed.
    • Publishes win and loss events to the GameManager.
    • Triggers view changes based on game state.
    • Views post actions to the event bus, and the Game object is responsible for updating the game state and responding to those actions accordingly.
  • Uses Breadth First Search to uncover adjacent blank squares.
• Board - (source)
  • Randomly places mines within the board grid.
  • Calculates adjacent mine count for each square on the grid.

Graphics / UI

This application utilizes custom View and Drawable objects. No static BitmapDrawable objects are used. All Drawable objects are programmatically created to allow for ease of customization.

The above graphic includes the following graphical components: TileView, ConcentricCirclesDrawable, and BeveledTileDrawable.

• Custom Views
  • BoardLayoutView - (source)
    • Used to draw the underlying game board and layout tiles.
    • Custom ViewGroup that supports custom XML view attributes.
  • TileView - (source)
    • Uses a LayerListDrawable that switches the graphic displayed for each independent tile based on three states: COVERED, FLAGGED_AS_MINE, and UNCOVERED.
    • Click listeners:
      • Long click: Attempts to uncover a tile to display the tile's adjacent mine count.
      • Click: toggles the mine flag for the tile.
• Drawables
  • BeveledTileDrawable - (source)
    • Used for game tiles, buttons, and text views.
    • BeveledTileButton and BeveledTileTextView both support custom XML view attributes that allow customization of colors.
  • ConcentricCirclesDrawable - (source)
    • Used for mines, mine flags, and status indicator.
  • TextDrawable - (source)
    • Used to provide adjacent mine count. Necessary since each tile uses a LevelListDrawable.

Upcoming features

• Add GameState parcelable object.
• Support screen orientation.
• Persist game state to SQLite.
• Add high score tracking.
• Add online high score tracking.
• Add navigation drawer.
• Allow user to change grid size.
• Increase test coverage.

Libraries used:

• Otto - Event bus to decouple objects. All event publishing is done to a central Game object.
• ButterKnife - Concise view lookup.