Converting application to MVC architecture
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by terence6
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Published on 2010-06-13T18:09:24Z
Indexed on
2010/06/13
18:32 UTC
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I'm practicing writing MVC applications. I have a Mastermind game, that I would like to rewrite as MVC app. I have divided my code to parts, but instead of working game I'm getting empty Frame and an error in "public void paint( Graphics g )". Error comes from calling this method in my view with null argument. But how to overcome this ? MVC was quite simple with swing but awt and it's paint methods are much more complicated.
Code of working app :
http://paste.pocoo.org/show/224982/
App divided to MVC :
Main :
public class Main {
public static void main(String[] args){
Model model = new Model();
View view = new View("Mastermind", 400, 590, model);
Controller controller = new Controller(model, view);
view.setVisible(true);
}
}
Controller :
import java.awt.*;
import java.awt.event.*;
public class Controller implements MouseListener, ActionListener {
private Model model;
private View view;
public Controller(Model m, View v){
model = m;
view = v;
view.addWindowListener( new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);
} });
view.addMouseListener(this);
}
public void actionPerformed( ActionEvent e ) {
if(e.getSource() == view.checkAnswer){
if(model.isRowFull){
model.check();
}
}
}
public void mousePressed(MouseEvent e) {
Point mouse = new Point();
mouse = e.getPoint();
if (model.isPlaying){
if (mouse.x > 350) {
int button = 1 + (int)((mouse.y - 32) / 50);
if ((button >= 1) && (button <= 5)){
model.fillHole(button);
}
}
}
}
public void mouseClicked(MouseEvent e) {}
public void mouseReleased(MouseEvent e){}
public void mouseEntered(MouseEvent e) {}
public void mouseExited(MouseEvent e) {}
}
View :
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class View extends Frame implements ActionListener {
Model model;
JButton checkAnswer;
private JPanel button;
static final int HIT_X[] = {270,290,310,290,310}, HIT_Y[] = {506,496,496,516,516};
public View(String name, int w, int h, Model m){
model = m;
setTitle( name );
setSize( w,h );
setResizable( false );
this.setLayout(new BorderLayout());
button = new JPanel();
button.setSize( new Dimension(400, 100));
button.setVisible(true);
checkAnswer = new JButton("Check");
checkAnswer.addActionListener(this);
checkAnswer.setSize( new Dimension(200, 30));
button.add( checkAnswer );
this.add( button, BorderLayout.SOUTH);
button.setVisible(true);
for ( int i=0; i < model.SCORE; i++ ){
for ( int j = 0; j < model.LINE; j++ ){
model.pins[i][j] = new Pin(20,0);
model.pins[i][j].setPosition(j*50+30,510-i*50);
model.pins[i+model.SCORE][j] = new Pin(8,0);
model.pins[i+model.SCORE][j].setPosition(HIT_X[j],HIT_Y[j]-i*50);
}
}
for ( int i=0; i < model.LINE; i++ ){
model.pins[model.OPTIONS][i] = new Pin( 20, i+2 );
model.pins[model.OPTIONS][i].setPosition( 370,i * 50 + 56);
}
model.combination();
model.paint(null);
}
public void actionPerformed( ActionEvent e ) {
}
}
Model:
import java.awt.*;
public class Model extends Frame{
static final int
LINE = 5,
SCORE = 10, OPTIONS = 20;
Pin pins[][] = new Pin[21][LINE];
int combination[] = new int[LINE];
int curPin = 0;
int turn = 1;
int repaintPin;
boolean isUpdate = true, isPlaying = true, isRowFull = false;
public Model(){
}
void fillHole(int color) {
pins[turn-1][curPin].setColor(color+1);
repaintPins( turn );
curPin = (curPin+1) % LINE;
if (curPin == 0){
isRowFull = true;
}
}
public void paint( Graphics g ) {
g.setColor( new Color(238, 238, 238));
g.fillRect( 0,0,400,590);
for ( int i=0; i < pins.length; i++ ) {
pins[i][0].paint(g);
pins[i][1].paint(g);
pins[i][2].paint(g);
pins[i][3].paint(g);
pins[i][4].paint(g);
}
}
public void update( Graphics g ) {
if ( isUpdate ) {
paint(g);
}
else {
isUpdate = true;
pins[repaintPin-1][0].paint(g);
pins[repaintPin-1][1].paint(g);
pins[repaintPin-1][2].paint(g);
pins[repaintPin-1][3].paint(g);
pins[repaintPin-1][4].paint(g);
}
}
void repaintPins( int pin ) {
repaintPin = pin;
isUpdate = false;
repaint();
}
void check() {
int junkPegs[] = new int[LINE], junkCode[] = new int[LINE];
int pegCount = 0, pico = 0;
for ( int i = 0; i < LINE; i++ ) {
junkPegs[i] = pins[turn-1][i].getColor();
junkCode[i] = combination[i];
}
for ( int i = 0; i < LINE; i++ ){
if (junkPegs[i]==junkCode[i]) {
pins[turn+SCORE][pegCount].setColor(1);
pegCount++;
pico++;
junkPegs[i] = 98;
junkCode[i] = 99;
}
}
for ( int i = 0; i < LINE; i++ ){
for ( int j = 0; j < LINE; j++ )
if (junkPegs[i]==junkCode[j]) {
pins[turn+SCORE][pegCount].setColor(2);
pegCount++;
junkPegs[i] = 98;
junkCode[j] = 99;
j = LINE;
}
}
repaintPins( turn+SCORE );
if ( pico == LINE ){
isPlaying = false;
}
else if ( turn >= 10 ){
isPlaying = false;
}
else{
curPin = 0;
isRowFull = false;
turn++;
}
}
void combination() {
for ( int i = 0; i < LINE; i++ ){
combination[i] = 1 + (int)(Math.random()*5);
System.out.print(i+",");
}
}
}
class Pin{
private int color, X, Y, radius;
private static final Color COLORS[] = {
Color.black,
Color.white,
Color.red,
Color.yellow,
Color.green,
Color.blue,
new Color(7, 254, 250)};
public Pin(){
X = 0; Y = 0; radius = 0; color = 0;
}
public Pin( int r,int c ){
X = 0; Y = 0; radius = r; color = c;
}
public void paint( Graphics g ){
int x = X-radius;
int y = Y-radius;
if (color > 0){
g.setColor( COLORS[color]);
g.fillOval( x,y,2*radius,2*radius );
}
else{
g.setColor( new Color(238, 238, 238) );
g.drawOval( x,y,2*radius-1,2*radius-1 );
}
g.setColor( Color.black );
g.drawOval( x,y,2*radius,2*radius );
}
public void setPosition( int x,int y ){
this.X = x ;
this.Y = y ;
}
public void setColor( int c ){
color = c;
}
public int getColor() {
return color;
}
}
Any clues on how to overcome this would be great. Have I divided my code improperly ?
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