Java by API/javax.microedition.lcdui/Canvas

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Версия от 14:49, 31 мая 2010; Admin (обсуждение | вклад) (1 версия)
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Canvas.DOWN

 
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.midlet.MIDlet;
public class Navigate2MIDlet extends MIDlet implements CommandListener {
  private Command exitCommand;
  Displayable nd;
  Image image = null;
  public Navigate2MIDlet() {
    try {
      image = Image.createImage("/J.png");
    } catch (Exception e) {
    }
    Display display = Display.getDisplay(this);
    nd = new Navigate2Canvas(image);
    exitCommand = new Command("exit", Command.EXIT, 1);
    nd.addCommand(exitCommand);
    nd.setCommandListener(this);
    display.setCurrent(nd);
  }
  public void startApp() {
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command c, Displayable s) {
    notifyDestroyed();
  }
}
class Navigate2Canvas extends Canvas {
  private Image image;
  private int newX = 0;
  private int newY = 0;
  private int stepX = 0;
  private int stepY = 0;
  public Navigate2Canvas(Image image) {
    this.image = image;
    newX = 0;
    newY = 0;
    stepX = getWidth() / 4;
    stepY = getHeight() / 4;
  }
  public void steppingXY(int x, int y) {
    newX += x;
    newY += y;
  }
  public void paint(Graphics g) {
    int width = this.getWidth();
    int height = this.getHeight();
    g.setGrayScale(255);
    g.fillRect(0, 0, width - 1, height - 1);
    g.setGrayScale(0);
    g.drawRect(0, 0, width - 1, height - 1);
    g.translate(newX, newY);
    g.drawImage(image, 0, 0, g.TOP | g.LEFT);
  }
  protected void keyPressed(int keyCode) {
    int gameaction = getGameAction(keyCode);
    switch (gameaction) {
    case UP:
      steppingXY(0, stepY);
      break;
    case DOWN:
      steppingXY(0, -stepY);
      break;
    case LEFT:
      steppingXY(stepX, 0);
      break;
    case RIGHT:
      steppingXY(-stepX, 0);
      break;
    }
    repaint();
  }
}





Canvas.FIRE

 

import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.midlet.MIDlet;
public class GameActionMIDlet extends MIDlet implements CommandListener {
  private Command exitCommand;
  Display display;
  Displayable d;
  public void startApp() {
    Display display = Display.getDisplay(this);
    d = new GameActionCanvas();
    exitCommand = new Command("Exit", Command.EXIT, 1);
    d.addCommand(exitCommand);
    d.setCommandListener(this);
    display.setCurrent(d);
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command c, Displayable s) {
    notifyDestroyed();
  }
}
class GameActionCanvas extends Canvas {
  int width = 0;
  int height = 0;
  String aMessage = "message";
  public void paint(Graphics g) {
    width = getWidth();
    height = getHeight();
    g.setGrayScale(255);
    g.fillRect(0, 0, width - 1, height - 1);
    g.setGrayScale(0);
    g.drawRect(0, 0, width - 1, height - 1);
    g.drawString(aMessage, 10, 10, Graphics.TOP | Graphics.LEFT);
  }
  protected void keyPressed(int keyCode) {
    int gameAction = getGameAction(keyCode);
    switch (gameAction) {
    case UP:
      aMessage = "Up";
      break;
    case DOWN:
      aMessage = "Down";
      break;
    case LEFT:
      aMessage = "Left";
      break;
    case RIGHT:
      aMessage = "Right";
      break;
    case FIRE:
      aMessage = "Send";
      break;
    case GAME_A:
      aMessage = "GAME_A";
      break;
    case GAME_B:
      aMessage = "GAME_B";
      break;
    case GAME_C:
      aMessage = "GAME_C";
      break;
    case GAME_D:
      aMessage = "GAME_D";
      break;
    default:
      aMessage = "";
      break;
    }
    repaint();
  }
}





Canvas.GAME_D

 

import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.midlet.MIDlet;
public class GameActionMIDlet extends MIDlet implements CommandListener {
  private Command exitCommand;
  Display display;
  Displayable d;
  public void startApp() {
    Display display = Display.getDisplay(this);
    d = new GameActionCanvas();
    exitCommand = new Command("Exit", Command.EXIT, 1);
    d.addCommand(exitCommand);
    d.setCommandListener(this);
    display.setCurrent(d);
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command c, Displayable s) {
    notifyDestroyed();
  }
}
class GameActionCanvas extends Canvas {
  int width = 0;
  int height = 0;
  String aMessage = "message";
  public void paint(Graphics g) {
    width = getWidth();
    height = getHeight();
    g.setGrayScale(255);
    g.fillRect(0, 0, width - 1, height - 1);
    g.setGrayScale(0);
    g.drawRect(0, 0, width - 1, height - 1);
    g.drawString(aMessage, 10, 10, Graphics.TOP | Graphics.LEFT);
  }
  protected void keyPressed(int keyCode) {
    int gameAction = getGameAction(keyCode);
    switch (gameAction) {
    case UP:
      aMessage = "Up";
      break;
    case DOWN:
      aMessage = "Down";
      break;
    case LEFT:
      aMessage = "Left";
      break;
    case RIGHT:
      aMessage = "Right";
      break;
    case FIRE:
      aMessage = "Send";
      break;
    case GAME_A:
      aMessage = "GAME_A";
      break;
    case GAME_B:
      aMessage = "GAME_B";
      break;
    case GAME_C:
      aMessage = "GAME_C";
      break;
    case GAME_D:
      aMessage = "GAME_D";
      break;
    default:
      aMessage = "";
      break;
    }
    repaint();
  }
}





Canvas: getKeyName(int keyCode)

 

import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.midlet.MIDlet;
public class KeyEventsMIDlet extends MIDlet implements CommandListener {
  private Command exitCommand;
  Display display;
  Displayable d;
  public void startApp() {
    Display display = Display.getDisplay(this);
    d = new KeyEventsCanvas();
    exitCommand = new Command("Exit", Command.EXIT, 1);
    d.addCommand(exitCommand);
    d.setCommandListener(this);
    display.setCurrent(d);
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command c, Displayable s) {
    notifyDestroyed();
  }
}
class KeyEventsCanvas extends Canvas {
  int width = 0;
  int height = 0;
  String aMessage = "message";
  public void paint(Graphics g) {
    width = getWidth();
    height = getHeight();
    g.setGrayScale(255);
    g.fillRect(0, 0, width - 1, height - 1);
    g.setGrayScale(0);
    g.drawRect(0, 0, width - 1, height - 1);
    g.drawString(aMessage, 10, 10, Graphics.TOP | Graphics.LEFT);
  }
  protected void keyPressed(int keyCode) {
    aMessage = getKeyName(keyCode);
    if (aMessage.equals("2"))
      aMessage = "2";
    repaint();
  }
}





Canvas.getWidth()

 

import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.StringItem;
import javax.microedition.midlet.MIDlet;
public class AttributesMIDlet extends MIDlet 
                        implements CommandListener {
    private Display display;
        
    protected boolean started;
    private Command exitCommand;
    
    protected void startApp() {
        if (!started) {
            display = Display.getDisplay(this);
            Canvas canvas = new DummyCanvas();
            Form form = new Form("Attributes");
            exitCommand = new Command("Exit", Command.EXIT, 0);
            form.addCommand(exitCommand);
            
            boolean isColor = display.isColor();
            form.append(new StringItem(isColor ? "Colors: " : "Grays: ",
                                String.valueOf(display.numColors())));
            form.append(new StringItem("Width: ", String.valueOf(canvas.getWidth())));
            form.append(new StringItem("Height: ", String.valueOf(canvas.getHeight())));
            form.append(new StringItem("Pointer? ", String.valueOf(canvas.hasPointerEvents())));
            form.append(new StringItem("Motion? ",String.valueOf(canvas.hasPointerMotionEvents())));
            form.append(new StringItem("Repeat? ",String.valueOf(canvas.hasRepeatEvents())));
            form.append(new StringItem("Buffered? ", String.valueOf(canvas.isDoubleBuffered())));
            
            form.setCommandListener(this);
            display.setCurrent(form);
            
            started = true;
        }
    }
    protected void pauseApp() {
    }
    protected void destroyApp(boolean unconditional) {
    }
    public void commandAction(Command c, Displayable d) {
        if (c == exitCommand) {
            notifyDestroyed();
        }
    } 
    static class DummyCanvas extends Canvas {
        protected void paint(Graphics g) {
        }
    }
}





Canvas.hasPointerEvents()

 

import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.StringItem;
import javax.microedition.midlet.MIDlet;
public class AttributesMIDlet extends MIDlet 
                        implements CommandListener {
    private Display display;
        
    protected boolean started;
    private Command exitCommand;
    
    protected void startApp() {
        if (!started) {
            display = Display.getDisplay(this);
            Canvas canvas = new DummyCanvas();
            Form form = new Form("Attributes");
            exitCommand = new Command("Exit", Command.EXIT, 0);
            form.addCommand(exitCommand);
            
            boolean isColor = display.isColor();
            form.append(new StringItem(isColor ? "Colors: " : "Grays: ",
                                String.valueOf(display.numColors())));
            form.append(new StringItem("Width: ", String.valueOf(canvas.getWidth())));
            form.append(new StringItem("Height: ", String.valueOf(canvas.getHeight())));
            form.append(new StringItem("Pointer? ", String.valueOf(canvas.hasPointerEvents())));
            form.append(new StringItem("Motion? ",String.valueOf(canvas.hasPointerMotionEvents())));
            form.append(new StringItem("Repeat? ",String.valueOf(canvas.hasRepeatEvents())));
            form.append(new StringItem("Buffered? ", String.valueOf(canvas.isDoubleBuffered())));
            
            form.setCommandListener(this);
            display.setCurrent(form);
            
            started = true;
        }
    }
    protected void pauseApp() {
    }
    protected void destroyApp(boolean unconditional) {
    }
    public void commandAction(Command c, Displayable d) {
        if (c == exitCommand) {
            notifyDestroyed();
        }
    } 
    static class DummyCanvas extends Canvas {
        protected void paint(Graphics g) {
        }
    }
}





Canvas.hasRepeatEvents()

 

import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.StringItem;
import javax.microedition.midlet.MIDlet;
public class AttributesMIDlet extends MIDlet 
                        implements CommandListener {
    private Display display;
        
    protected boolean started;
    private Command exitCommand;
    
    protected void startApp() {
        if (!started) {
            display = Display.getDisplay(this);
            Canvas canvas = new DummyCanvas();
            Form form = new Form("Attributes");
            exitCommand = new Command("Exit", Command.EXIT, 0);
            form.addCommand(exitCommand);
            
            boolean isColor = display.isColor();
            form.append(new StringItem(isColor ? "Colors: " : "Grays: ",
                                String.valueOf(display.numColors())));
            form.append(new StringItem("Width: ", String.valueOf(canvas.getWidth())));
            form.append(new StringItem("Height: ", String.valueOf(canvas.getHeight())));
            form.append(new StringItem("Pointer? ", String.valueOf(canvas.hasPointerEvents())));
            form.append(new StringItem("Motion? ",String.valueOf(canvas.hasPointerMotionEvents())));
            form.append(new StringItem("Repeat? ",String.valueOf(canvas.hasRepeatEvents())));
            form.append(new StringItem("Buffered? ", String.valueOf(canvas.isDoubleBuffered())));
            
            form.setCommandListener(this);
            display.setCurrent(form);
            
            started = true;
        }
    }
    protected void pauseApp() {
    }
    protected void destroyApp(boolean unconditional) {
    }
    public void commandAction(Command c, Displayable d) {
        if (c == exitCommand) {
            notifyDestroyed();
        }
    } 
    static class DummyCanvas extends Canvas {
        protected void paint(Graphics g) {
        }
    }
}





Canvas.LEFT

 
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.midlet.MIDlet;
public class Navigate2MIDlet extends MIDlet implements CommandListener {
  private Command exitCommand;
  Displayable nd;
  Image image = null;
  public Navigate2MIDlet() {
    try {
      image = Image.createImage("/J.png");
    } catch (Exception e) {
    }
    Display display = Display.getDisplay(this);
    nd = new Navigate2Canvas(image);
    exitCommand = new Command("exit", Command.EXIT, 1);
    nd.addCommand(exitCommand);
    nd.setCommandListener(this);
    display.setCurrent(nd);
  }
  public void startApp() {
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command c, Displayable s) {
    notifyDestroyed();
  }
}
class Navigate2Canvas extends Canvas {
  private Image image;
  private int newX = 0;
  private int newY = 0;
  private int stepX = 0;
  private int stepY = 0;
  public Navigate2Canvas(Image image) {
    this.image = image;
    newX = 0;
    newY = 0;
    stepX = getWidth() / 4;
    stepY = getHeight() / 4;
  }
  public void steppingXY(int x, int y) {
    newX += x;
    newY += y;
  }
  public void paint(Graphics g) {
    int width = this.getWidth();
    int height = this.getHeight();
    g.setGrayScale(255);
    g.fillRect(0, 0, width - 1, height - 1);
    g.setGrayScale(0);
    g.drawRect(0, 0, width - 1, height - 1);
    g.translate(newX, newY);
    g.drawImage(image, 0, 0, g.TOP | g.LEFT);
  }
  protected void keyPressed(int keyCode) {
    int gameaction = getGameAction(keyCode);
    switch (gameaction) {
    case UP:
      steppingXY(0, stepY);
      break;
    case DOWN:
      steppingXY(0, -stepY);
      break;
    case LEFT:
      steppingXY(stepX, 0);
      break;
    case RIGHT:
      steppingXY(-stepX, 0);
      break;
    }
    repaint();
  }
}





Canvas.RIGHT

 
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.midlet.MIDlet;
public class Navigate2MIDlet extends MIDlet implements CommandListener {
  private Command exitCommand;
  Displayable nd;
  Image image = null;
  public Navigate2MIDlet() {
    try {
      image = Image.createImage("/J.png");
    } catch (Exception e) {
    }
    Display display = Display.getDisplay(this);
    nd = new Navigate2Canvas(image);
    exitCommand = new Command("exit", Command.EXIT, 1);
    nd.addCommand(exitCommand);
    nd.setCommandListener(this);
    display.setCurrent(nd);
  }
  public void startApp() {
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command c, Displayable s) {
    notifyDestroyed();
  }
}
class Navigate2Canvas extends Canvas {
  private Image image;
  private int newX = 0;
  private int newY = 0;
  private int stepX = 0;
  private int stepY = 0;
  public Navigate2Canvas(Image image) {
    this.image = image;
    newX = 0;
    newY = 0;
    stepX = getWidth() / 4;
    stepY = getHeight() / 4;
  }
  public void steppingXY(int x, int y) {
    newX += x;
    newY += y;
  }
  public void paint(Graphics g) {
    int width = this.getWidth();
    int height = this.getHeight();
    g.setGrayScale(255);
    g.fillRect(0, 0, width - 1, height - 1);
    g.setGrayScale(0);
    g.drawRect(0, 0, width - 1, height - 1);
    g.translate(newX, newY);
    g.drawImage(image, 0, 0, g.TOP | g.LEFT);
  }
  protected void keyPressed(int keyCode) {
    int gameaction = getGameAction(keyCode);
    switch (gameaction) {
    case UP:
      steppingXY(0, stepY);
      break;
    case DOWN:
      steppingXY(0, -stepY);
      break;
    case LEFT:
      steppingXY(stepX, 0);
      break;
    case RIGHT:
      steppingXY(-stepX, 0);
      break;
    }
    repaint();
  }
}





Canvas.setCommandListener(CommandListener l)

 

/* License
 * 
 * Copyright 1994-2004 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *  
 *  * Redistribution of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 * 
 *  * Redistribution in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 * 
 * Neither the name of Sun Microsystems, Inc. or the names of contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 *  
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *  
 * You acknowledge that this software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of any
 * nuclear facility. 
 */
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.midlet.MIDlet;
public class EventEx3 extends MIDlet {
  Display display;
  Command exit;
  public EventEx3() {
    display = Display.getDisplay(this);
  }
  public void destroyApp(boolean unconditional) {
  }
  public void pauseApp() {
    System.out.println("App paused.");
  }
  public void startApp() {
    display = Display.getDisplay(this);
    Canvas canvas = new Canvas() { // anonymous class
      public void paint(Graphics g) {
      }
      protected void keyPressed(int keyCode) {
        if (keyCode > 0) {
          System.out.println("keyPressed " + ((char) keyCode));
        } else {
          System.out.println("keyPressed action " + getGameAction(keyCode));
        }
      }
      protected void keyReleased(int keyCode) {
        if (keyCode > 0) {
          System.out.println("keyReleased " + ((char) keyCode));
        } else {
          System.out.println("keyReleased action " + getGameAction(keyCode));
        }
      }
    }; // end of anonymous class
    exit = new Command("Exit", Command.STOP, 1);
    canvas.addCommand(exit);
    canvas.setCommandListener(new CommandListener() {
      public void commandAction(Command c, Displayable d) {
        if (c == exit) {
          notifyDestroyed();
        } else {
          System.out.println("Saw the command: " + c);
        }
      }
    });
    display.setCurrent(canvas);
  }
}





Canvas.UP

 
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.midlet.MIDlet;
public class Navigate2MIDlet extends MIDlet implements CommandListener {
  private Command exitCommand;
  Displayable nd;
  Image image = null;
  public Navigate2MIDlet() {
    try {
      image = Image.createImage("/J.png");
    } catch (Exception e) {
    }
    Display display = Display.getDisplay(this);
    nd = new Navigate2Canvas(image);
    exitCommand = new Command("exit", Command.EXIT, 1);
    nd.addCommand(exitCommand);
    nd.setCommandListener(this);
    display.setCurrent(nd);
  }
  public void startApp() {
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command c, Displayable s) {
    notifyDestroyed();
  }
}
class Navigate2Canvas extends Canvas {
  private Image image;
  private int newX = 0;
  private int newY = 0;
  private int stepX = 0;
  private int stepY = 0;
  public Navigate2Canvas(Image image) {
    this.image = image;
    newX = 0;
    newY = 0;
    stepX = getWidth() / 4;
    stepY = getHeight() / 4;
  }
  public void steppingXY(int x, int y) {
    newX += x;
    newY += y;
  }
  public void paint(Graphics g) {
    int width = this.getWidth();
    int height = this.getHeight();
    g.setGrayScale(255);
    g.fillRect(0, 0, width - 1, height - 1);
    g.setGrayScale(0);
    g.drawRect(0, 0, width - 1, height - 1);
    g.translate(newX, newY);
    g.drawImage(image, 0, 0, g.TOP | g.LEFT);
  }
  protected void keyPressed(int keyCode) {
    int gameaction = getGameAction(keyCode);
    switch (gameaction) {
    case UP:
      steppingXY(0, stepY);
      break;
    case DOWN:
      steppingXY(0, -stepY);
      break;
    case LEFT:
      steppingXY(stepX, 0);
      break;
    case RIGHT:
      steppingXY(-stepX, 0);
      break;
    }
    repaint();
  }
}





extends Canvas

 
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.midlet.MIDlet;
public class TextAnchorMIDlet extends MIDlet implements CommandListener {
  private Command exitCommand;
  Display display;
  public void startApp() {
    Display display = Display.getDisplay(this);
    Displayable d = new TextAnchorCanvas();
    exitCommand = new Command("exit", Command.EXIT, 1);
    d.addCommand(exitCommand);
    d.setCommandListener(this);
    display.setCurrent(d);
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command c, Displayable s) {
    notifyDestroyed();
  }
}
class TextAnchorCanvas extends Canvas {
  int width = 0;
  int height = 0;
  public void paint(Graphics g) {
    width = getWidth();
    height = getHeight();
    g.setGrayScale(255);
    g.fillRect(0, 0, width - 1, height - 1);
    g.setGrayScale(0);
    g.drawRect(0, 0, width - 1, height - 1);
    g.drawString("TEXT", width / 2, height / 2, Graphics.BASELINE | Graphics.HCENTER);
  }
}


Источник — «http://jexp.ru/index.php?title=Java_by_API/javax.microedition.lcdui/Canvas&oldid=2716»