Transferring JFrame to JPanel - java

I created a simple "elevator" program (it's still in the beginning stages) that goes up 1 floor when I click UP and vice versa.
I messed up pretty badly when I drew all my components into JFrame, and as expected, it flickers every time I click the button (repaints). I know the solution to be draw in the JPanel and put the said panel in the JFrame, but I have a problem translating my JFrame components into JPanel. I've tried extending JPanel, creating a JFrame object and then overriding the paintComponent() method and doing my drawing there, but when I compile it does not draw it at all. It only creates the frame.
Can anyone help me or give me tips on how to proceed "transferring" my programming from JFrame based to JPanel based? Thank you in advance!
My code is below:
import java.awt.*;
import javax.swing.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.Timer;
import java.math.*;
public class MyCanvas extends JFrame {
private int up = 0;
private int down = 0;
private int movefloorup = 0;
private int buildingType;//type of building (1 = Residential, 2 = Commercial)
private int totnumoffloors; //for the total number of floors
private int numofelevators; //for the number of elevators to be generated
private int floorlimit = 0; //to determine up until where the elevator will be moving
private int currenttime; //determine the time of the day the elevator is operating (1 = Morning, 2 = Lunch, 3 = Afternooon)
//For elevator resetting to bottom
private int rectX = 190;
private int switchmarker = 0;
//Lines and stuff
private int horizborder = 0;
private int bordercount = 0;
private class UpAction implements ActionListener //move the elevator up
{
public void actionPerformed(ActionEvent e)
{
if(movefloorup<780){
repaint();
up++;
movefloorup = movefloorup + 130;
//repaint();
}
else
{
switchmarker = 1;
movefloorup = 0;
repaint();
}
}
}
private class DownAction implements ActionListener //move the elevator down
{
public void actionPerformed(ActionEvent e)
{
if(movefloorup>0){
repaint();
down++;
movefloorup = movefloorup - 130;
//repaint();
}
else
{
switchmarker = 0;
movefloorup = 780;
repaint();
}
}
}
public MyCanvas(int buildingType, int totnumoffloors, int numofelevators, int currenttime){
this.buildingType = buildingType;
this.totnumoffloors = totnumoffloors;
this.numofelevators = numofelevators;
this.currenttime = currenttime;
String title;
if(this.buildingType == 1)
{
title = "Residential Building";
}
else
{
title = "Commercial Building";
}
setLayout(null);
horizborder = 500*((int)Math.ceil((double)totnumoffloors/7)); //calculating how wide the window should be
bordercount = ((int)Math.ceil((double)totnumoffloors/7)); //counts how many borders there will be
//NOTES
//A floor is 130 units in the Y-Direction
//Drawing the bulding layout
if(totnumoffloors>7)
{
setSize(horizborder, 1000);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle(title);
setLayout(new BorderLayout());
getContentPane().setBackground(Color.WHITE);
}
else{
setSize(500, 1000); //suitable for 7 floors
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle(title);
setLayout(new BorderLayout());
getContentPane().setBackground(Color.WHITE);
}
JButton upButton = new JButton("UP");
upButton.addActionListener(new UpAction());
add(upButton, BorderLayout.NORTH);
JButton downButton = new JButton("DOWN");
//downButton.setBounds(0, 0, 220, 30);
//downButton.setLocation(100, 100);
downButton.addActionListener(new DownAction());
add(downButton, BorderLayout.SOUTH);
}
public void paint(Graphics graphics){ //this is where you draw shit
super.paint(graphics);
//Floors
graphics.setColor(Color.RED);
int numoffloorsY = 830;
int numoffloorsX = 830;
int floorbeginning = 0;
int floorcounter = 1;
int floorflag = 0;
int rightedge = 500;
if(this.totnumoffloors>7) //drawing the floors
{
//Default number of floors -> 7
for(int i = 0;i<totnumoffloors;i++)
{
graphics.setColor(Color.RED);
graphics.drawLine(floorbeginning,numoffloorsX,rightedge,numoffloorsY); //FLOORS
graphics.setColor(Color.DARK_GRAY);
graphics.setFont(new Font("TimesRoman", Font.PLAIN, 15));
graphics.drawString(" "+floorcounter, floorbeginning+10, numoffloorsY+20); //SAVE THIS FOR DRAWING FLOORS
numoffloorsY = numoffloorsY - 130;
numoffloorsX = numoffloorsX - 130;
floorcounter++;
floorflag++;
if(floorflag==7)
{
floorbeginning = floorbeginning + 500;
rightedge = rightedge+500;
numoffloorsY = 830;
numoffloorsX = 830;
floorflag = 0;
}
}
//Every other floor past 7 will be added here.
/*for(int i = 0;i<totnumoffloors-7;i++)
{
//System.out.println("LOLOOLO");
graphics.setColor(Color.RED);
graphics.drawLine(floorbeginning,numoffloorsX,horizborder,numoffloorsY);
graphics.setColor(Color.DARK_GRAY);
graphics.setFont(new Font("TimesRoman", Font.PLAIN, 15));
graphics.drawString(" "+floorcounter, floorbeginning, numoffloorsY+20);
//graphics.setColor(Color.DARK_GRAY);
//graphics.drawLine(500,0,500,1000);
floorcounter++;
numoffloorsY = numoffloorsY - 130;
numoffloorsX = numoffloorsX - 130;
}*/
//DIVIDING LINE -> to determine the first 7 floors from the ones higher up.
for(int i=0;i<bordercount;i++)
{
graphics.setColor(Color.DARK_GRAY);
graphics.drawLine(500*i,0,500*i,1000);
}
}
else{
for(int i = 0;i<this.totnumoffloors;i++)
{
graphics.setColor(Color.RED);
graphics.drawLine(0,numoffloorsX,500,numoffloorsY);
graphics.setColor(Color.DARK_GRAY);
graphics.setFont(new Font("TimesRoman", Font.PLAIN, 15));
graphics.drawString(" "+floorcounter, floorbeginning+10, numoffloorsY+20); //SAVE THIS FOR DRAWING FLOOR
numoffloorsY = numoffloorsY - 130;
numoffloorsX = numoffloorsX - 130;
floorcounter++;
}
}
//Drawing the elevators
if(up>0 && movefloorup<1000){
graphics.setColor(Color.GRAY);
if(switchmarker==1)
{
System.out.println("ELSA");
rectX = 690;
//rectX = rectX + 190;
}
else
{
rectX = 190;
}
System.out.println(rectX);
graphics.fillRect(rectX, 850-movefloorup, 100, 100); //this needs to match the stats of the rectangle to fill it properly
graphics.drawRect(rectX, 850-movefloorup, 100, 100);
//Line for the door
graphics.setColor(Color.BLACK);
graphics.drawLine(rectX+50, 850-movefloorup, rectX+50, 950-movefloorup); //match the y-coordinate for the rectangle, add 100 for the y-coordinate of the other end
System.out.println(movefloorup);
System.out.println(switchmarker);
//drawLine(x1, y1, x2, y2); --From (x1,y1) to (x2,y2)
}
else if(down>0 && movefloorup>0)
{
graphics.setColor(Color.GRAY);
if(switchmarker==1) //This determines when the elevator should move to the next column of higher floors.
{
System.out.println("ELSA");
rectX = 500;
}
System.out.println(rectX);
graphics.fillRect(rectX, 850-movefloorup, 100, 100); //this needs to match the stats of the rectangle to fill it properly
//graphics.drawRect(190, 850 + movefloorup, 100, 100); //FIRST FLOOR
graphics.drawRect(rectX, 850-movefloorup, 100, 100); //SECOND FLOOR (135 units difference in Y-axis between floors)
//x-coordinate, y-coordinate, width, height
//Line for the door
graphics.setColor(Color.BLACK);
graphics.drawLine(rectX+50, 850-movefloorup, rectX+50, 950-movefloorup); //match the y-coordinate for the rectangle, add 100 for the y-coordinate of the other end
System.out.println(movefloorup);
System.out.println(switchmarker);
}
else
{
graphics.setColor(Color.GRAY);
graphics.fillRect(190, 850, 100, 100); //this needs to match the stats of the rectangle to fill it properly
graphics.drawRect(190, 850, 100, 100); //FIRST FLOOR
graphics.drawRect(190, 850, 100, 100); //SECOND FLOOR (135 units difference in Y-axis between floors)
//x-coordinate, y-coordinate, width, height
//Line for the door
graphics.setColor(Color.BLACK);
graphics.drawLine(240, 850, 240, 950); //match the y-coordinate for the rectangle, add 100 for the y-coordinate of the other end
//System.out.println("In else!");
}
}
}
The main class just gets input from the user, such as the number of floors, time of day, etc.

This is going to be a little messy.
Start by creating a custom component that extends from JPanel (I'll call it ElevatorPane).
Take the contents of the current paint method and place them within this components paintComponent method. This will involve moving the instance variables that the paintComponent method will need including, totnumoffloors, bordercount, up, down, movefloorup, switchmarker, rectX
This is where it gets a little messy...
You need to take the contents of your ActionListeners and translate these into methods within the ElevatorPane, this way you expose the functionality without exposing the details...
Create a constructor within ElevatorPane that takes the number of floors.
Override the getPrefferedSize method of ElevatorPane and return the size that the component needs to be to satisfy your needs...
Create an instance field of ElevatorPane in MyCanvas, instantiate it and add it to the frame.
Clean, build, run...

Related

How to prevent my KeyEvent from repainting both objects?

I am working on a simple game which requires 1 player (the square) and some enemies that spawn randomly inside the play-area. I am running into an issue currently, because when I run my program, pressing any arrow key will repaint not only the player's new location, but it will also re-spawn all the enemies into the new locations.
I have gone through my code a few times and I am still stumped as to why this is happening. Any help would be greatly appreciated.
P.S. I am not a very experienced programmer, so some of this code may not be as efficient as possible and some things may be incorrect; feel free to point out any errors besides the issue at hand. Thanks!
Main Class
public class Eat {
public static void main(String[] args) {
// Creating the main frame
JFrame main = new JFrame("Eat 'Em All - Version 1.0.2");
main.setSize(497, 599);
main.setLocationRelativeTo(null);
main.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
main.setResizable(false);
// Colours and borders
Border areaBorder = new LineBorder(Color.LIGHT_GRAY, 3);
// Creating main JPanel
JPanel area = new JPanel();
area.setLayout(new BoxLayout(area, BoxLayout.PAGE_AXIS));
area.setBackground(Color.WHITE);
main.setContentPane(area);
// Creating the drawing/image/player
DrawPlayer player = new DrawPlayer();
player.setPreferredSize(new Dimension(497, 539));
player.setOpaque(false);
// Enemies
DrawEnemy enemy = new DrawEnemy();
enemy.setPreferredSize(new Dimension(497, 539));
enemy.setBackground(Color.WHITE);
// Creating the control panel for buttons, etc
JPanel control = new JPanel();
control.setPreferredSize(new Dimension(497, 60));
control.setLayout(new GridLayout(1, 2, 0, 0));
control.setBorder(areaBorder);
JLabel welcome = new JLabel(" Welcome to Eat 'Em All |--| Press 'Start'");
JButton start = new JButton("Start");
// Adding it all to the frame
main.add(enemy);
enemy.add(player);
control.add(welcome);
control.add(start);
area.add(control);
// Adding keylistener and making button false
player.addKeyListener(player);
player.setFocusable(true);
start.setFocusable(false);
enemy.setFocusable(false);
// Bring frame to front and visible
main.toFront();
main.setVisible(true);
System.out.println(player.getWidth() / 2);
System.out.println(player.getHeight() / 2);
}
}
Drawing Player Class
public class DrawPlayer extends JPanel implements KeyListener {
long xPosition = 0;
long yPosition = 0;
public void paintComponent(Graphics g) {
super.paintComponent(g);
// Making loop to get points and move it
// Center of area is x: 245 y: 255
int xPoints[] = {235, 255, 255, 235, 235, 255};
int yPoints[] = {265, 265, 245, 245, 265, 245};
for (int i = 0; i < xPoints.length; i++) {
xPoints[i] += xPosition;
yPoints[i] += yPosition;
}
g.setColor(Color.BLUE);
g.drawPolygon(xPoints, yPoints, xPoints.length);
}
public void keyPressed(KeyEvent e) {
switch (e.getKeyCode()) {
case KeyEvent.VK_DOWN:
if (yPosition == 245) {
yPosition -= 5;
} else {
yPosition += 5;
}
break;
case KeyEvent.VK_UP:
if (yPosition == -245) {
yPosition += 5;
} else {
yPosition -= 5;
}
break;
case KeyEvent.VK_LEFT:
if (xPosition == -235) {
xPosition += 5;
} else {
xPosition -= 5;
}
break;
case KeyEvent.VK_RIGHT:
if (xPosition == 235) {
xPosition -= 5;
} else {
xPosition += 5;
}
break;
}
repaint();
}
public void keyReleased(KeyEvent e) {
}
public void keyTyped(KeyEvent e) {
}
}
Drawing Enemies Class
public class DrawEnemy extends JPanel {
public void paintComponent(Graphics f) {
super.paintComponent(f);
for (int i = 0; i < 10; i++ ){
f.setColor(Color.RED);
f.drawOval((int)(Math.random() * ((440 - 0) + 0) + 0), (int)(Math.random() * ((500 - 0) + 0) + 0), 50, 50);
}
}
}
Your have a problem here:
public void paintComponent(Graphics f) {
super.paintComponent(f);
for (int i = 0; i < 10; i++ ){
f.setColor(Color.RED);
f.drawOval((int)(Math.random() * ((440 - 0) + 0) + 0), (int)(Math.random() * ((500 - 0) + 0) + 0), 50, 50);
}
}
You've got program logic inside of a painting method, something you should never do, since you never have full control over when or even if a painting method will be called. The solution, get the randomization out of the paintComponent method and into its own separate method, one that you call if and only if you want to randomize the enemies, and not every time you repaint.
Other issues:
Separate your program logic from your GUI.
For instance you should have a non-GUI Enemy class, one that has fields for its own position, its size, its movement, perhaps a move() method, perhaps a collision(Player p) method.
You should have only one JPanel that does drawing and this should be its only job.
Again, you don't tie movement of anything to the painting method.
You would want a game loop of some sort, perhaps a Swing Timer. This will generate regularly spaced ticks that will prod Enemies and Players to move.
Get rid of KeyListener code and favor Key Bindings. The latter is much less kludgy when it comes to component focus. Do check the tutorial for this.

Java | ActionListeners in two JButtons, no response

I've been stuck at this for a couple of days now (first time working with multiple ActionListener, so bear with me).
I have two buttons, with each an actionlistener for moving a drawing to either the left or the right.
Yet either the actionlisteners do not seem to work properly, or the actionperformed does not work.
Suggestions are much appreciated, I've tried switching them to Action as was suggested elsewhere on this forum, but that didn't work out either.
package h03verplaatsbarebal;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Paneel extends JPanel implements ActionListener{
//declare objects
private JButton knopLinks; // moves ball to left
private JButton knopRechts; // moves ball to right
//constants
private int horizontalePlaats; // variabele voor horizontale plaats
private int VERPLAATSING; // constante voor verplaatsing
/*create panel with 2 buttons (to left, to right) and a ball*/
public Paneel() {
//create objects
knopLinks = new JButton ("Naar links");
knopLinks.addActionListener(this);
knopRechts = new JButton ("Naar rechts");
knopRechts.addActionListener(this);
//Tooltips
knopLinks.setToolTipText("Klik hier om de bal naar links te bewegen");
knopRechts.setToolTipText("Klik hier om de bal naar rechts te bewegen");
//add to window
add(knopLinks);
add(knopRechts);
}
public void paintComponent(Graphics g){
super.paintComponent(g);
int midden = getWidth() / 2; // halfway screen
int balDiameter = 50;
int ovaalDiameter = 25;
horizontalePlaats = midden;
//draw line
g.setColor(Color.GREEN);
g.drawLine(30, getHeight() - 30, getWidth() -30, getHeight() - 30); //lijn
//draw ball
g.setColor(Color.ORANGE);
g.fillOval(horizontalePlaats - balDiameter, getHeight() - 130, 100, 100); // oranje bal
g.setColor(Color.BLACK);
g.drawOval(horizontalePlaats - balDiameter, getHeight() - 130, 100, 100); //lijn van bal
g.setColor(Color.BLACK);
g.drawOval(horizontalePlaats - ovaalDiameter, getHeight() - 130, 50, 100); // binnen lijnen
}
/*clicking buttons*/
public void actionPerformed(ActionEvent e) {
VERPLAATSING = 15;
if (e.getSource() == knopLinks){ //move to left
horizontalePlaats = horizontalePlaats - VERPLAATSING;
}
else { //move to right
horizontalePlaats = horizontalePlaats + VERPLAATSING;
}
repaint(); // paint again
}
}
Your action listener should work, but what it does is only modifying the value of horizontalePlaats .
The problem is that horizontalePlaats gets overwritten by the value of midden in paintComponent, so you never see the result of the performed actions.
horizontalePlaats = midden;
You are overriding horizontalePlaats in your paint.
int midden = getWidth() / 2; // halfway screen
int balDiameter = 50;
int ovaalDiameter = 25;
horizontalePlaats = midden;
I think your action listener is fine, but you need to only initialize horizontalePlaats to the middle.
You can move this
int midden = getWidth() / 2; // halfway screen
horizontalePlaats = midden;
to your Paneel constructor.

Mini Tennis Game using Threads Java

I am having a some difficulty with developing of my code. Since I am not too advanced with Java I need some help. I am trying to develop Mini Tennis game using Threads. The aim of this game is to catch the balls moving on the window with the paddle that can be controlled with the left and right buttons on the keyboard.
Those balls should move diagonally on the window and when they touch to any of the corner (out of bottom) they should change their ways like light reflection. Apart from this, when a ball touches to one of the obstacles they should change their ways as well.
Paddle on the bottom of the window can be controlled with left and right keys.The task of the player is to catch the balls. The number of balls that the user catches will be shown on the Score part with the total number of balls going to the bottom corner.
User may need to save the state of the game. When the user clicks to the “save game” button; ball locations and score should save to the file. And when the user clicks to the open button, the state of game should be reloaded.
My source code files are:
public class BallPanel extends JPanel implements Runnable {
int RED, GREEN, BLUE;
int Xdirection = 1, Ydirection = 1;
boolean pleaseWait = false;
BallPanel(int X, int Y){
locateBall(X, Y, 30, 30);
/* Random r = new Random();
RED = r.nextInt(255);
GREEN = r.nextInt(255);
BLUE = r.nextInt(255);
*/
}
public void paint(Graphics g){
int panelWidth = this.getWidth();
int panelHeight = this.getHeight();
// g.setColor( new Color(RED, GREEN, BLUE ));
g.setColor(Color.ORANGE);
g.fillOval(panelWidth/2, panelHeight/2,panelWidth/2, panelHeight/2);
}
public void locateBall(int x, int y, int width, int height){
setBounds(x, y, width, height);
repaint();
}
public void run() {
int width = this.getWidth();
int height = this.getHeight();
Random r = new Random();
while(true){
if(!pleaseWait){
int lastX = this.getX();
int lastY = this.getY();
if (lastX > 675) Xdirection = -1;
if (lastY > 485) Ydirection = -1;
if (lastX < -5) Xdirection = 1;
if (lastY < -5) Ydirection = 1;
/* if(lastX > 280 && lastY > 170){
Xdirection = -1;
Ydirection = -1;
}
*/
locateBall(lastX + Xdirection*r.nextInt(3),
lastY + Ydirection*r.nextInt(3),
width, height );
}
try{
Thread.sleep(5);
}catch(Exception e){};
}
}
}
public class BallWindow extends JFrame implements ActionListener{
JButton btnStop = new JButton("STOP");
JButton btnSave = new JButton("SAVE");
Vector<BallPanel> ballVector = new Vector<BallPanel>();
JPanel p1 = createPanel(280, 200, 200, 20, Color.gray);
JPanel p2 = createPanel(280, 300, 200, 20, Color.gray);
JPanel bottomp = createPanel(345, 540, 70, 15, Color.black);
JPanel lborder = createPanel(10, 10, 2, 560, Color.black);
JPanel rborder = createPanel(720, 10, 2, 560, Color.black);
JPanel tborder = createPanel(10, 10, 710, 2, Color.black);
public BallWindow() {
setLayout(null);
btnStop.setBounds(12, 15, 100, 30);
btnStop.addActionListener(this);
add(btnStop);
btnSave.setBounds(12, 50, 100, 30);
//btnSave.addActionListener(this);
add(btnSave);
Random r = new Random();
for(int i=0; i<7; i++){
BallPanel bp = new BallPanel(r.nextInt(740), r.nextInt(590));
Thread t = new Thread(bp);
ballVector.add(bp);
t.start();
add(bp);
}
add(p1);
add(p2);
add(bottomp);
add(lborder);
add(rborder);
add(tborder);
setSize(740, 590);
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setResizable(false);
repaint();
}
JPanel createPanel(int x, int y, int width, int height, Color pColor){
JPanel temp = new JPanel();
temp.setBackground(pColor);
temp.setBounds(x, y, width, height);
return temp;
}
public static void main(String[] args) {
new BallWindow();
}
public void actionPerformed(ActionEvent arg0) {
for (BallPanel ball : ballVector) {
ball.pleaseWait = !ball.pleaseWait;
}
if( btnStop.getText().equalsIgnoreCase("STOP"))
btnStop.setText("START");
else
btnStop.setText("STOP");
// if(arg0.getSource())
}
}
I'm stuck with obstacles part and the keylistener. Any type of help will be greatly appreciated.
Hava a look at http://zetcode.com/tutorials/javagamestutorial/
You should especially check out the Basics and the Animation section. It will help clean up the animation and thread stuff you are doing. It also shows a general pattern how one could implement a java game.

Zooming In On a Java Graphic

I am making a graph of a sound speed profile with java graphics. I have the static graph drawn (the one that pops up when you run the program), but I am trying to implement it such that if the user clicks on either the x or y axis, then it will zoom in so you can look at the sound speed profile more closely. I don't have the sound speed profile in the graph yet (I already know how to do that, I'm just saving the effort of drawing it until I have the zoom feature figured out). Does anyone have any ideas as to how to make this work? I have seen people trying to use the Affine Transform for similar tasks, but I am not sure that's the right thing to do or if I'm even doing this correctly. The particular code to look at is the paint(), zoomIn(), and mouseClicked() method. Ideas would be much apprecaited!
public class SoundSpeedProfile extends JPanel implements MouseListener, ActionListener {
private String title;
private String subTitle;
private JFrame frame;
private Graphics g;
.
.
.
/**Draws the sound speed profile and surrounding graphics
* #param Graphics g - graphics object
*/
public void paint(Graphics g){
this.g = g;
super.paint(g); //the super knows how to draw "standard" components like squares, rectangles, circles, etc
g.setColor(Color.DARK_GRAY);
//1) Set up the graph the sound speed profile lives in
//X-Axis for Speeds
g.drawLine(100, 150, 450, 150);//the graphics display has 0,0 in the upper left corner versus the lower left corner
int i = 120;
int k = 1460;
while (i<440){
g.drawString("|", i, 155);
g.drawString("" + k + "", i-2, 140);
k = k + 20;
i = i + 60;
}
//Y-Axis
g.drawLine(100, 500, 100, 150);
k= 7000;
int j = 500;
while (j>160){
g.drawString("" + k, 60, j);
g.drawString("--", 94, j);
k = k - 1000;
j = j - 50;
}
Font f1 = new Font("Serif", 4, 15);
g.setFont(f1);
g.drawString(this.title, 200,30);//Graph Title
g.drawString(this.subTitle, 225, 50);
Font f2 = new Font("Serif", 2, 15);
g.setFont(f2);
g.drawString("Sound Speed ", 200, 110);//x-axis label
g.drawString("(" + spdUnits + ")", 290, 110); //Units label--taken from input array
g.drawString("Depth", 10, 180); //y-axis label
g.drawString("(" + depUnits + ")", 07, 200); //Units label--taken from input array
//((Graphics2D)g).scale(20, 20);
}
/**Creates and shows the GUI drawing of the sound speed profile in a JFrame
*/
private void createAndShowGUI(){
frame = new JFrame("Sound Speed Profile");
canvas = new Canvas();
frame.add(canvas);
frame.addMouseListener(this);
frame.setBackground(Color.cyan);
frame.setSize(600,800);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setLayout(new BorderLayout());
frame.add(this, BorderLayout.CENTER);//add the sound speed profile graphic and set a Border Layout
//frame.pack();
frame.setVisible(true);
}
/**
* Runs test cases
* #param args
*/
public static void main (String [] args){
ssp.setTitle("Sound Speed Profile 1");
ssp.setSubtitle("June 1, 2012");
ssp.createAndShowGUI();
ssp.repaint(); //necessary?
}
#Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
}
#Override
public void mouseClicked(MouseEvent arg0) {
int x = arg0.getX();
//System.out.println("x: " + x);
int xMin = x - 50;
int xMax = x + 50;
int y = arg0.getY();
//System.out.println("y: " + y);
int yMin = y-50;
int yMax = y + 50;
//If the user clicked on the x-axis
if ( 160<y && y<180 && 100<x && x<450){
System.out.println("About to zoom in on the x-axis");
zoomIn(x, y);
//System.out.println("zooming in on the x-axis");
}
//If the user clicked on the y-axis
if (90<x && x<110 && 150 <y && y<500){
//System.out.println("zooming in on the y-axis");
}
}
public void zoomIn(int x, int y){
AffineTransform old = ((Graphics2D) g).getTransform();
for (double zoom = 1; zoom >=0.1; zoom=-0.1){
AffineTransform tr2 =AffineTransform.getTranslateInstance(-x, -y);
AffineTransform tr= AffineTransform.getScaleInstance(zoom,zoom);
tr.concatenate(tr2); tr2=tr;
tr =AffineTransform.getTranslateInstance(x, y);
tr.concatenate(tr2); tr2=tr;
tr= new AffineTransform(old);
tr.concatenate(tr2); tr2=tr;
((Graphics2D)g).setTransform(tr2);
((Graphics2D)g).drawRect(x, y, 10, 10);
((Graphics2D)g).setTransform(old);
}
}

Creating a Checkers Board in Java

I'm begining a little project to create a simple checkers game. However it's been a long time since I've used the java GUI tools. The goal of the code at this point is to draw the initial board (red pieces at top, black at bottom). However all I get when I run the code is a blank frame. I'm also a little uncertain if my circle drawing code will do what I want (ie create solid red or black circles inside certain squares) Here is the code. Thanks in advance for any help/suggestions
EDIT: I should probably alternate drawing blue and gray squares or else the thing will probably just be a giant blue blob, however I'll settle for a giant blue blob at this point :p
import javax.swing.*;
import java.awt.*;
public class CheckersServer
{
public static class Board
{
private JFrame frame = new JFrame();
private JPanel backBoard = new JPanel();
Board()
{
frame.setSize(905,905);
backBoard.setSize(900,900);
frame.setTitle("Checkers");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
backBoard.setVisible(true);
boardSquare bs;
String type = null;
//Filling in Red Side
for (int i = 0; i <=1; i++)
{
for(int j = 0; j < 9; j++)
{
if(j % 2 == 0)
{
type = "Red";
}
else
{
type = "Blank";
}
bs = new boardSquare(100*j,100*i,type);
backBoard.add(bs);
}
}
//Filling in empty middle
type = "Blank";
for (int i = 2; i < 7; i++)
{
for(int j = 0; j < 9; j++)
{
bs = new boardSquare(100*j,100*i,type);
backBoard.add(bs);
}
}
//Filling in Black side
for (int i = 7; i < 9; i++)
{
for(int j = 0; j < 9; j++)
{
if(j % 2 != 0)
{
type = "Black";
}
else
{
type = "Blank";
}
bs = new boardSquare(100*j,100*i,type);
backBoard.add(bs);
}
}
backBoard.repaint();
frame.add(backBoard);
frame.repaint();
}
private class boardSquare extends JComponent
{
private int x; //x position of the rectangle measured from top left corner
private int y; //y position of the rectangle measured from top left corner
private boolean isBlack = false;
private boolean isRed = false;
public boardSquare(int p, int q, String type)
{
x = p;
y = q;
if (type.equals("Black"))
{
isBlack = true;
isRed = false;
}
else if (type.equals("Red"))
{
isRed = true;
isBlack = false;
}
else if (type.equals("Blank"))
{
isBlack = false;
isRed = false;
}
}
public void paintComponent(Graphics g)
{
Graphics2D g2 = (Graphics2D) g;
Rectangle box = new Rectangle(x,y,100,100);
g2.draw(box);
g2.setPaint(Color.BLUE);
g2.fill(box);
if(isBlack)
{
g2.fillOval(x, y,100 ,100 );
g2.setColor(Color.black);
g2.drawOval(x, y, 100, 100);
}
else if(isRed)
{
g2.fillOval(x, y,100 ,100 );
g2.setColor(Color.red);
g2.drawOval(x, y, 100, 100);
}
}
}
}
public static void main(String[] args)
{
Board game = new Board();
}
}
You have several issues.
Java UI is layout-based, which means that when you add a component to a parent, the parent's layout determines where the child component will be placed. You don't have any code to set up the layout, and so your application is using the defaults (FlowLayout is the default, and this may work in your case, as long as your JFrame and children are the appropriate size).
The bigger problems are in your boardSquare class. By default, JPanels have a dimension of 10x10. You aren't specifying the size, and so all your squares are 10x10. You need to tell the squares how big they are. You can do this in the boardSquare constructor:
setPreferredSize(new Dimension(100, 100));
Finally, in your drawing code, you are doing an offset of x,y when drawing the squares and circles. This is an offset from the top-left corner of the component. Your components (after setting the size) will be 100x100 pixels. But if your x,y are greater than these values, you will be drawing outside of the bounds of the component. Instead, these values should be set to 0,0 because that is the top-left corner of the component you are drawing in.
By just setting the preferred size of the squares and setting x,y to 0, I was able to get the squares drawing in the frame, though it wasn't pretty. You will need to work on setting the correct layout before it will be laid out correctly.
Here are some hints:
Your BoardSquares have dimension 0x0. Not a good size for something you want to be visible to the user.
To help visualize what's going on, cause each BoardSquare to be 100x100 pixels in size, and give them a border. Now you can see where they are showing up in your GUI. Your GUI code still needs significant changes, but this will at least let you start seeing what you're dealing with.
public BoardSquare(int p, int q, String type)
{
this.setBorder(new LineBorder(Color.CYAN, 2));
this.setPreferredSize(new Dimension(100, 100));
// ... etc ...
BoardSquare seems to be coded to draw its contents based on coordinates from the absolute topmost leftmost point in the window, but they should be coded to draw themselves from the topmost leftmost point of the BoardSquare itself. That is, components should only draw within their own boundaries, and they should use coordinates that assume 0,0 designates the top,left of the component, not of the window.
If you want to use BoardSquares (JComponents) and add them to the frame, you probably should use a different layout manager, like GridLayout. FlowLayout won't give you the kind of precise positioning you want.
import javax.swing.*;
import javax.swing.border.LineBorder;
import java.awt.*;
public class CheckersServer2
{
public static String type_BLANK = "BLANK";
public static String type_RED = "RED";
public static String type_BLACK = "BLACK";
public static int width = 100;
public static int height = 100;
public static class Board
{
private JFrame frame = new JFrame();
private JPanel backBoard = new JPanel();
Board()
{
int numRows = 8;
int numCols = 8;
frame.setSize(905,905);
backBoard.setSize(900,900);
frame.setTitle("Checkers");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
backBoard.setVisible(true);
String type;
for(int r=0; r<numRows; r++){
for(int c=0; c<numCols; c++){
//
type = type_BLANK;
if(c%2==0){
if(r==0 || r==2) {
type = type_RED;
}else if(r==6){
type = type_BLACK;
}
}else{
if(r==1){
type = type_RED;
} else if(r==5 || r==7) {
type = type_BLACK;
}
}
backBoard.add(new BoardSquare(r,c,type));
}
}
backBoard.repaint();
frame.add(backBoard);
frame.repaint();
}
private class BoardSquare extends JComponent
{
/**
*
*/
private static final long serialVersionUID = 1L;
private int x; //x position of the rectangle measured from top left corner
private int y; //y position of the rectangle measured from top left corner
private boolean isBlack = false;
private boolean isRed = false;
public BoardSquare(int p, int q, String type)
{
//this.setBorder(new LineBorder(Color.CYAN, 2));
this.setPreferredSize(new Dimension(width, height));
x = p;
y = q;
if (type.equals(type_BLACK))
{
isBlack = true;
isRed = false;
}
else if (type.equals(type_RED))
{
isRed = true;
isBlack = false;
}
else if (type.equals(type_BLANK))
{
isBlack = false;
isRed = false;
}
}
public void paintComponent(Graphics g)
{
Graphics2D g2 = (Graphics2D) g;
Rectangle box = new Rectangle(x,y,width,height);
g2.draw(box);
g2.setPaint(Color.BLUE);
g2.fill(box);
int ovalWidth = width - 15;
int ovalHeight = ovalWidth;
if(isBlack)
{
g2.setColor(Color.black);
g2.fillOval(x, y, ovalWidth, ovalHeight);
g2.drawOval(x, y, ovalWidth, ovalHeight);
}
else if(isRed)
{
g2.setColor(Color.red);
g2.fillOval(x, y, ovalWidth, ovalHeight);
g2.drawOval(x, y, ovalWidth, ovalHeight);
}
}
}
}
public static void main(String[] args)
{
Board game = new Board();
}
}

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