Java Tutorial/J2ME/Image

Display big Image

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;
import javax.microedition.midlet.MIDletStateChangeException;
public class DisplayBigImageTest extends MIDlet implements CommandListener {
  private Display display;
  private TestCanvas tc;
  private Command leftCommand = new Command("Left", Command.SCREEN, 1);
  private Command rightCommand = new Command("Right", Command.SCREEN, 1);
  public DisplayBigImageTest() {
    Image img = null;
    try {
      img = Image.createImage("/10.png");
    } catch (Exception e) {
      System.out.println(e.getMessage());
    }
    tc = new TestCanvas(img);
    tc.addCommand(rightCommand);
    tc.addCommand(leftCommand);
    tc.setCommandListener(this);
    display = Display.getDisplay(this);
  }
  public void startApp() throws MIDletStateChangeException {
    display.setCurrent(tc);
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command c, Displayable d) {
    int stepX = tc.getWidth() / 4;
    int stepY = tc.getHeight() / 4;
    if (d == tc && c == leftCommand) {
      tc.increaseXY(stepX, 0);
      tc.repaint();
    } else if (d == tc && c == rightCommand) {
      tc.increaseXY(-stepX, 0);
      tc.repaint();
    }
  }
  class TestCanvas extends Canvas {
    private Image img;
    private int transX = 0;
    private int transY = 0;
    public TestCanvas(Image img) {
      this.img = img;
      transX = 0;
      transY = 0;
    }
    public void increaseXY(int x, int y) {
      transX += x;
      transY += 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(transX, transY);
      g.drawImage(img, 0, 0, g.TOP | g.LEFT);
    }
  }
}

Draw image

import java.io.IOException;
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.midlet.MIDlet;
public class DrawImageGraphicsMIDlet extends MIDlet {
  private Display display;
  protected void startApp() {
    Canvas canvas = new LineCanvas();
    display = Display.getDisplay(this);
    display.setCurrent(canvas);
  }
  protected void pauseApp() {
  }
  protected void destroyApp(boolean unconditional) {
  }
}
class LineCanvas extends Canvas {
  public void paint(Graphics g) {
    int width = getWidth();
    int height = getHeight();
    try {
      Image image = Image.createImage("/h.png");
      g.drawImage(image, 0, 0, Graphics.TOP | Graphics.LEFT);
    } catch (IOException ex) {
      g.setColor(0xffffff);
      g.drawString("Failed to load image!", 0, 0, Graphics.TOP | Graphics.LEFT);
      return;
    }
  }
}

Draw image to the bottom and right

import java.io.IOException;
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.midlet.MIDlet;
public class ImageBottomRightGraphicsMIDlet extends MIDlet {
  private Display display;
  protected void startApp() {
    Canvas canvas = new LineCanvas();
    display = Display.getDisplay(this);
    display.setCurrent(canvas);
  }
  protected void pauseApp() {
  }
  protected void destroyApp(boolean unconditional) {
  }
}
class LineCanvas extends Canvas {
  public void paint(Graphics g) {
    int width = getWidth();
    int height = getHeight();
    try {
      Image image = Image.createImage("/h.png");
      g.drawImage(image, width, height, Graphics.BOTTOM | Graphics.RIGHT);
    } catch (IOException ex) {
      g.setColor(0xffffff);
      g.drawString("Failed to load image!", 0, 0, Graphics.TOP | Graphics.LEFT);
      return;
    }
  }
}

Draw image to the center vertically and horizontally

import java.io.IOException;
import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.midlet.MIDlet;
public class ImageVerticalHorizontalGraphicsMIDlet extends MIDlet {
  private Display display;
  protected void startApp() {
    Canvas canvas = new LineCanvas();
    display = Display.getDisplay(this);
    display.setCurrent(canvas);
  }
  protected void pauseApp() {
  }
  protected void destroyApp(boolean unconditional) {
  }
}
class LineCanvas extends Canvas {
  public void paint(Graphics g) {
    int width = getWidth();
    int height = getHeight();
    try {
      Image image = Image.createImage("/h.png");
      g.drawImage(image, width/2, height/2, Graphics.VCENTER | Graphics.HCENTER);
    } catch (IOException ex) {
      g.setColor(0xffffff);
      g.drawString("Failed to load image!", 0, 0, Graphics.TOP | Graphics.LEFT);
      return;
    }
  }
}

Draw image with rectangle

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 DrawImageMIDlet extends MIDlet implements CommandListener {
  private Command exitCommand;
  Display display;
  Image image = null;
  public void startApp() {
    Display display = Display.getDisplay(this);
    try {
      image = Image.createImage("/0.png");
    } catch (Exception e) {
    }
    Displayable d = new DrawImageCanvas(image);
    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 DrawImageCanvas extends Canvas {
  int width = 0;
  int height = 0;
  Image image = null;
  DrawImageCanvas(Image image) {
    this.image = image;
  }
  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.drawImage(image, width / 2, height / 2, g.HCENTER | g.VCENTER);
  }
}

Image loading exception

import javax.microedition.lcdui.Alert;
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 J2MEImmutableImageExample extends MIDlet {
  private Display display;
  private MyCanvas canvas;
  public J2MEImmutableImageExample() {
    display = Display.getDisplay(this);
    canvas = new MyCanvas(this);
  }
  protected void startApp() {
    display.setCurrent(canvas);
  }
  protected void pauseApp() {
  }
  protected void destroyApp(boolean unconditional) {
  }
  public void exitMIDlet() {
    destroyApp(true);
    notifyDestroyed();
  }
  class MyCanvas extends Canvas implements CommandListener {
    private Command exit;
    private J2MEImmutableImageExample immutableImageExample;
    private Image image = null;
    public MyCanvas(J2MEImmutableImageExample immutableImageExample) {
      this.immutableImageExample = immutableImageExample;
      exit = new Command("Exit", Command.EXIT, 1);
      addCommand(exit);
      setCommandListener(this);
      try {
        image = Image.createImage("/myImage.png");
      } catch (Exception error) {
        Alert alert = new Alert("Failure", "Can�t open image file.", null, null);
        alert.setTimeout(Alert.FOREVER);
        display.setCurrent(alert);
      }
    }
    protected void paint(Graphics graphics) {
      if (image != null) {
        graphics.drawImage(image, 0, 0, Graphics.VCENTER | Graphics.HCENTER);
      }
    }
    public void commandAction(Command command, Displayable display) {
      if (command == exit) {
        immutableImageExample.exitMIDlet();
      }
    }
  }
}

Immutable image

import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
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.Image;
import javax.microedition.lcdui.ImageItem;
import javax.microedition.midlet.MIDlet;
public class J2MEImmutableImage extends MIDlet implements CommandListener {
  private Display display;
  private Form form;
  private Command exit;
  private Image image;
  private ImageItem imageItem;
  public J2MEImmutableImage() {
    display = Display.getDisplay(this);
    exit = new Command("Exit", Command.EXIT, 1);
    form = new Form("Immutable Image Example");
    form.addCommand(exit);
    form.setCommandListener(this);
    try {
      image = Image.createImage("myimage.png");
      imageItem = new ImageItem(null, image, ImageItem.LAYOUT_NEWLINE_BEFORE
          | ImageItem.LAYOUT_LEFT | ImageItem.LAYOUT_NEWLINE_AFTER, "My Image");
      form.append(imageItem);
    } catch (java.io.IOException error) {
      Alert alert = new Alert("Error", "Cannot load myimage.png.", null, null);
      alert.setTimeout(Alert.FOREVER);
      alert.setType(AlertType.ERROR);
      display.setCurrent(alert);
    }
  }
  public void startApp() {
    display.setCurrent(form);
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command command, Displayable Displayable) {
    if (command == exit) {
      destroyApp(false);
      notifyDestroyed();
    }
  }
}

Mutable Image

import javax.microedition.lcdui.Alert;
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 J2MEMutableImageExample extends MIDlet {
  private Display display;
  private MyCanvas canvas;
  public J2MEMutableImageExample() {
    display = Display.getDisplay(this);
    canvas = new MyCanvas(this);
  }
  protected void startApp() {
    display.setCurrent(canvas);
  }
  protected void pauseApp() {
  }
  protected void destroyApp(boolean unconditional) {
  }
  public void exitMIDlet() {
    destroyApp(true);
    notifyDestroyed();
  }
  class MyCanvas extends Canvas implements CommandListener {
    private Command exit;
    private J2MEMutableImageExample mutableImageExample;
    private Image image = null;
    public MyCanvas(J2MEMutableImageExample mutableImageExample) {
      this.mutableImageExample = mutableImageExample;
      exit = new Command("Exit", Command.EXIT, 1);
      addCommand(exit);
      setCommandListener(this);
      try {
        image = Image.createImage(70, 70);
        Graphics graphics = image.getGraphics();
        graphics.setColor(255, 0, 0);
        graphics.fillArc(10, 10, 60, 50, 180, 180);
      } catch (Exception error) {
        Alert alert = new Alert("Failure", "Creating Image", null, null);
        alert.setTimeout(Alert.FOREVER);
        display.setCurrent(alert);
      }
    }
    protected void paint(Graphics graphics) {
      if (image != null) {
        graphics.setColor(255, 255, 255);
        graphics.fillRect(0, 0, getWidth(), getHeight());
        graphics.drawImage(image, 30, 30, Graphics.VCENTER | Graphics.HCENTER);
      }
    }
    public void commandAction(Command command, Displayable display) {
      if (command == exit) {
        mutableImageExample.exitMIDlet();
      }
    }
  }
}