So the answer to this might be completely obvious, but I just can't see it. Why is my Graphics object not displaying what I tell it to? I'm fairly certain I'm honoring Swing concurrency and such but perhaps not. Here's my JPanel code:
package com.kraken.towerdefense.graphics;
import com.kraken.towerdefense.TowerDefense;
import com.kraken.towerdefense.listener.KeyHandler;
import com.kraken.towerdefense.listener.MouseMotionHandler;
import com.kraken.towerdefense.scene.Scene;
import javax.swing.*;
import java.awt.*;
import java.awt.geom.RoundRectangle2D;
public class Screen extends JPanel implements Runnable {
Thread thread = new Thread(this);
private int FPS = 0;
public Scene scene;
TowerDefense tD;
private boolean running = false;
public RoundRectangle2D.Float playGame, quitGame;
public boolean playGameHighlighted, quitGameHighlighted;
#Override
public void run() {
long lastFrame = System.currentTimeMillis();
int frames = 0;
running = true;
while (running) {
repaint();
frames++;
if (System.currentTimeMillis() - 1000 >= lastFrame) {
FPS = frames;
frames = 0;
lastFrame = System.currentTimeMillis();
}
}
System.exit(0);
}
public Screen(TowerDefense tD) {
thread.start();
addKeyListener(new KeyHandler(this));
addMouseMotionListener(new MouseMotionHandler(this));
this.tD = tD;
scene = Scene.MENU;
}
#Override
public void paintComponent(Graphics g2) {
super.paintComponent(g2);
playGame = new RoundRectangle2D.Float((getWidth() / 2) - 200, (getHeight() / 2) - 100, 400, 100, 10, 10);
quitGame = new RoundRectangle2D.Float((getWidth() / 2) - 200, (getHeight() / 2) + 20, 400, 100, 10, 10);
Graphics2D g = (Graphics2D) g2.create();
g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g.clearRect(0, 0, getWidth(), getHeight());
g.drawString("FPS: " + FPS, 10, 10);
if (scene == Scene.MENU) {
if (playGameHighlighted) {
g.setColor(new Color(255, 152, 56));
} else {
g.setColor(new Color(4, 47, 61));
}
g.fill(playGame);
if (quitGameHighlighted) {
g.setColor(new Color(255, 152, 56));
} else {
g.setColor(new Color(4, 47, 61));
}
g.fill(quitGame);
g.setColor(Color.WHITE);
g.setFont(new Font("Gisha", Font.PLAIN, 20));
g.drawString("Play", (getWidth() / 2) - (g.getFontMetrics().stringWidth("Play") / 2), (getHeight() / 2) - 45);
g.drawString("Quit", (getWidth() / 2) - (g.getFontMetrics().stringWidth("Quit") / 2), (getHeight() / 2) + 75);
}
}
public class KeyTyped {
public void keyESC() {
running = false;
}
}
}
And here's my Scene Enum:
package com.kraken.towerdefense.scene;
public enum Scene {
MENU,
GAME
}
I'm pretty sure I don't need to supply the JFrame code, but if necessary I will. Any other solutions to problems in my code you could give would be greatly appreciated. Thanks!
EDIT 1
Here's my MouseMotionListener class:
package com.kraken.towerdefense.listener;
import com.kraken.towerdefense.graphics.Screen;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
public class MouseMotionHandler implements MouseMotionListener {
Screen screen;
public MouseMotionHandler(Screen screen) {
this.screen = screen;
}
#Override
public void mouseDragged(MouseEvent e) {
}
#Override
public void mouseMoved(MouseEvent e) {
if (screen.playGame.contains(e.getPoint())) {
screen.playGameHighlighted = true;
} else {
screen.playGameHighlighted = false;
}
if (screen.quitGame.contains(e.getPoint())) {
screen.quitGameHighlighted = true;
} else {
screen.playGameHighlighted = false;
}
}
}
Here's my JFrame code:
package com.kraken.towerdefense;
import com.kraken.towerdefense.graphics.Screen;
import javax.swing.*;
public class TowerDefense extends JFrame {
public static void main(String[] args) {
new TowerDefense();
}
public TowerDefense() {
setExtendedState(MAXIMIZED_BOTH);
setUndecorated(true);
setTitle("Tower Defense");
setDefaultCloseOperation(EXIT_ON_CLOSE);
setResizable(false);
Screen screen = new Screen(this);
this.add(screen);
setVisible(true);
}
}
And here's my KeyListener code:
package com.kraken.towerdefense.listener;
import com.kraken.towerdefense.graphics.Screen;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
public class KeyHandler implements KeyListener {
private Screen screen;
private Screen.KeyTyped keyTyped;
public KeyHandler(Screen screen) {
this.screen = screen;
keyTyped = screen.new KeyTyped();
}
#Override
public void keyTyped(KeyEvent e) {
}
#Override
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == 27) {
keyTyped.keyESC();
}
}
#Override
public void keyReleased(KeyEvent e) {
}
}
So those are all my classes, I hope that helps
So, I gutted your code to make it run and was capable of displaying...
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Graphics;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class GraphicsTest {
public static void main(String[] args) {
new GraphicsTest();
}
public GraphicsTest() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new Screen());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public enum Scene {
MENU,
GAME
}
public class Screen extends JPanel implements Runnable {
Thread thread = new Thread(this);
private int FPS = 0;
public Scene scene;
private boolean running = false;
#Override
public void run() {
long lastFrame = System.currentTimeMillis();
int frames = 0;
running = true;
scene = Scene.MENU;
while (running) {
repaint();
frames++;
if (System.currentTimeMillis() - 1000 >= lastFrame) {
FPS = frames;
frames = 0;
lastFrame = System.currentTimeMillis();
}
}
System.exit(0);
}
public Screen() {
thread.start();
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.clearRect(0, 0, getWidth(), getHeight());
g.drawString("FPS: " + FPS, 10, 10);
if (scene == Scene.MENU) {
g.setColor(Color.BLACK);
g.fillRoundRect((getWidth() / 2) - 100, (getHeight() / 2) - 50, 200, 100, 25, 25);
}
}
}
}
So that suggests that the problem you're describing is some where else.
To me this;
g.clearRect(0, 0, tD.getWidth(), tD.getHeight());
looks suspicious, as you're relying on the TowerDefense properties when you should relying on the components own width/height properties (apart from clearRect actually not been required in this context).
This further makes me suspicious that you're not actually adding the Screen component to anything that is displayable
The other possible problem is you're making use of an appropriate layout manager, but since your Screen class doesn't supply any preferredSize hints, this would be an additional issue which you're not demonstrating
Updated based on changes to the original question
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import static java.awt.Frame.MAXIMIZED_BOTH;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.RoundRectangle2D;
import javafx.scene.Scene;
import javax.swing.JFrame;
import static javax.swing.JFrame.EXIT_ON_CLOSE;
import javax.swing.JPanel;
public class TowerDefense extends JFrame {
public static void main(String[] args) {
new TowerDefense();
}
public TowerDefense() {
// setExtendedState(MAXIMIZED_BOTH);
// setUndecorated(true);
setTitle("Tower Defense");
setDefaultCloseOperation(EXIT_ON_CLOSE);
// setResizable(false);
Screen screen = new Screen(this);
this.add(screen);
pack();
setVisible(true);
}
public enum Scene {
MENU,
GAME
}
public class Screen extends JPanel implements Runnable {
Thread thread = new Thread(this);
private int FPS = 0;
public Scene scene;
TowerDefense tD;
private boolean running = false;
public RoundRectangle2D.Float playGame, quitGame;
public boolean playGameHighlighted, quitGameHighlighted;
#Override
public void run() {
// long lastFrame = System.currentTimeMillis();
// int frames = 0;
//
// running = true;
//
// while (running) {
// repaint();
//
// frames++;
//
// if (System.currentTimeMillis() - 1000 >= lastFrame) {
// FPS = frames;
// frames = 0;
//
// lastFrame = System.currentTimeMillis();
// }
// }
//
// System.exit(0);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 400);
}
public Screen(TowerDefense tD) {
thread.start();
addKeyListener(new KeyHandler(this));
addMouseMotionListener(
new MouseAdapter() {
#Override
public void mouseMoved(MouseEvent e) {
playGameHighlighted = playGame.contains(e.getPoint());
quitGameHighlighted = quitGame.contains(e.getPoint());
repaint();
}
});
this.tD = tD;
scene = Scene.MENU;
}
#Override
public void paintComponent(Graphics g2) {
super.paintComponent(g2);
playGame = new RoundRectangle2D.Float((getWidth() / 2) - 200, (getHeight() / 2) - 100, 400, 100, 10, 10);
quitGame = new RoundRectangle2D.Float((getWidth() / 2) - 200, (getHeight() / 2) + 20, 400, 100, 10, 10);
Graphics2D g = (Graphics2D) g2.create();
g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g.clearRect(0, 0, getWidth(), getHeight());
g.drawString("FPS: " + FPS, 10, 10);
if (scene == Scene.MENU) {
if (playGameHighlighted) {
g.setColor(new Color(255, 152, 56));
} else {
g.setColor(new Color(4, 47, 61));
}
g.draw(playGame);
if (quitGameHighlighted) {
g.setColor(new Color(255, 152, 56));
} else {
g.setColor(new Color(4, 47, 61));
}
g.draw(quitGame);
g.setColor(Color.WHITE);
g.setFont(new Font("Gisha", Font.PLAIN, 20));
g.drawString("Play", (getWidth() / 2) - (g.getFontMetrics().stringWidth("Play") / 2), (getHeight() / 2) - 45);
g.drawString("Quit", (getWidth() / 2) - (g.getFontMetrics().stringWidth("Quit") / 2), (getHeight() / 2) + 75);
}
}
public class KeyTyped {
public void keyESC() {
running = false;
}
}
}
public class KeyHandler implements KeyListener {
private Screen screen;
private Screen.KeyTyped keyTyped;
public KeyHandler(Screen screen) {
this.screen = screen;
keyTyped = screen.new KeyTyped();
}
#Override
public void keyTyped(KeyEvent e) {
}
#Override
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == 27) {
keyTyped.keyESC();
}
}
#Override
public void keyReleased(KeyEvent e) {
}
}
}
Related
I have 2 classes: TestingPanel and SnipIt.
SnipIt is used for selecting an area on the screen.
TestingPanel is the main frame, containing a button to run method Snip() and receiving the return values.
If I test the SnipIt class separately, it works. But if I create a SnipIt object and run method Snip() from TestingPanel class, it doesn't work. The GUI just freezes and doesn't respond to mouse click or drag event. I guess something block the thread handle the mouse events but I'm not sure.
I have been stuck for couple hours and still don't know what caused the issue. Please help.
TestingPanel
package Testing;
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JButton;
import java.awt.BorderLayout;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class TestingPanel {
private JFrame frame;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
TestingPanel window = new TestingPanel();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
public TestingPanel() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
private void initialize() {
frame = new JFrame();
frame.setBounds(100, 100, 200, 160);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(null);
JButton btnSnip = new JButton("Snip");
btnSnip.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
getSelectionSize();
}
});
btnSnip.setBounds(47, 87, 89, 23);
frame.getContentPane().add(btnSnip);
}
private void getSelectionSize() {
int[] size = new int[4];
Thread worker = new Thread(new Runnable() {
public void run() {
SnipIt sn = new SnipIt();
sn.snip();
while(!sn.complete) {
try {
Thread.sleep(800);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
size[0] = sn.returnSize()[0];
size[1] = sn.returnSize()[1];
size[2] = sn.returnSize()[2];
size[3] = sn.returnSize()[3];
}
});
worker.start();
try {
worker.join();
} catch (InterruptedException e1) {
e1.printStackTrace();
}
System.out.println(size[0] + " " + size[1] + " " + size[2] + " " + size[3]);
}
}
SnipIt
package Testing;
import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Area;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
public class SnipIt {
private int recX = 0;
private int recY = 0;
private int recWidth = 0;
private int recHeight = 0;
public boolean complete = false;
/*
public static void main(String [] args)
{
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
SnipIt s = new SnipIt();
s.snip();
}
});
}
*/
public void snip() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception ex) {
}
JFrame frame = new JFrame();
frame.setUndecorated(true);
frame.setBackground(new Color(0, 0, 0, 0));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new SnipItPane());
frame.setBounds(getVirtualBounds());
frame.setVisible(true);
}
#SuppressWarnings("serial")
public class SnipItPane extends JPanel {
private Point mouseAnchor;
private Point dragPoint;
private SelectionPane selectionPane;
private ControlPane controlPane;
public SnipItPane() {
setOpaque(false);
setLayout(null);
selectionPane = new SelectionPane();
controlPane = new ControlPane();
add(selectionPane);
add(controlPane);
MouseAdapter adapter = new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
mouseAnchor = e.getPoint();
dragPoint = null;
selectionPane.setLocation(mouseAnchor);
selectionPane.setSize(0, 0);
controlPane.setLocation(mouseAnchor);
controlPane.setSize(0, 0);
}
#Override
public void mouseDragged(MouseEvent e) {
dragPoint = e.getPoint();
int width = dragPoint.x - mouseAnchor.x;
int height = dragPoint.y - mouseAnchor.y;
int x = mouseAnchor.x;
int y = mouseAnchor.y;
if (width < 0) {
x = dragPoint.x;
width *= -1;
}
if (height < 0) {
y = dragPoint.y;
height *= -1;
}
selectionPane.setBounds(x, y, width, height);
selectionPane.revalidate();
int controlY = y + height + 5;
controlPane.setBounds(x, controlY, width, 25);
controlPane.revalidate();
repaint();
}
};
addMouseListener(adapter);
addMouseMotionListener(adapter);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
Rectangle bounds = new Rectangle(0, 0, getWidth(), getHeight());
Area area = new Area(bounds);
area.subtract(new Area(selectionPane.getBounds()));
g2d.setColor(new Color(102, 102, 102, 80));
g2d.fill(area);
}
}
#SuppressWarnings("serial")
public class ControlPane extends JPanel {
private JButton btnClose;
public ControlPane() {
setOpaque(false);
btnClose = new JButton("Save");
setLayout(new BorderLayout());
this.add(btnClose, BorderLayout.NORTH);
btnClose.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
complete = true;
SwingUtilities.getWindowAncestor(ControlPane.this).dispose();
}
});
}
}
#SuppressWarnings("serial")
public class SelectionPane extends JPanel {
public SelectionPane() {
setOpaque(false);
addComponentListener(new ComponentAdapter() {
#Override
public void componentResized(ComponentEvent e) {
recX = getX();
recY = getY();
recWidth = getWidth();
recHeight = getHeight();
}
});
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
float strokeWidth = 1.0f;
float dash1[] = {10.0f};
BasicStroke dashed =
new BasicStroke(strokeWidth,
BasicStroke.CAP_BUTT,
BasicStroke.JOIN_MITER,
10.0f, dash1, 0.0f);
g2d.setColor(Color.BLACK);
g2d.setStroke(dashed);
g2d.drawRect(0, 0, getWidth() - 1, getHeight() - 1);
g2d.dispose();
}
}
public static Rectangle getVirtualBounds() {
Rectangle bounds = new Rectangle(0, 0, 0, 0);
GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
GraphicsDevice lstGDs[] = ge.getScreenDevices();
for (GraphicsDevice gd : lstGDs) {
bounds.add(gd.getDefaultConfiguration().getBounds());
}
return bounds;
}
public int[] returnSize() {
int[] size = new int[4];
size[0] = recX;
size[1] = recY;
size[2] = recWidth;
size[3] = recHeight;
return size;
}
}
You're running the Snipit application in a background thread and then freezing that thread with Thread.sleep and a while true block, something guaranteed to freeze the GUI. Read Lesson: Concurrency in Swing and then be sure to always run Swing applications on the single Swing event thread, and do any long running or sleeping code in a background thread.
Possible solutions to your issue:
Make the Snipit window an undecorated modal dialog. This way program flow from the calling code stops when the dialog is visible and resumes when no longer visible.
Or Make the Snipit window JFrame an instance field of the class and allow outside classes to add listeners to it so that they will be notified when it closes.
e.g.,
import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dialog.ModalityType;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Area;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
public class TestSnipit {
private static void createAndShowGui() {
boolean runTest = true;
if (runTest) {
TestingPanel.main(null);
} else {
SnipIt.main(null);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}
class TestingPanel {
private JFrame frame;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
TestingPanel window = new TestingPanel();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
public TestingPanel() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
private void initialize() {
frame = new JFrame();
frame.setBounds(100, 100, 200, 160);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(null);
JButton btnSnip = new JButton("Snip");
btnSnip.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
getSelectionSize();
}
});
btnSnip.setBounds(47, 87, 89, 23);
frame.getContentPane().add(btnSnip);
}
private void getSelectionSize() {
int[] size = new int[4];
// !!
SnipIt sn = new SnipIt();
sn.snip(frame);
// Thread worker = new Thread(new Runnable() {
// public void run() {
// SnipIt sn = new SnipIt();
// sn.snip();
//
// while (!sn.complete) {
// try {
// Thread.sleep(800);
// } catch (InterruptedException e) {
// e.printStackTrace();
// }
// }
//
size[0] = sn.returnSize()[0];
size[1] = sn.returnSize()[1];
size[2] = sn.returnSize()[2];
size[3] = sn.returnSize()[3];
// }
// });
//
// worker.start();
//
// try {
// worker.join();
// } catch (InterruptedException e1) {
// e1.printStackTrace();
// }
System.out.println(size[0] + " " + size[1] + " " + size[2] + " " + size[3]);
}
}
class SnipIt {
private int recX = 0;
private int recY = 0;
private int recWidth = 0;
private int recHeight = 0;
public boolean complete = false;
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
SnipIt s = new SnipIt();
s.snip(null); // !!
}
});
}
public void snip(Window owner) { // !!
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception ex) {
}
// JFrame frame = new JFrame();
JDialog frame = new JDialog(owner, null, ModalityType.APPLICATION_MODAL); // !!
frame.setUndecorated(true);
frame.setBackground(new Color(0, 0, 0, 0));
// frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE); // !!
frame.setLayout(new BorderLayout());
frame.add(new SnipItPane());
frame.setBounds(getVirtualBounds());
frame.setVisible(true);
}
#SuppressWarnings("serial")
public class SnipItPane extends JPanel {
private Point mouseAnchor;
private Point dragPoint;
private SelectionPane selectionPane;
private ControlPane controlPane;
public SnipItPane() {
setOpaque(false);
setLayout(null);
selectionPane = new SelectionPane();
controlPane = new ControlPane();
add(selectionPane);
add(controlPane);
MouseAdapter adapter = new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
mouseAnchor = e.getPoint();
dragPoint = null;
selectionPane.setLocation(mouseAnchor);
selectionPane.setSize(0, 0);
controlPane.setLocation(mouseAnchor);
controlPane.setSize(0, 0);
}
#Override
public void mouseDragged(MouseEvent e) {
dragPoint = e.getPoint();
int width = dragPoint.x - mouseAnchor.x;
int height = dragPoint.y - mouseAnchor.y;
int x = mouseAnchor.x;
int y = mouseAnchor.y;
if (width < 0) {
x = dragPoint.x;
width *= -1;
}
if (height < 0) {
y = dragPoint.y;
height *= -1;
}
selectionPane.setBounds(x, y, width, height);
selectionPane.revalidate();
int controlY = y + height + 5;
controlPane.setBounds(x, controlY, width, 25);
controlPane.revalidate();
repaint();
}
};
addMouseListener(adapter);
addMouseMotionListener(adapter);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
Rectangle bounds = new Rectangle(0, 0, getWidth(), getHeight());
Area area = new Area(bounds);
area.subtract(new Area(selectionPane.getBounds()));
g2d.setColor(new Color(102, 102, 102, 80));
g2d.fill(area);
}
}
#SuppressWarnings("serial")
public class ControlPane extends JPanel {
private JButton btnClose;
public ControlPane() {
setOpaque(false);
btnClose = new JButton("Save");
setLayout(new BorderLayout());
this.add(btnClose, BorderLayout.NORTH);
btnClose.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
complete = true;
SwingUtilities.getWindowAncestor(ControlPane.this).dispose();
}
});
}
}
#SuppressWarnings("serial")
public class SelectionPane extends JPanel {
public SelectionPane() {
setOpaque(false);
addComponentListener(new ComponentAdapter() {
#Override
public void componentResized(ComponentEvent e) {
recX = getX();
recY = getY();
recWidth = getWidth();
recHeight = getHeight();
}
});
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
float strokeWidth = 1.0f;
float dash1[] = { 10.0f };
BasicStroke dashed = new BasicStroke(strokeWidth, BasicStroke.CAP_BUTT,
BasicStroke.JOIN_MITER, 10.0f, dash1, 0.0f);
g2d.setColor(Color.BLACK);
g2d.setStroke(dashed);
g2d.drawRect(0, 0, getWidth() - 1, getHeight() - 1);
g2d.dispose();
}
}
public static Rectangle getVirtualBounds() {
Rectangle bounds = new Rectangle(0, 0, 0, 0);
GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
GraphicsDevice lstGDs[] = ge.getScreenDevices();
for (GraphicsDevice gd : lstGDs) {
bounds.add(gd.getDefaultConfiguration().getBounds());
}
return bounds;
}
public int[] returnSize() {
int[] size = new int[4];
size[0] = recX;
size[1] = recY;
size[2] = recWidth;
size[3] = recHeight;
return size;
}
}
A side issue unrelated to your initial problem is your use of null layougs. While null layouts and setBounds() might seem to Swing newbies like the easiest and best way to create complex GUI's, the more Swing GUI'S you create the more serious difficulties you will run into when using them. They won't resize your components when the GUI resizes, they are a royal witch to enhance or maintain, they fail completely when placed in scrollpanes, they look gawd-awful when viewed on all platforms or screen resolutions that are different from the original one.
I want to create a continuous animation of a moving truck in java applets. In this the truck should reappear from the other side as soon as it disappears.
I tried using one truck but then it appears on the other side only after completely disappearing from one side. Hence, I used two.
Following is my code:
public class prc1 extends Applet implements Runnable{
Thread t;
int x=0;
int y=0;
int i;
public void start(){
t = new Thread(this);
t.start();
}
public void paint(Graphics g){
g.setColor(Color.gray);
g.fillRect(x,10,70,45);
g.setColor(Color.yellow);
g.fillRoundRect(50+x,15,35,35,10,10);
g.setColor(Color.black);
g.fillArc(5+x,50,10,10,0,360);
g.fillArc(55+x,50,10,10,0,360);
g.setColor(Color.gray);
g.fillRect(y,10,70,45);
g.setColor(Color.yellow);
g.fillRoundRect(50+y,15,35,35,10,10);
g.setColor(Color.black);
g.fillArc(5+y,50,10,10,0,360);
g.fillArc(55+y,50,10,10,0,360);
}
public void run(){
try{
y=-90;
x=0;
for(; ;){
Thread.sleep(100);
repaint();
run();
x=x+5;
if(x==400){
for(; ;){
y=y+5;
Thread.sleep(100);
repaint();
run();
x=x-5;
if(x==0){
y=-90;
break;
}
}
}
}
}catch(InterruptedException e){ }
}
}
Now the problem is that the truck does not move at all.
So the basic idea is, you need to determine when the truck begins to leave the viewable area and then calculate the amount of "overflow", which would then allow you to paint the truck a second time at a new position subtracted from the overflow.
I've broken you code down so the Truck is it's own class, this makes it easier to deal with and allows a little more control over the painting process.
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private Truck truck;
public TestPane() {
truck = new Truck();
Timer timer = new Timer(40, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
truck.update(getSize());
repaint();
}
});
timer.start();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
truck.paint(g2d);
g2d.dispose();
}
}
public class Truck {
private int x, y;
// I had to calculate these
private int width = 85;
private int height = 65;
private int xDelta = 4;
private int xOverFlow = 0;
public void update(Dimension bounds) {
x += xDelta;
if (x > bounds.width) {
x = 0;
}
if (x + width > bounds.width) {
xOverFlow = (x + width) - bounds.width;
} else {
xOverFlow = -1;
}
}
public void paint(Graphics2D g) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.translate(x, y);
paintTruck(g2d);
g2d.dispose();
if (xOverFlow > 0) {
g2d = (Graphics2D) g.create();
g2d.translate(xOverFlow - width, y);
paintTruck(g2d);
g2d.dispose();
}
}
protected void paintTruck(Graphics2D g2d) {
g2d.setColor(Color.gray);
g2d.fillRect(0, 10, 70, 45);
g2d.setColor(Color.yellow);
g2d.fillRoundRect(50, 15, 35, 35, 10, 10);
g2d.setColor(Color.black);
g2d.fillArc(5, 50, 10, 10, 0, 360);
g2d.fillArc(55, 50, 10, 10, 0, 360);
g2d.setColor(Color.gray);
g2d.fillRect(0, 10, 70, 45);
g2d.setColor(Color.yellow);
g2d.fillRoundRect(50, 15, 35, 35, 10, 10);
g2d.setColor(Color.black);
g2d.fillArc(5, 50, 10, 10, 0, 360);
g2d.fillArc(55, 50, 10, 10, 0, 360);
}
}
}
Another option might be to have more than one instance of truck, so as the second one begins to leave the viewable you could create another one
For example...
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private List<Truck> trucks;
public TestPane() {
trucks = new ArrayList<>(2);
trucks.add(new Truck());
Timer timer = new Timer(40, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
Truck[] truckArray = trucks.toArray(new Truck[trucks.size()]);
for (Truck truck : truckArray) {
truck.update(getSize());
if (truck.getX() > getWidth()) {
trucks.remove(truck);
} else if (truck.getX() + truck.getWidth() > getWidth() && trucks.size() == 1) {
trucks.add(new Truck());
}
}
repaint();
}
});
timer.start();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
for (Truck truck : trucks) {
truck.paint(g2d);
}
g2d.dispose();
}
}
public class Truck {
// I had to calculate these
private int width = 85;
private int height = 65;
private int x = -width;
private int y;
private int xDelta = 4;
public void update(Dimension bounds) {
x += xDelta;
}
public int getX() {
return x;
}
public int getY() {
return y;
}
public int getWidth() {
return width;
}
public int getHeight() {
return height;
}
public void paint(Graphics2D g) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.translate(x, y);
paintTruck(g2d);
g2d.dispose();
}
protected void paintTruck(Graphics2D g2d) {
g2d.setColor(Color.gray);
g2d.fillRect(0, 10, 70, 45);
g2d.setColor(Color.yellow);
g2d.fillRoundRect(50, 15, 35, 35, 10, 10);
g2d.setColor(Color.black);
g2d.fillArc(5, 50, 10, 10, 0, 360);
g2d.fillArc(55, 50, 10, 10, 0, 360);
g2d.setColor(Color.gray);
g2d.fillRect(0, 10, 70, 45);
g2d.setColor(Color.yellow);
g2d.fillRoundRect(50, 15, 35, 35, 10, 10);
g2d.setColor(Color.black);
g2d.fillArc(5, 50, 10, 10, 0, 360);
g2d.fillArc(55, 50, 10, 10, 0, 360);
}
}
}
I have created a program that just moves a ball across a screen. I used to have it all in one class, but decided that it looked too messy so I split it up into three different classes: Main... initializes everything, Game... which paints everything and is a JPanel, and AL which is a KeyListener (which is also where the problem is). The problem is that I can't get the program to repaint from my AL class no matter what I try to pass into it. Can anyone help with this? Here are my three classes:
import java.awt.Color;
import javax.swing.JFrame;
public class Main {
static Game game;
static JFrame frame;
public static void main(String[] args) {
game = new Game();
frame = new JFrame();
frame.getContentPane().add(game);
frame.addKeyListener(new AL(game, frame));
frame.setTitle("Game");
frame.setSize(500, 500);
frame.setResizable(true);
frame.setVisible(true);
frame.setBackground(Color.BLACK);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
-
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Game extends JPanel implements Runnable {
int x, y, xCoord, yCoord;
private Image dbImage;
private Graphics dbg;
JFrame frame;
public void changeCoord() {
x += xCoord;
y += yCoord;
if (x <= 20) {
x = 20;
}
if (x >= 480) {
x = 480;
}
if (y <= 40) {
y = 40;
}
if (y >= 480) {
y = 480;
}
}
public void setXCoord(int xcoord) {
xCoord = xcoord;
}
public void setYCoord(int ycoord) {
yCoord = ycoord;
}
public static void main(String[] args) {
Game game = new Game();
Thread t = new Thread(game);
t.start();
}
public Game() {
x = 250;
y = 250;
}
#Override
public void paintComponent(Graphics g) {
g.setColor(Color.GREEN);
g.fillOval(x, y, 15, 15);
}
#Override
public void paint(Graphics g) {
dbImage = createImage(getWidth(), getHeight());
dbg = dbImage.getGraphics();
paintComponent(dbg);
g.drawImage(dbImage, 0, 0, this);
}
#Override
public void run() {
try {
while (true) {
changeCoord();
Thread.sleep(30);
}
} catch (Exception e) {
System.out.println(e.getMessage());
}
}
}
-
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import javax.swing.JFrame;
public class AL extends KeyAdapter {
Game game;
JFrame frame;
public AL(Game game, JFrame frame) {
this.game = game;
this.frame = frame;
}
#Override
public void keyPressed(KeyEvent e) {
int keyCode = e.getKeyCode();
if (keyCode == e.VK_LEFT) {
game.setXCoord(-1);
}
if (keyCode == e.VK_RIGHT) {
game.setXCoord(+1);
}
if (keyCode == e.VK_UP) {
game.setYCoord(-1);
}
if (keyCode == e.VK_DOWN) {
game.setYCoord(+1);
}
game.repaint();
}
#Override
public void keyReleased(KeyEvent e) {
int keyCode = e.getKeyCode();
if (keyCode == e.VK_LEFT) {
game.setXCoord(0);
}
if (keyCode == e.VK_RIGHT) {
game.setXCoord(0);
}
if (keyCode == e.VK_UP) {
game.setYCoord(0);
}
if (keyCode == e.VK_DOWN) {
game.setYCoord(0);
}
game.repaint();
}
}
Let's start with the obvious....
This is problematic...
#Override
public void paintComponent(Graphics g) {
g.setColor(Color.GREEN);
g.fillOval(x, y, 15, 15);
}
#Override
public void paint(Graphics g) {
dbImage = createImage(getWidth(), getHeight());
dbg = dbImage.getGraphics();
paintComponent(dbg);
g.drawImage(dbImage, 0, 0, this);
}
There's no need to implement double buffering in Swing components, they already are. Also, you're breaking the painting contract, by not call the paint methods super methods
The whole thing should be...
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.GREEN);
g.fillOval(x, y, 15, 15);
}
See Painting in AWT and Swing and Performing Custom Painting for more details
KeyListener is well known for been problematic. It will only raise key events if the component it registered to is focuable AND has keyboard focus. A JPanel by default, is not focusable. Before you run of and try and make it focusable (and get bitterly disappointed), you should be using the Key Bindings API instead, which was designed to over come the limitations of KeyListener
As a basic example...
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.ActionMap;
import javax.swing.InputMap;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.KeyStroke;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new Game());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class Game extends JPanel {
int x, y, xCoord, yCoord;
public Game() {
x = 250;
y = 250;
addKeyBinding(KeyEvent.VK_LEFT, "move.left", new MoveAction(this, -1, 0));
addKeyBinding(KeyEvent.VK_RIGHT, "move.right", new MoveAction(this, 1, 0));
addKeyBinding(KeyEvent.VK_UP, "move.up", new MoveAction(this, 0, -1));
addKeyBinding(KeyEvent.VK_DOWN, "move.down", new MoveAction(this, 0, 1));
}
protected void addKeyBinding(int keyCode, String name, Action action) {
addKeyBinding(KeyStroke.getKeyStroke(keyCode, 0), name, action);
}
protected void addKeyBinding(KeyStroke keyStroke, String name, Action action) {
InputMap inputMap = getInputMap(WHEN_IN_FOCUSED_WINDOW);
ActionMap actionMap = getActionMap();
inputMap.put(keyStroke, name);
actionMap.put(name, action);
}
public void changeCoord() {
x += xCoord;
y += yCoord;
if (x <= 20) {
x = 20;
}
if (x >= 480) {
x = 480;
}
if (y <= 40) {
y = 40;
}
if (y >= 480) {
y = 480;
}
repaint();
}
public void setXCoord(int xcoord) {
xCoord = xcoord;
changeCoord();
}
public void setYCoord(int ycoord) {
yCoord = ycoord;
changeCoord();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(480, 480);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.GREEN);
g.fillOval(x, y, 15, 15);
}
}
public class MoveAction extends AbstractAction {
private int xDelta;
private int yDelta;
// I'd prefer an interface with just the "move" methods, but
// that's more time I don't have
private Game game;
public MoveAction(Game game, int xDelta, int yDelta) {
this.xDelta = xDelta;
this.yDelta = yDelta;
this.game = game;
}
#Override
public void actionPerformed(ActionEvent e) {
game.setXCoord(xDelta);
game.setYCoord(yDelta);
}
}
}
But, wait, that isn't exactly what you want (trust me, I'm an anoymouse person on the Internet ;)), a better example might be...
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.util.HashSet;
import java.util.Set;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.ActionMap;
import javax.swing.InputMap;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.KeyStroke;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new Game());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public enum Direction {
UP,
LEFT,
DOWN,
RIGHT;
}
public class Game extends JPanel {
int x, y, xCoord, yCoord;
private Set<Direction> movement;
public Game() {
x = 250;
y = 250;
movement = new HashSet<>(4);
addKeyPressedBinding(KeyEvent.VK_LEFT, "left.pressed", new MoveAction(movement, Direction.LEFT, true));
addKeyReleasedBinding(KeyEvent.VK_LEFT, "left.released", new MoveAction(movement, Direction.LEFT, false));
addKeyPressedBinding(KeyEvent.VK_RIGHT, "right.pressed", new MoveAction(movement, Direction.RIGHT, true));
addKeyReleasedBinding(KeyEvent.VK_RIGHT, "right.released", new MoveAction(movement, Direction.RIGHT, false));
addKeyPressedBinding(KeyEvent.VK_UP, "up.pressed", new MoveAction(movement, Direction.UP, true));
addKeyReleasedBinding(KeyEvent.VK_UP, "up.released", new MoveAction(movement, Direction.UP, false));
addKeyPressedBinding(KeyEvent.VK_DOWN, "down.pressed", new MoveAction(movement, Direction.DOWN, true));
addKeyReleasedBinding(KeyEvent.VK_DOWN, "down.released", new MoveAction(movement, Direction.DOWN, false));
Timer timer = new Timer(40, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
changeCoord();
}
});
timer.start();
}
protected void addKeyBinding(int keyCode, String name, Action action) {
addKeyBinding(KeyStroke.getKeyStroke(keyCode, 0), name, action);
}
protected void addKeyPressedBinding(int keyCode, String name, Action action) {
addKeyBinding(KeyStroke.getKeyStroke(keyCode, 0, false), name, action);
}
protected void addKeyReleasedBinding(int keyCode, String name, Action action) {
addKeyBinding(KeyStroke.getKeyStroke(keyCode, 0, true), name, action);
}
protected void addKeyBinding(KeyStroke keyStroke, String name, Action action) {
InputMap inputMap = getInputMap(WHEN_IN_FOCUSED_WINDOW);
ActionMap actionMap = getActionMap();
inputMap.put(keyStroke, name);
actionMap.put(name, action);
}
public void changeCoord() {
if (movement.contains(Direction.UP)) {
y--;
} else if (movement.contains(Direction.DOWN)) {
y++;
}
if (movement.contains(Direction.LEFT)) {
x--;
} else if (movement.contains(Direction.RIGHT)) {
x++;
}
x += xCoord;
y += yCoord;
if (x <= 20) {
x = 20;
}
if (x >= 480) {
x = 480;
}
if (y <= 40) {
y = 40;
}
if (y >= 480) {
y = 480;
}
repaint();
}
public void setXCoord(int xcoord) {
xCoord = xcoord;
changeCoord();
}
public void setYCoord(int ycoord) {
yCoord = ycoord;
changeCoord();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(480, 480);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.GREEN);
g.fillOval(x, y, 15, 15);
}
}
public class MoveAction extends AbstractAction {
private Set<Direction> movement;
private Direction direction;
private boolean pressed;
public MoveAction(Set<Direction> movement, Direction direction, boolean pressed) {
this.movement = movement;
this.direction = direction;
this.pressed = pressed;
}
#Override
public void actionPerformed(ActionEvent e) {
if (pressed) {
movement.add(direction);
} else {
movement.remove(direction);
}
}
}
}
What this does is simply activates a flag when a key is pressed (and deactivates it when it's released), then in a Swing Timer, we check which keys are "active" and update the location of the ball.
What this does is, eliminates the key "stutter" which is caused by the OS when a key is first pressed and held. A delay is inserted between the first key and the repeated key events. Instead, we just turn the flag on and off as we like.
It also allows you to move in two directions at the same time (horizontally and vertically)
Have a look at Concurrency in Swing and How to use Swing Timers for more details
I have a program which is simple in function. On start, it creates a random circle which it places in the window/frame. When that circle is clicked, it should dissappear, and spawn a new circle elsewhere. the issue is, my program does this, but you see all the past circles unless you minimize/reopen the window. I cannot get it to repaint without my help... and I do NOT know why. Here is my code.
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.geom.Ellipse2D;
import java.util.ArrayList;
import java.util.Random;
import javax.swing.JFrame;
public class Core extends JFrame implements MouseListener{
public static ArrayList<Ellipse2D> list = new ArrayList<Ellipse2D>();
Random r = new Random();
public Ellipse2D spawn(){
int x = r.nextInt(this.getWidth());
int y = r.nextInt(this.getHeight());
while(x<75||x>this.getWidth()-150){
x = r.nextInt(this.getWidth());
}
while(y<75||y>this.getHeight()-150){
y = r.nextInt(this.getHeight());
}
System.out.println("MAKING SHAPE at :" + x + " AND " + y);
return new Ellipse2D.Double(x, y, 75, 75);
}
public void mouseClicked(MouseEvent me) {
// Save the coordinates of the click lke this.
if(list.get(0).contains(me.getPoint())){
System.out.println("CLICKED SHAPE!");
list.clear();
list.add(spawn());
}
revalidate();
repaint();
}
public void mouseEntered(MouseEvent e) {
}
public void mouseReleased(MouseEvent e) {
}
public void mousePressed(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
}
#Override
public void paint(Graphics g) {
if(list.size()==0){
System.out.println("oops");
}
if(!list.isEmpty()){
System.out.println("DRAW");
int x =(int) list.get(0).getX();
int y =(int) list.get(0).getY();
int width = (int) list.get(0).getWidth();
int height = (int) list.get(0).getHeight();
g.setColor(Color.red);
g.drawOval(x,y, width, height);
}
}
public Core(){
setSize(500, 500);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.addMouseListener(this);
list.add(spawn());
setVisible(true);
}
public static void main(String args[]) {
EventQueue.invokeLater(new Runnable() {
public void run() {
new Core();
}
});
}
}
Your code works perfectly fine for me, however...
Don't override paint of top level containers like JFrame, JFrame contains a JRootPane, which contains a contentPane and may also have a visible glassPane, all of which can overpaint what is painted within the paint method. As a general rule, you shouldn't extend from JFrame (or other top level containers), you are locking yourself into a single use case, reducing the re-usability of your component and you're not actually any new functionality to the class. Instead, use a JPanel and override it's paintComponent method
Call super.paint before doing any custom painting. If, however, you use a JPanel, call super.paintComponent. Painting is performed by a series of methods which are chained together to generate the final output. See Painting in AWT and Swing and Performing Custom Painting for more details
Consider using something like x = r.nextInt(this.getWidth() - 150) + 75; and y = r.nextInt(this.getWidth() - 150) + 75; instead of your while loops, I think you might find them safer to use
For example...
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Ellipse2D;
import java.util.ArrayList;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Core {
public static void main(String args[]) {
EventQueue.invokeLater(new Runnable() {
public void run() {
new Core();
}
});
}
public Core() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new CorePane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class CorePane extends JPanel {
private ArrayList<Ellipse2D> list = new ArrayList<Ellipse2D>();
private Random r = new Random();
public Ellipse2D spawn() {
int x = r.nextInt(this.getWidth());
int y = r.nextInt(this.getHeight());
x = r.nextInt(this.getWidth() - 150) + 75;
y = r.nextInt(this.getWidth() - 150) + 75;
System.out.println("MAKING SHAPE at :" + x + " AND " + y);
return new Ellipse2D.Double(x, y, 75, 75);
}
public CorePane() {
addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent me) {
// Save the coordinates of the click lke this.
if (list.get(0).contains(me.getPoint())) {
list.clear();
list.add(spawn());
}
revalidate();
repaint();
}
});
}
#Override
public void invalidate() {
super.invalidate();
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
if (list.isEmpty()) {
list.add(spawn());
}
}
});
}
#Override
public Dimension getPreferredSize() {
return new Dimension(500, 500);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
if (!list.isEmpty()) {
for (Ellipse2D ellipse : list) {
g2d.setColor(Color.red);
g2d.draw(ellipse);
}
}
g2d.dispose();
}
}
}
Or, based on what I believe you're trying to do, you could simply do something like...
public class CorePane extends JPanel {
private Random r = new Random();
private Ellipse2D ellipse;
public Ellipse2D spawn() {
int x = r.nextInt(this.getWidth());
int y = r.nextInt(this.getHeight());
x = r.nextInt(this.getWidth() - 150) + 75;
y = r.nextInt(this.getWidth() - 150) + 75;
System.out.println("MAKING SHAPE at :" + x + " AND " + y);
return new Ellipse2D.Double(x, y, 75, 75);
}
public CorePane() {
addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent me) {
if (ellipse != null && ellipse.contains(me.getPoint())) {
ellipse = spawn();
}
revalidate();
repaint();
}
});
}
#Override
public void invalidate() {
super.invalidate();
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
spawn();
}
});
}
#Override
public Dimension getPreferredSize() {
return new Dimension(500, 500);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
if (ellipse != null) {
g2d.setColor(Color.red);
g2d.draw(ellipse);
}
g2d.dispose();
}
}
I've been trying to work this code, it's like when you hover over the start button it should change its color to gray, but whenever i hover over it. nothing happens, can somebody tell me why? i didn't get any error and it seems like my mousemoved listener isn't recognized by the compiler, sorry for my english. I haven't finish it yet but here is the code:
class Contents extends JFrame implements Runnable {
private Image dbi;
private Graphics dbg;
private boolean isStarted, isHovered;
private int x,y,xDir,yDir,bx,by,timer,life,my,mx,mhx,mhy;
private Rectangle startgame = new Rectangle(80,100,150,40);
Contents()
{
super();
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
if(isStarted)
setSize(600,600);
else
{
setSize(300,300);
setBackground(Color.BLUE);
}
setLocationRelativeTo(null);
isStarted = false;
isHovered = false;
addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
mx = e.getX();
my = e.getY();
if(mx > startgame.x && mx < startgame.x+startgame.width &&
my > startgame.y && my < startgame.y+startgame.height)
{
isStarted = true;
}
}
public void mouseMoved(MouseEvent e)
{
mhx = e.getX();
mhy = e.getY();
if(mhx > startgame.x && mhx < startgame.x+startgame.width &&
mhy > startgame.y && mhy < startgame.y+startgame.height)
isHovered = true;
else
isHovered = false;
}
});
}
public void paint(Graphics g)
{
dbi = createImage(getWidth(), getHeight());
dbg = dbi.getGraphics();
draw(dbg);
g.drawImage(dbi,0,0,this);
repaint();
}
public void draw(Graphics g)
{
if(!isStarted)
{
if(!isHovered)
g.setColor(Color.GRAY);
else
g.setColor(Color.GREEN);
g.fillRect(startgame.x, startgame.y, startgame.width, startgame.height);
g.setFont(new Font("Serif",Font.BOLD,24));
g.setColor(Color.WHITE);
g.drawString("Start game", startgame.x+20, startgame.y+25);
g.drawString(String.format("hoverx: %d hovery: %d",mhx,mhy), 50,200);
}
else
{
}
}
public void run()
{
} }
public class Game {
public static void main(String[] args)
{
Contents c = new Contents();
} }
Just use Rectangle.contains(Point) to check if the point from the MouseEvent is inside the Rectangle. Here is an example
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionAdapter;
import java.awt.geom.Rectangle2D;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class PaintedButton extends JPanel {
private static final Color HOVER_COLOR = Color.BLUE;
private static final Color NON_HOVER_COLOR = Color.GREEN;
private static final Rectangle2D RECTANGLE = new Rectangle2D.Double(50, 50,
200, 100);
private Color color = NON_HOVER_COLOR;
public PaintedButton() {
addMouseMotionListener(new MouseMotionAdapter() {
public void mouseMoved(MouseEvent e) {
Point p = e.getPoint();
if (RECTANGLE.contains(p)) {
color = HOVER_COLOR;
} else {
color = NON_HOVER_COLOR;
}
repaint();
}
});
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setPaint(color);
g2.fill(RECTANGLE);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(300, 200);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new PaintedButton());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
}