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Java issues with all my color changing and the drawing not starting when I click

I am having an issue figuring out why my code isn't working for when I click to turn the drawing on/off. It should start as off initially but it doesn't. I also have an issue with my arraylist where I am not sure how to make it so that all the colors don't change when I click on a new color. This is my code so far, any help would be much appreciated.
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Line2D;
import java.util.ArrayList;
import javax.swing.ButtonGroup;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import java.awt.event.MouseMotionAdapter;
public class Draw extends JPanel {
private Point startPoint, endPoint;
private ArrayList<Point> pointList;
private JButton clear;
private JRadioButton red, yellow, blue, eraser;
private boolean clicked;
private final static int SIZE = 30;
public Draw() {
// set the background color
setBackground(Color.WHITE);
// set starting point and end point of mouse click
startPoint = null;
endPoint = null;
this.addMouseListener(new MyMouseListener());
this.addMouseMotionListener(new MyMouseListener());
clicked = false;
pointList = new ArrayList<Point>();
this.addMouseMotionListener(new MyMouseListener());
clear = new JButton("Clear Drawing");
this.add(clear);
clear.addActionListener(new ButtonListener());
red = new JRadioButton("Red", true);
this.add(red);
red.addActionListener(new OptionListener());
yellow = new JRadioButton("Yellow", false);
this.add(yellow);
yellow.addActionListener(new OptionListener());
blue = new JRadioButton("Blue", false);
this.add(blue);
blue.addActionListener(new OptionListener());
eraser = new JRadioButton("Eraser",false);
this.add(eraser);
eraser.addActionListener(new OptionListener());
ButtonGroup group = new ButtonGroup();
group.add(red);
group.add(yellow);
group.add(blue);
group.add(eraser);
}
private class OptionListener implements ActionListener {
public void actionPerformed(ActionEvent event) {
repaint();
}
}
private class ButtonListener implements ActionListener {
public void actionPerformed(ActionEvent event) {
if (event.getSource() == clear) {
pointList.clear();
repaint();
} else {
repaint();
}
}
}
private class MyMouseListener extends MouseAdapter {
#Override
public void mouseClicked(MouseEvent event) {
if (clicked) {
pointList = new ArrayList<Point>();
pointList.add(event.getPoint());
endPoint = null;
} else {
endPoint = event.getPoint();
startPoint = null;
}
clicked = !clicked;
repaint();
}
#Override
public void mouseMoved(MouseEvent event) {
pointList.add(event.getPoint());
repaint();
}
}
#Override
public void paintComponent(Graphics pen) {
super.paintComponent(pen);
Graphics2D g2 = (Graphics2D) pen;
for (Point p : pointList) {
if (red.isSelected()) {
g2.setColor(Color.RED);
g2.fill(new Ellipse2D.Double(p.getX(), p.getY(), SIZE, SIZE));
} else if (yellow.isSelected()) {
g2.setColor(Color.YELLOW);
g2.fill(new Ellipse2D.Double(p.getX(), p.getY(), SIZE, SIZE));
} else if (blue.isSelected()) {
g2.setColor(Color.BLUE);
g2.fill(new Ellipse2D.Double(p.getX(), p.getY(), SIZE, SIZE));
} else {
}
}
}
public static void main(String args[]) {
EventQueue.invokeLater(new Runnable() {
public void run() {
JFrame frame = new JFrame("Drawing Time");
frame.setSize(500, 500);
// create an object of your class
Draw panel = new Draw();
frame.getContentPane().add(panel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}
}

I also have an issue with my arraylist where I am not sure how to make it so that all the colors dont change when I click on a new color
There are two ways to do custom painting:
paint to a BufferedImage. Using this approach the object is painted and the currently selected color will be used to paint the object
(the approach you are using) - store the object you want to paint in an ArrayList. The problem is you are only storing the Point objects in the list so all Points get repainted with the same color. If you want each Point to have a different Color, then you need to store a custom Object that contains both the Color and the Point.
Check out Custom Painting Approaches for working examples of both of these approaches.
You need to associate the Color with each individual object that you paint.

Java - Access datas of a MouseListener from another Component

I'm currently working on a level editor for a game. Currently, to create an Entity, you have to click on a creation JButton, then a form appears, where you enter its coordinate and its size.
I would like to implement a mouse fonction. The user click on the creation JButton, then have to press the mouseButton somewhere on the JPanel where the level is previewed, then drag to set the size of the object, and finally release the button. The object is then created where the button was pressed.
I add a MouseListener to the previewPanel (to get the correct coordinates).
My problem is : what should I do when I click on the button ?Inside the actionPerformed method ?
bascially, the procedure would be :
1) Wait the button to be pressed
2) get coordinates
3) Wait the button to be released
4) Get new coordinates to make the size of the object
5) Create object
How should I proceed to do it properly ?
Thanks in advance

My problem is : what should I do when I click on the button ?
Inside the actionPerformed method ?
Activate the MouseListener. This can be by adding the MouseListener and MouseMotionListener (a MouseAdapater can do both) to the drawing JPanel on button click, or by changing the state of an already added MouseAdapater (my preference), again one that has already been added to the JPanel. This could be as simple as switching a boolean variable to true, and then have the mousePressed, mouseDragged, mouseReleased methods check the state of this boolean before doing any of their actions.
Note that if you go the first route -- by adding a MouseListener/MouseMotionListener on button press, you risk adding multiple listeners if you don't take care to remove them when you're through. That is why I prefer the 2nd approach.
e.g.,
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Shape;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
public class ActivateMouse extends JPanel {
private static final int PREF_W = 400;
private static final int PREF_H = PREF_W;
private static final Color DRAW_RECT_COLOR = Color.pink.brighter();
private static final Color DRAW_ALL_RECTS_COLOR = Color.red;
private boolean mouseActive = false;
private Shape drawRect = null;
private List<Shape> shapeList = new ArrayList<>();
private ButtonAction buttonAction = new ButtonAction("Create New Rectangle", KeyEvent.VK_C);
public ActivateMouse() {
MyMouseAdapter myMouseAdapter = new MyMouseAdapter();
addMouseListener(myMouseAdapter);
addMouseMotionListener(myMouseAdapter);
add(new JButton(buttonAction));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
if (drawRect != null) {
g2.setColor(DRAW_RECT_COLOR);
g2.draw(drawRect);
}
g2.setColor(DRAW_ALL_RECTS_COLOR);
for (Shape shape : shapeList) {
g2.draw(shape);
}
}
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
private class MyMouseAdapter extends MouseAdapter {
private Point firstPt;
#Override
public void mousePressed(MouseEvent e) {
if (mouseActive && e.getButton() == MouseEvent.BUTTON1) {
firstPt = e.getPoint();
}
}
#Override
public void mouseDragged(MouseEvent e) {
if (!mouseActive || firstPt == null) {
return;
}
drawRect = createRect(e.getPoint());
repaint();
}
#Override
public void mouseReleased(MouseEvent e) {
if (!mouseActive || firstPt == null) {
return;
}
shapeList.add(createRect(e.getPoint()));
repaint();
mouseActive = false;
}
private Shape createRect(Point p) {
int x = Math.min(firstPt.x, p.x);
int y = Math.min(firstPt.y, p.y);
int width = Math.abs(firstPt.x - p.x);
int height = Math.abs(firstPt.y - p.y);
return new Rectangle(x, y, width, height);
}
}
private class ButtonAction extends AbstractAction {
public ButtonAction(String name, int mnemonic) {
super(name);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
mouseActive = true;
}
}
private static void createAndShowGui() {
JFrame frame = new JFrame("ActivateMouse");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new ActivateMouse());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}

Multiple problems regarding Java paint program while painting

I have a Java paint program, and I've got two problems to do with it. Both problems are relatively simple, and just regard how the mouse input is handled and how the image uses colors. Here's a photo of the app:
So here's my first problem:
As you can see, by the look of the app, there's a spray of dots on the paint area. Each of those dots is a mouseclick. The program does not recognize when a user is holding down the mouse button, so you have to click individually.
This is obviously counterproductive, user-unfriendly and unacceptable. Now, how I fix this, I'm not sure. I've tried using a permanent while (true) loop, but that does not work. How do I make it so that instead of having to click every time, each time the mouse is held down it sprays out dots?
The second problem is the color of the dots. As you can see, at the bottom, there are color buttons. These function, but there is a problem: Whenever I change the color, all the dots currently on the screen change color. The color is run by a variable called currentColor which is run by the actionListeners controlled by all the color buttons on the bottom panel. How do I make sure that colors already placed on the screen are not affected anymore?
I believe that all the code that can be fixed for these two problems lies in my custom JPanel which is used for the program to paint on. I'll post the entire class below, and if you have any other questions, please let me know.
int xCord, yCord;
public class PaintPanel extends JPanel implements MouseListener {
// default serial whatever...
private static final long serialVersionUID = -6514297510194472060L;
public PaintPanel() {
addMouseListener(this);
}
ArrayList<Point> points = new ArrayList<Point>();
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
for (Point point : points) {
g.setColor(currentColor);
g.fillOval(point.x, point.y, 12, 12);
}
repaint();
}
#Override
public void mouseClicked(MouseEvent m) {
}
#Override
public void mouseEntered(MouseEvent m) {
}
#Override
public void mouseExited(MouseEvent m) {
}
#Override
public void mousePressed(MouseEvent m) {
if (paintPanel.contains(m.getPoint())) {
points.add(m.getPoint());
xCord = m.getX();
yCord = m.getY();
System.out.println("x: " + xCord + " y: " + yCord);
}
}
#Override
public void mouseReleased(MouseEvent m) {
}
}

Painting in Swing is destructive.
That is to say, when Swing requests that a repaint occur on a component, the component is expected to clear what ever was previously paint and update itself.
The problem with your color issue is that you only ever have a single color specified.
A possible solution would be to paint to backing buffer (like BufferedImage) instead of relying on paintComponent.
Instead of repainting all the dots each time paintComponent is called, you would simply paint the BufferedImage instead.
As to your issue with the mouse, you need to implement a MouseMotionListener, this will allow you to detect when the mouse is dragged across the surface, painting a trail of dots
Update with very BASIC example
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class SimplePaint04 {
public static void main(String[] args) {
new SimplePaint04();
}
public SimplePaint04() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private PaintPane paintPane;
public TestPane() {
setLayout(new BorderLayout());
add((paintPane = new PaintPane()));
add(new ColorsPane(paintPane), BorderLayout.SOUTH);
}
}
public class ColorsPane extends JPanel {
public ColorsPane(PaintPane paintPane) {
add(new JButton(new ColorAction(paintPane, "Red", Color.RED)));
add(new JButton(new ColorAction(paintPane, "Green", Color.GREEN)));
add(new JButton(new ColorAction(paintPane, "Blue", Color.BLUE)));
}
public class ColorAction extends AbstractAction {
private PaintPane paintPane;
private Color color;
private ColorAction(PaintPane paintPane, String name, Color color) {
putValue(NAME, name);
this.paintPane = paintPane;
this.color = color;
}
#Override
public void actionPerformed(ActionEvent e) {
paintPane.setForeground(color);
}
}
}
public class PaintPane extends JPanel {
private BufferedImage background;
public PaintPane() {
setBackground(Color.WHITE);
setForeground(Color.BLACK);
MouseAdapter handler = new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
drawDot(e.getPoint());
}
#Override
public void mouseDragged(MouseEvent e) {
drawDot(e.getPoint());
}
};
addMouseListener(handler);
addMouseMotionListener(handler);
}
protected void drawDot(Point p) {
if (background == null) {
updateBuffer();;
}
if (background != null) {
Graphics2D g2d = background.createGraphics();
g2d.setColor(getForeground());
g2d.fillOval(p.x - 5, p.y - 5, 10, 10);
g2d.dispose();
}
repaint();
}
#Override
public void invalidate() {
super.invalidate();
updateBuffer();
}
protected void updateBuffer() {
if (getWidth() > 0 && getHeight() > 0) {
BufferedImage newBuffer = new BufferedImage(getWidth(), getHeight(), BufferedImage.TYPE_INT_RGB);
Graphics2D g2d = newBuffer.createGraphics();
g2d.setColor(Color.WHITE);
g2d.fillRect(0, 0, getWidth(), getHeight());
if (background != null) {
g2d.drawImage(background, 0, 0, this);
}
g2d.dispose();
background = newBuffer;
}
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
if (background == null) {
updateBuffer();
}
g2d.drawImage(background, 0, 0, this);
g2d.dispose();
}
}
}

Make JPanel draggable

I extended the toolbar on a mac using a JPanel (see image), but the part that is the actualy toolbar (not the JPanel) is the only part that you can click and drag. How do I allow the user to click and drag the JPanel to move the window, just like they would the toolbar
The top mm or so of the image is the actual toolbar (with the text), the rest is the JPanel (with buttons).
Here is the code for the UnifiedToolPanel, which is set to the north of the border layout in the JFrame:
package gui;
import java.awt.Color;
import java.awt.GradientPaint;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Window;
import java.awt.event.WindowEvent;
import java.awt.event.WindowFocusListener;
import java.awt.event.WindowListener;
import javax.swing.BorderFactory;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.Border;
import com.jgoodies.forms.factories.Borders;
public class UnifiedToolbarPanel extends JPanel implements WindowFocusListener {
public static final Color OS_X_UNIFIED_TOOLBAR_FOCUSED_BOTTOM_COLOR =
new Color(64, 64, 64);
public static final Color OS_X_UNIFIED_TOOLBAR_UNFOCUSED_BORDER_COLOR =
new Color(135, 135, 135);
public static final Color OS_X_TOP_FOCUSED_GRADIENT = new Color(214+8, 214+8, 214+8);
public static final Color OS_X_BOTTOM_FOCUSED_GRADIENT = new Color(217, 217, 217);
public static final Color OS_X_TOP_UNFOCUSED_GRADIENT = new Color(240+3, 240+3, 240+3);
public static final Color OS_X_BOTTOM_UNFOCUSED_GRADIENT = new Color(219, 219, 219);
public UnifiedToolbarPanel() {
// make the component transparent
setOpaque(true);
Window window = SwingUtilities.getWindowAncestor(this);
// create an empty border around the panel
// note the border below is created using JGoodies Forms
setBorder(Borders.createEmptyBorder("3dlu, 3dlu, 1dlu, 3dlu"));
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
Window window = SwingUtilities.getWindowAncestor(this);
Color color1 = window.isFocused() ? OS_X_TOP_FOCUSED_GRADIENT
: OS_X_TOP_UNFOCUSED_GRADIENT;
Color color2 = window.isFocused() ? color1.darker()
: OS_X_BOTTOM_UNFOCUSED_GRADIENT;
int w = getWidth();
int h = getHeight();
GradientPaint gp = new GradientPaint(
0, 0, color1, 0, h, color2);
g2d.setPaint(gp);
g2d.fillRect(0, 0, w, h);
}
#Override
public Border getBorder() {
Window window = SwingUtilities.getWindowAncestor(this);
return window != null && window.isFocused()
? BorderFactory.createMatteBorder(0,0,1,0,
OS_X_UNIFIED_TOOLBAR_FOCUSED_BOTTOM_COLOR)
: BorderFactory.createMatteBorder(0,0,1,0,
OS_X_UNIFIED_TOOLBAR_UNFOCUSED_BORDER_COLOR);
}
#Override
public void windowGainedFocus(WindowEvent e) {
repaint();
}
#Override
public void windowLostFocus(WindowEvent e) {
repaint();
}
}

How do I allow the user to click and drag the JPanel to move the window
Here is the way :
private int x;
private int y;
//.....
//On mouse pressed:
jpanel.addMouseListener(new MouseAdapter(){
public void mousePressed(MouseEvent ev){
x = ev.getX ();
y = ev.getY();
}
});
//....
//on mouse dragged
jpanel.addMouseMotionListener(new MouseMotionAdapter() {
public void mouseDragged(MouseEvent evt) {
int x = evt.getXOnScreen()-this.x;
int y = evt.getYOnScreen -this.y;
this.setLocation(x,y);
}
});
this.setLocation(x,y) will moves the Frame not the panel, I thought that your class extended JFrame.
However, you can create a method that returns a point (x,y) and set it to the window.

There wasn't really an answer with the Point class so I will be adding my contribution instead of storing the x, y cords of the MouseEvent, We store the Point
Here is show you can do it, Define a global Variable of the Class java.awt.Point
private Point currentLocation;
we then store the point to currentLocation once mouse is pressed using MouseListener
panel.addMouseListener(new MouseAdapter() {
public void mousePressed(MouseEvent e) {
currentLocation = e.getPoint();
}
});
and we set the JFrame location when mouse is dragged using MouseMotionListener
panel.addMouseMotionListener(new MouseAdapter() {
public void mouseDragged(MouseEvent e) {
Point currentScreenLocation = e.getLocationOnScreen();
setLocation(currentScreenLocation.x - currentLocation.x, currentScreenLocation.y - currentLocation.y);
}
});
and we put all the code together inside a HelperMethod to be used anywhere
public void setDraggable(JPanel panel) {
panel.addMouseListener(new MouseAdapter() {
public void mousePressed(MouseEvent e) {
currentLocation = e.getPoint();
}
});
panel.addMouseMotionListener(new MouseAdapter() {
public void mouseDragged(MouseEvent e) {
Point currentScreenLocation = e.getLocationOnScreen();
setLocation(currentScreenLocation.x - currentLocation.x, currentScreenLocation.y - currentLocation.y);
}
});
}
I store my HelperMethod in a class that extends JFrame Hence why I have access to setLocation that belongs to JFrame without a variable.

Dragging of shapes on Jpanel

I am using JButton's Action listener to draw different shapes.To keep previously drawn shapes on panel all time, I've used an arraylist in which all drawn shapes has added and repaint whole list.How can I drag any shape while others display on Jpanel all the time?
protected void paintComponent(Graphics g) {
super.paintComponent(g);
System.out.println("====>>> " + s);
switch (s) {
case "Button1":
Activity act = new Activity();
act.setArcH(15);
act.setArcW(15);
act.setBreadth(40);
act.setLength(50);
act.setXpoint(x);
act.setYpoint(y);
//==========================================================
obj = new ShapePoints();
obj.setShapeId(ShapesID.ROUND_RECTANGLE_ID);
obj.setxPoint(act.getXpoint());
obj.setyPoint(act.getYpoint());
obj.setLength(act.getLength());
obj.setBreadth(act.getBreadth());
obj.setArcW(act.getArcW());
obj.setArcH(act.getArcH());
shapePoints.add(obj);
Iterator itr = shapePoints.iterator();
while (itr.hasNext()) {
ShapePoints sp = (ShapePoints) itr.next();
switch (sp.getShapeId()) {
case ShapesID.ARROW_ID:
break;
case ShapesID.CIRCLE_ID:
g.drawOval(obj.getxPoint(), obj.getyPoint(), obj.getLength(), obj.getBreadth());
break;
case ShapesID.CON_CIRCLE_ID:
g.drawOval(sp.getxPoint(), sp.getyPoint(), sp.getLength(), sp.getLength());
g.fillOval(sp.getxPoint() + 10, sp.getyPoint() + 10, sp.getBreadth() / 2, sp.getBreadth() / 2);
break;
case ShapesID.RECTANGLE_ID:
break;
case ShapesID.ROUND_RECTANGLE_ID:
g.drawRoundRect(obj.getxPoint(), obj.getyPoint(), obj.getLength(), obj.getBreadth(),
obj.getArcW(), obj.getArcH());
break;
}
}
break;
this is for 1 button

You need to add a mouselistener and a mousemotionlistener (usually you make a single instance for both) and check wheter your shape contains the mouse pressed event or not. If yes, you keep track of where the mouse is dragged to translate your shape and continuously call repaint(), like usual.
Single click creates a vertex of a polygon
Double click creates the current drawn polygon (if it has at least 3 vertices) and we create a new one
Right-click clears the current drawn polygon and creates a new one
Press/Drag/Release moves the polygon located under the mouse (if there are several, it takes the first one found. it would probably better to make a reverse for-loop)
Here is an example:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.Polygon;
import java.awt.event.MouseAdapter;
import java.awt.geom.Rectangle2D;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class TestNaming {
private static final int PANEL_WIDTH = 600;
private static final int PANEL_HEIGHT = 600;
public static class Drawing extends JPanel {
private static final Font FONT = new Font("Arial", Font.PLAIN, 12);
private List<Polygon> polygons = new ArrayList<Polygon>();
private Polygon currentPolygon = new Polygon();
private MouseAdapter mouseListener = new MouseAdapter() {
private Polygon dragged;
private Point lastLocation;
#Override
public void mousePressed(java.awt.event.MouseEvent e) {
for (Polygon p : polygons) {
if (p.contains(e.getPoint())) {
dragged = p;
lastLocation = e.getPoint();
break;
}
}
}
#Override
public void mouseDragged(java.awt.event.MouseEvent e) {
if (dragged != null) {
dragged.translate(e.getX() - lastLocation.x, e.getY() - lastLocation.y);
lastLocation = e.getPoint();
repaint();
}
}
#Override
public void mouseReleased(java.awt.event.MouseEvent e) {
dragged = null;
lastLocation = null;
}
#Override
public void mouseClicked(java.awt.event.MouseEvent e) {
if (SwingUtilities.isLeftMouseButton(e)) {
if (e.getClickCount() == 1) {
addPoint(e.getX(), e.getY());
} else if (e.getClickCount() == 2) {
createPolygon();
}
} else if (SwingUtilities.isRightMouseButton(e)) {
clearCurrentPolygon();
}
}
};
public Drawing() {
addMouseListener(mouseListener);
addMouseMotionListener(mouseListener);
}
protected void addPoint(int x, int y) {
currentPolygon.addPoint(x, y);
repaint();
}
protected void clearCurrentPolygon() {
currentPolygon = new Polygon();
repaint();
}
protected void createPolygon() {
if (currentPolygon.npoints > 2) {
polygons.add(currentPolygon);
}
clearCurrentPolygon();
repaint();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(PANEL_WIDTH, PANEL_HEIGHT);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.RED);
g.setFont(FONT);
for (Polygon polygon : polygons) {
drawPolygon(g, polygon);
}
g.setColor(Color.GREEN);
drawPolygon(g, currentPolygon);
}
private void drawPolygon(Graphics g, Polygon polygon) {
if (polygon.npoints < 3) {
if (polygon.npoints == 1) {
g.fillOval(polygon.xpoints[0] - 2, polygon.ypoints[0] - 2, 4, 4);
drawNthPoint(g, polygon, 0);
} else if (polygon.npoints == 2) {
g.drawLine(polygon.xpoints[0], polygon.ypoints[0], polygon.xpoints[1], polygon.ypoints[1]);
drawNthPoint(g, polygon, 0);
drawNthPoint(g, polygon, 1);
}
} else {
g.drawPolygon(polygon);
for (int i = 0; i < polygon.npoints; i++) {
drawNthPoint(g, polygon, i);
}
}
}
private void drawNthPoint(Graphics g, Polygon polygon, int nth) {
// Only works 26 times!
String name = Character.toString((char) ('A' + nth));
int x = polygon.xpoints[nth];
int height = g.getFontMetrics().getHeight();
int y = polygon.ypoints[nth] < height ? polygon.ypoints[nth] + height : polygon.ypoints[nth];
Rectangle2D stringBounds = g.getFontMetrics().getStringBounds(name, g);
g.drawString(name, x, y);
}
}
protected static void initUI() {
JFrame frame = new JFrame("test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new Drawing());
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
initUI();
}
});
}
}