Key Canvas : 2D « J2ME « Java





Key Canvas

import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Font;
import javax.microedition.lcdui.Graphics;

public class KeyCanvas extends Canvas {
  private Font mFont;

  private String mMessage = "[Press keys]";

  public KeyCanvas() {
    mFont = Font.getFont(Font.FACE_PROPORTIONAL, Font.STYLE_PLAIN, Font.SIZE_MEDIUM);
  }

  public void paint(Graphics g) {
    int w = getWidth();
    int h = getHeight();

    // Clear the Canvas.
    g.setGrayScale(255);
    g.fillRect(0, 0, w - 1, h - 1);
    g.setGrayScale(0);
    g.drawRect(0, 0, w - 1, h - 1);

    g.setFont(mFont);

    int x = w / 2;
    int y = h / 2;

    g.drawString(mMessage, x, y, Graphics.BASELINE | Graphics.HCENTER);
  }

  protected void keyPressed(int keyCode) {
    int gameAction = getGameAction(keyCode);
    switch (gameAction) {
    case UP:
      mMessage = "UP";
      break;
    case DOWN:
      mMessage = "DOWN";
      break;
    case LEFT:
      mMessage = "LEFT";
      break;
    case RIGHT:
      mMessage = "RIGHT";
      break;
    case FIRE:
      mMessage = "FIRE";
      break;
    case GAME_A:
      mMessage = "GAME_A";
      break;
    case GAME_B:
      mMessage = "GAME_B";
      break;
    case GAME_C:
      mMessage = "GAME_C";
      break;
    case GAME_D:
      mMessage = "GAME_D";
      break;
    default:
      mMessage = "";
      break;
    }
    repaint();
  }
}



           
       










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