Canvas Paint method is not working with JLayeredPane - java

I've been trying to create two layered images within a JFrame using JLayeredPane however I'm not able to draw a shape using the paint() function within the Canvas class.
Here is what I wrote:
package com.baduk.main;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JLayeredPane;
import javax.swing.JPanel;
public class Game extends Canvas implements Runnable {
private ImageIcon icon;
private JLabel back;
private JLayeredPane layer;
/**
*
*/
private static final long serialVersionUID = -3441156857004256039L;
public Game() {
//Background image with depth 0
icon = new ImageIcon("C:/Users/scaraven/Downloads/baduk_board.png");
back = new JLabel(icon);
back.setBounds(0,0,icon.getIconWidth(),icon.getIconHeight());
//Create JFrame
JFrame frame = new JFrame("BADUK");
frame.setSize(new Dimension(icon.getIconWidth()+5,icon.getIconHeight()+25));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
frame.setLocationRelativeTo(null);
//Create JLayeredPane
layer = new JLayeredPane();
layer.add(back,new Integer(1));
layer.add(this,new Integer(0));
frame.setContentPane(layer);
frame.setVisible(true);
}
public static void main(String[] args) {
new Game();
}
#Override
public void run() {
// TODO Auto-generated method stub
}
public void paint(Graphics g) {
g.setColor(Color.black);
g.fillRect(10, 10, 100, 100);
}
}
According to what I wrote, A Jframe should be generated with an image as the background and a black rectangle on top, however I only get the image. Does anyone know what is wrong with the code I wrote and what I need to change?

Related

Image is not being confined to a direct area

Image is not being confined to a direct area in this java code below. I want the java image to be displayed in its entirety in a 400 width by 400 height image. I tried to do that by frame.setSize(400, 400); and it is not working. My code includes drawImage which is what I was told I had to put in the code for this to work. I don't what to do next.
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.WindowConstants;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
public class SwingSandbox {
public static void main(String[] args) throws IOException {
JFrame frame = buildFrame();
final BufferedImage image = ImageIO.read(new File("/Users/johnzalubski/Desktop/c.jpg"));
JPanel pane = new JPanel() {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image, 0, 0, null);
}
};
frame.add(pane);
}
private static JFrame buildFrame() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setSize(400, 400);
frame.setVisible(true);
return frame;
}
}
I reworked your Swing sandbox code a bit. Here's what I came up with.
The image is distorted because I made it fit a 400 x 400 drawing panel. You should reduce the image and maintain the aspect ratio.
Here are the changes I made.
I added the call to the SwingUtilities invokeLater method to put the Swing components on the Event Dispatch Thread.
I made the drawing panel a class, so I could set the preferred size. You set the size of the drawing panel, not the JFrame. Who cares how large or small the JFrame is?
I put the JFrame method calls in the correct order.
And here's the code.
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;
public class SwingSandbox implements Runnable {
public static void main(String[] args) throws IOException {
SwingUtilities.invokeLater(new SwingSandbox());
}
private BufferedImage image;
public SwingSandbox() {
try {
image = ImageIO.read(new File("C:\\Users\\Owner\\OneDrive\\Pictures\\Saved Pictures\\StockMarketGame.png"));
} catch (IOException e) {
e.printStackTrace();
}
}
#Override
public void run() {
JFrame frame = new JFrame("Image Display");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
DrawingPanel panel = new DrawingPanel(image);
frame.add(panel);
frame.pack();
frame.setVisible(true);
}
public class DrawingPanel extends JPanel {
private static final long serialVersionUID = 1L;
private BufferedImage image;
public DrawingPanel(BufferedImage image) {
this.image = image;
this.setPreferredSize(new Dimension(400, 400));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image, 0, 0, 400, 400, null);
}
}
}
You are changing how big is frame. You should use something like this: g.drawImage(image, 0, 0, 400, 400, null);
If this help you please vote me up. I’am here new and want to have some basic reputation. Thanks! 😀

Creating a class that extends Jlabel to draw a string to a panel. Nothing is currently being displayed

I am new to the swing and graphics and am trying to get this to work for drawing a string on a label by making an object class called DrawString. A panel currently pops up with nothing on it. I would like to thank you for any guidance you can give.
package view;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Run {
public static void main(String[] args) {
JPanel panel = new JPanel();
DrawString text = new DrawString();
JFrame window = new JFrame();
window.setVisible(true);
window.setSize(400, 400);
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
text.display("Boo");
panel.setLocation(((window.getWidth()/2)-(panel.getWidth()/2)),
((window.getHeight()/2)-(panel.getHeight()/2)));
panel.setSize(200, 200);
window.add(panel);
panel.add(text);
}
}
package view;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JLabel;
#SuppressWarnings("serial")
public class DrawString extends JLabel{
String string;
Font font = new Font("TimesRoman",Font.PLAIN, 30);
public DrawString() {
super();
}
public void display(String string){
this.string=string;
repaint();
}
public void drawString(Graphics comp){
super.paintComponent(comp);
Graphics2D g = (Graphics2D) comp;
g.setFont(font);
g.drawString(string, JLabel.CENTER, JLabel.CENTER);
}
}
I am learning and experimenting…
It's not clear if you want to experiment with JLabel or custom painting. You might want to start with a working JLabel#setText() example or TextLayout#draw() example.

Keyboard input with KeyAdapter

I'm trying to make a simple game in java where you can move the player (Defender) in the 4 directions. I tried to make the key detecting with a key adapter, but it doesn't work. What could be the problem (I tried to do a System.out.println at the key press to make sure that the problem isn't at the Defender)?
Code:
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class DefenderComponent extends JPanel implements ActionListener {
private static final long serialVersionUID = 1L;
private static final int WIDTH = 160;
private static final int HEIGHT = 120;
private static final int SCALE = 4;
Defender player = new Defender();
public DefenderComponent() {
Dimension size = new Dimension(WIDTH * SCALE, HEIGHT * SCALE);
setMinimumSize(size);
setMaximumSize(size);
setPreferredSize(size);
addKeyListener(new TKeyListener());
Timer timer = new Timer(5, this);
timer.start();
}
public static void main(String[] args) {
JFrame frame = new JFrame("Test2");
frame.add(new DefenderComponent());
frame.pack();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
frame.setFocusable(true);
new DefenderComponent();
}
public void paintComponent(Graphics g){
Graphics2D g2d = (Graphics2D) g;
Image i = player.getImage();
g2d.drawImage(i, player.getX(), player.getY(), i.getWidth(this) * SCALE, i.getHeight(this) * SCALE, this);
}
public void actionPerformed(ActionEvent e) {
player.move();
repaint();
}
}
KeyEvents are only generated for the component that has focus. A JPanel is not focusable by default.
Don't use a KeyListener. Instead you should be using Key Bindings which are more flexible.
See Motion Using the Keyboard for more information and examples.
frame.addActionListener(this);
is what you missed.
that line says. this class is an ActionListener. please call this class when you receive an action.
if you want to add the ActionListener to the JPanel
public DefenderComponent() {
addActionListener(this);
....
}

getWidth() returning 0 for panel

I want the racket to be positioned by using the getWidth method for the gamePanel, but it returns 0. It works fine for the frame, and it worked for the panel as well, but I decided to rewrite alot of the code and now I cant get it to work. Help is appreciated :)
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Oppgave1 extends JFrame {
public static void main(String[] args) {
JFrame frame = new Oppgave1();
frame.setTitle("Oppgave 1");
frame.setSize(600, 400);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
private JLabel jlbBallCount = new JLabel("Ballcount");
private JLabel jlbTimer = new JLabel("Timer");
private JButton jbtNewBall = new JButton("New Ball");
private Racket racket;
private Ball ball;
public Oppgave1() {
JPanel buttonPanel = new JPanel();
buttonPanel.add(jlbBallCount);
buttonPanel.add(jlbTimer);
buttonPanel.add(jbtNewBall);
JPanel gamePanel = new JPanel();
gamePanel.add(racket = new Racket (100, 60));
gamePanel.add(ball = new Ball(10, 3, racket));
this.add(gamePanel, BorderLayout.CENTER);
this.add(buttonPanel, BorderLayout.SOUTH);
}
public void paint(Graphics g){
racket.draw(g);
ball.draw(g);
}
}
Don't override the paint() method of a JFrame.
You added the racket and ball to the game panel. The game panel will now paint these components automatically.
If you want to be able to move these components then you must set the layout to null and initially set the bounds of the components. Then when you want to move the component you just invoke the setLocation() method and Swing will paint the component in its new position.

CardLayout in Java change by action in one of the 'cards'

I am making a simple game using a JFrame. I have made a simple "Start" screen which basically consists of a String and a JButton. I am picking up the button click with the actionPerformed(ActionEvent e) method. I don't know how to change the cards using a button click. This may seem like a simple problem to solve, but the twist comes with this: My main JFrame, my StartScreen and my JPanel where the game takes place are all in separate files. My main file, Virus.java, is where I create the JFrame. My file VirusGamePanel.java is where the game takes place. My file StartScreen.java is the screen with the button. I want to change 'cards' to the game screen when the player clicks the button. How can I do this?
My StartScreen.java file:
package virus;
import javax.swing.JPanel;
import java.awt.event.ActionListener;
import java.awt.Graphics;
import java.awt.Font;
import java.awt.Color;
import javax.swing.JButton;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.CardLayout;
public class StartScreen extends JPanel implements ActionListener{
private static final long serialVersionUID = 1L;
JButton start = new JButton("Start");
public StartScreen(){
start.addActionListener(this);
start.setBounds(new Rectangle(400,300,100,30));
this.add(start);
}
public void paint(Graphics g){
super.paint(g);
g.setFont(new Font("Impact",Font.BOLD,72));
g.setColor(Color.MAGENTA);
g.drawString("Virus",275,300);
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==start)
{
//what to do here?
}
}
}
My Virus.java file:
package virus;
import javax.swing.*;
import java.awt.CardLayout;
import virus.StartScreen;
public class Virus extends JFrame{
private static final long serialVersionUID =1L;
JFrame jf = new JFrame("Virus");
static JPanel thegame = new JPanel(new CardLayout());
JPanel game = new VirusGamePanel();
JPanel start = new StartScreen();
public Virus(){
jf.setResizable(false);
jf.setSize(600,600);
jf.setLocationRelativeTo(null);
jf.setDefaultCloseOperation(EXIT_ON_CLOSE);
jf.setVisible(true);
jf.add(thegame);
thegame.add(start);
thegame.add(game);
}
public static void main(String[] args) {
new Virus();
}
}
You simply have to right this in your actionPerformed(...) method :
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==start)
{
//what to do here?
CardLayout cardLayout = (CardLayout) Virus.thegame.getLayout();
cardLayout.next(Virus.thegame);
}
}
As very much pointed out by #kleopatra (THE EMPRESS) herself, don't override paint() instead do your painting stuff inside paintComponent(Graphics g) method of any JPanel/JComponent. Moreover, first add the components to your JFrame, once it's size is realized, then only set it to Visible, not before that. Instead of setting sizes for the JFrame simply override the JPanel's method getPreferredSize(), make it return some valid Dimension Object.
Do watch this sequence, as you write your code the next time :
public Virus(){
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jf.setResizable(false);
thegame.add(start);
thegame.add(game);
jf.add(thegame);
jf.pack();
jf.setLocationRelativeTo(null);
jf.setVisible(true);
}
Here is your full code :
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.event.ActionListener;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Font;
import java.awt.Color;
import javax.swing.JButton;
import javax.swing.JLabel;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.CardLayout;
public class Virus extends JFrame{
private static final long serialVersionUID =1L;
JFrame jf = new JFrame("Virus");
static JPanel thegame = new JPanel(new CardLayout());
JPanel game = new VirusGamePanel();
JPanel start = new StartScreen();
public Virus(){
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jf.setResizable(false);
thegame.add(start);
thegame.add(game);
jf.add(thegame);
jf.pack();
jf.setLocationRelativeTo(null);
jf.setVisible(true);
}
public static void main(String[] args) {
new Virus();
}
}
class StartScreen extends JPanel implements ActionListener{
private static final long serialVersionUID = 1L;
JButton start = new JButton("Start");
public StartScreen(){
start.addActionListener(this);
start.setBounds(new Rectangle(400,300,100,30));
this.add(start);
}
#Override
protected void paintComponent(Graphics g){
super.paintComponent(g);
g.setFont(new Font("Impact",Font.BOLD,72));
g.setColor(Color.MAGENTA);
g.drawString("Virus",275,300);
}
#Override
public Dimension getPreferredSize()
{
return (new Dimension(600, 600));
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==start)
{
//what to do here?
CardLayout cardLayout = (CardLayout) Virus.thegame.getLayout();
cardLayout.next(Virus.thegame);
}
}
}
class VirusGamePanel extends JPanel
{
public VirusGamePanel()
{
JLabel label = new JLabel("I am ON", JLabel.CENTER);
add(label);
}
#Override
public Dimension getPreferredSize()
{
return (new Dimension(600, 600));
}
}
Your StartScreen class has to have access to the instance of the CardLayout of the JFrame and the instance of the VirusGamePanel class. You can pass these instances in the constructor or a setLayout method and setVirusGamePanel method of your StartScreen class.
Something like:
layout.next(virusGamePanel);
should work.

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