Week3 - Canvas Responding Button Presses

I created this little app, where different sizes and degrees of color grey of square appear responding to certain button being pressed. For example, if button 1 is pressed, a square that is 1/10 of screen width wide and 1/10 of screen height high and very close to total black will appear. if button 9 is pressed, a square that is 9/10 of screen width wide and 9/10 of screen height high and less close to total black will appear.

Screen shots:
1. button 6 is pressed


2. button 4 is pressed

3. button 9 is pressed:

Source code:

import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.midlet.MIDlet;

public class CanvasResponding extends MIDlet implements CommandListener {

// The MIDlet's Display object
private Display display;

// Flag indicating first call of startApp
protected boolean started;

// Our Exit command
private Command exitCommand;

protected void startApp() {

//for debugging
System.out.println("I'm starting!!! - " + started);

if (!started) {
display = Display.getDisplay(this);
Canvas canvas = new KeyFinderCanvas();
exitCommand = new Command("Exit", Command.EXIT, 0);
canvas.addCommand(exitCommand);
canvas.setCommandListener(this);
display.setCurrent(canvas);

started = true;

System.out.println("Application Started! Yay! - " + started);
}
}

protected void pauseApp() {
}

protected void destroyApp(boolean unconditional) {
}

public void commandAction(Command c, Displayable d) {
if (c == exitCommand) {
// Exit. No need to call destroyApp
// because it is empty.
notifyDestroyed();
}
}
}

//KeyFinderCanvas is a separate canvas which displays keys and codes
class KeyFinderCanvas extends Canvas {

static int[] keyCodes = {KEY_NUM0, KEY_NUM1, KEY_NUM2, KEY_NUM3, KEY_NUM4,
KEY_NUM5, KEY_NUM6, KEY_NUM7, KEY_NUM8, KEY_NUM9,
KEY_POUND, KEY_STAR};
static String[] keyNames = {"KEY_NUM0", "KEY_NUM1", "KEY_NUM2", "KEY_NUM3", "KEY_NUM4",
"KEY_NUM5", "KEY_NUM6", "KEY_NUM7", "KEY_NUM8", "KEY_NUM9",
"KEY_POUND", "KEY_STAR"};

static int[] gameActions = {
UP, DOWN, LEFT, RIGHT, FIRE,
GAME_A, GAME_B, GAME_C, GAME_D};
static String[] gameNames = {
"UP", "DOWN", "LEFT", "RIGHT", "FIRE",
"GAME_A", "GAME_B", "GAME_C", "GAME_D" };


int lastKeyCode = 0;

int lastX;

int lastY;

boolean pointer;

protected void keyPressed(int keyCode) {
lastKeyCode = keyCode;
repaint();
}

protected void keyRepeated(int keyCode) {
lastKeyCode = keyCode;
repaint();
}

protected void keyReleased(int keyCode) {
lastKeyCode = 0;
repaint();
}

protected void pointerPressed(int x, int y) {
lastX = x;
lastY = y;
pointer = true;
repaint();
}

protected void pointerDragged(int x, int y) {
lastX = x;
lastY = y;
pointer = true;
repaint();
}

protected void pointerReleased(int x, int y) {
pointer = false;
repaint();
}

protected void paint(Graphics g) {
g.setColor(0xffffff);

//this is not smart, instead of doing this - what would you do?
g.fillRect(0, 0, getWidth(), getHeight());

g.setColor(0);
if (lastKeyCode != 0) {
String keyText = "";
String keyName = null;

// See if it is a standard key
for (int i = 0; i < keyCodes.length; i++) {
if (lastKeyCode == keyCodes[i]) {
//keyName = keyNames[i];
g.setColor(i * 0x111111);
g.fillRect(0, 0, getWidth()/10*i, getHeight()/10*i);
break;
}
}

if (keyName == null) {
// See if it is a game action
for (int i = 0; i < gameActions.length; i++) {
if (lastKeyCode == getKeyCode(gameActions[i])) {
//keyName = gameNames[i];
break;
}
}
}

g.drawString(keyText, getWidth()/2, getHeight()/2,
Graphics.BASELINE|Graphics.HCENTER);

if (keyName != null) {
g.drawString(keyName, getWidth()/2, getHeight()/2 + g.getFont().getHeight(),
Graphics.BASELINE|Graphics.HCENTER);
}
} else if (pointer) {
g.drawString("(" + lastX + ", " + lastY + ")", getWidth()/2, getHeight()/2,
Graphics.BASELINE|Graphics.HCENTER);
}
}
}