I have a Class Circle with a button and a Class with a jPanel what i want to do is when that button is clicked a circle will be drawn on the panel and each time i click that button and change x and y "some how not implemented here" i got a circle on the JPanel over and over . How to do that, or is there a way to do what i descriped regardless of my code but i want the class circle to extends Shape.
public class Window{
private JFrame frame;
private JPanel panel = new JPanel();
Circle c = new Circle(frame, panel);
// some other buttons
.
.
// some code to set the panel grid bag constaraints and background then
frame.getContentPane().add(panel, gbc_panel);
}
then the Circle Class
public class Circle extends Shape implements ActionListener{
private JPanel Panel;
private GridBagConstraints gbc_btnCircle;
private JButton btnCircle;
public void setPanel(JPanel panel) {
Panel = panel;
}
public Circle(JFrame frame, JPanel panel){
btnCircle = new JButton("Circle");
// some code to set grid bag constraint then
frame.getContentPane().add(btnCircle, gbc_btnCircle);
setPanel(panel);
btnCircle.addActionListener(this);
}
public void paint(Graphics g) {
super.paintComponents(g);
g.setColor(Color.red);
g.fillOval(100, 100, 100, 100);
Panel.add(this);
}
public void actionPerformed(ActionEvent arg0) {
repaint();
}
}
You kinda have the wrong idea. In your drawing panel, you should have a List<Circle>
. And in the paintComponent
method of the drawing panel, you should iterate through the list to draw each circle
class Circle {
int x, int y, int width, int height;
public Circle (int x, int y, int width, int height) {
... set em
}
public void draw(Graphics g) {
g.fillOval(x, y, width, height);
}
}
class DrawingPanel extends JPanel {
List<Circle> circles = new ArrayList<>();
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
for (Circle circle : circles) {
circle.draw(g);
}
}
// Dont forget to override public Dimension getPreferredSize()
}
To add more Circles to the list, just have a addCircle
method in the DrawingPanel
class
public void addCircle(Circle circle) {
circles.add(circle);
repaint();
}
As far as the button, you should be creating it in the Window
class. In the ActionListener
, just create a new Circle
and add it the DrawingPanel
by calling the addCircle
method
An aside, Circle
doesn't need the extend Shape
. The Shape
API already has an Ellipse2D
class, which you can create circles from
class DrawingPanel extends JPanel {
List<Ellipse2D> circles = new ArrayList<>();
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g.create();
for (Ellipse2D circle : circles) {
g2.fill(circle);
}
g2.dispose();
}
// Dont forget to override public Dimension getPreferredSize()
}
UPDATE: full example
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class CirclesDemo {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable(){
public void run() {
new CirclesDemo();
}
});
}
public CirclesDemo() {
JFrame frame = new JFrame();
frame.add(panel);
frame.add(createButton(), BorderLayout.PAGE_END);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
private final DrawingPanel panel = new DrawingPanel();
private JButton createButton() {
JButton button = new JButton("Add Circle");
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
int[] circleValues = generateRandomValues(300, 300, 50, 150);
int x = circleValues[0];
int y = circleValues[1];
int width = circleValues[2];
int height = width;
Circle circle = new Circle(x, y, width, height);
panel.addCircle(circle);
}
});
return button;
}
private int[] generateRandomValues(int maxX, int maxY,
int minSize, int maxSize) {
Random random = new Random();
int[] values = new int[3];
values[0] = random.nextInt(maxX);
values[1] = random.nextInt(maxY);
values[2] = Math.min(random.nextInt(maxSize) + minSize, maxSize);
return values;
}
class Circle {
int x, y, width, height;
public Circle(int x, int y, int width, int height) {
this.x = x;
this.y = y;
this.width = width;
this.height = height;
}
public void draw(Graphics g) {
g.drawOval(x, y, width, height);
}
}
class DrawingPanel extends JPanel {
List<Circle> circles = new ArrayList<>();
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
for (Circle circle : circles) {
circle.draw(g);
}
}
public void addCircle(Circle circle) {
circles.add(circle);
repaint();
}
@Override
public Dimension getPreferredSize() {
return new Dimension(400, 400);
}
}
}
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With