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How to draw a arrow with java2d?

I'm trying to draw an arrow in a circle(like a clock pointer), but I can't align the tip of the arrow with the rest of the line.
I made the "arrow" based on this answer, but I can't make it is correctly positioned with the line drawing.
The arrow is more to the left of the line, as follows in the image:
Here my mcve:
import java.awt.BasicStroke;
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.Polygon;
import java.awt.geom.AffineTransform;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
public class LineArrowTest extends JFrame {
private static final long serialVersionUID = 1L;
private JPanel contentPane;
private JPanel DrawPanel;
public static void main(String[] args) {
EventQueue.invokeLater(() -> {
new LineArrowTest().setVisible(true);
});
}
public LineArrowTest() {
initComponents();
pack();
}
private void initComponents() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setPreferredSize(new Dimension(400, 300));
this.contentPane = new JPanel(new BorderLayout(0, 0));
this.contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(this.contentPane);
this.DrawPanel = new JPanel() {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
LineArrow line = new LineArrow(getWidth() / 2, getHeight() / 2, getWidth() / 2, getHeight(),
Color.black, 3);
line.draw(g);
}
};
this.contentPane.add(this.DrawPanel, BorderLayout.CENTER);
}
class LineArrow {
int x;
int y;
int endX;
int endY;
Color color;
int thickness;
public LineArrow(int x, int y, int x2, int y2, Color color, int thickness) {
super();
this.x = x;
this.y = y;
this.endX = x2;
this.endY = y2;
this.color = color;
this.thickness = thickness;
}
public void draw(Graphics g) {
Graphics2D g2 = (Graphics2D) g.create();
g2.setColor(color);
g2.setStroke(new BasicStroke(thickness));
g2.drawLine(x, y, endX, endY);
;
drawArrowHead(g2);
g2.dispose();
}
private void drawArrowHead(Graphics2D g2) {
Polygon arrowHead = new Polygon();
AffineTransform tx = new AffineTransform();
arrowHead.addPoint(0, 5);
arrowHead.addPoint(-5, -5);
arrowHead.addPoint(5, -5);
tx.setToIdentity();
double angle = Math.atan2(endY - y, endX - x);
tx.translate(endX, endY);
tx.rotate(angle - Math.PI / 2d);
g2.setTransform(tx);
g2.fill(arrowHead);
}
}
}

You are resetting the transformation.
Change AffineTransform tx = new AffineTransform(); to AffineTransform tx = g2.getTransform(); and remove the tx.setToIdentity(); call.
The below code was also rearranged to keep related statements together.
private void drawArrowHead(Graphics2D g2) {
double angle = Math.atan2(endY - y, endX - x);
AffineTransform tx = g2.getTransform();
tx.translate(endX, endY);
tx.rotate(angle - Math.PI / 2d);
g2.setTransform(tx);
Polygon arrowHead = new Polygon();
arrowHead.addPoint(0, 5);
arrowHead.addPoint(-5, -5);
arrowHead.addPoint(5, -5);
g2.fill(arrowHead);
}

How should I make the RoundedBorder background transparent? [duplicate]

The following screenshot shows a test of TextBubbleBorder1. I would like to make the corners of the component that are outside the rectangle to be entirely transparent & show whatever component is beneath it. I found a way to restrict the BG color of a label to 'inside the border' by setting a Clip (representing the area outside the rounded corners) on the Graphics2D instance and calling clearRect(). That can be seen in Label 1.
However you can see the downside of this approach when there is a red BG (or any non-standard color) on the parent panel. The corners default to the default panel color (easiest to see in Panel 2).
Ultimately I would like this to work for a non-standard color in the parent container, but it was partly inspired by What do I need to do to replicate this component with gradient paint?
Does anybody know a way to get those corners transparent?
import java.awt.*;
import java.awt.geom.*;
import javax.swing.*;
import javax.swing.border.*;
public class BorderTest {
public static void main(String[] args) {
Runnable r = new Runnable() {
#Override
public void run() {
JPanel gui = new JPanel(new GridLayout(1,0,5,5));
gui.setBorder(new EmptyBorder(10,10,10,10));
gui.setBackground(Color.RED);
AbstractBorder brdr = new TextBubbleBorder(Color.BLACK,2,16,0);
JLabel l1 = new JLabel("Label 1");
l1.setBorder(brdr);
gui.add(l1);
JLabel l2 = new JLabel("Label 2");
l2.setBorder(brdr);
l2.setBackground(Color.YELLOW);
l2.setOpaque(true);
gui.add(l2);
JPanel p1 = new JPanel();
p1.add(new JLabel("Panel 1"));
p1.setBorder(brdr);
p1.setOpaque(false);
gui.add(p1);
JPanel p2 = new JPanel();
p2.add(new JLabel("Panel 2"));
p2.setBorder(brdr);
gui.add(p2);
JOptionPane.showMessageDialog(null, gui);
}
};
// Swing GUIs should be created and updated on the EDT
// http://docs.oracle.com/javase/tutorial/uiswing/concurrency/initial.html
SwingUtilities.invokeLater(r);
}
}
class TextBubbleBorder extends AbstractBorder {
private Color color;
private int thickness = 4;
private int radii = 8;
private int pointerSize = 7;
private Insets insets = null;
private BasicStroke stroke = null;
private int strokePad;
private int pointerPad = 4;
RenderingHints hints;
TextBubbleBorder(
Color color) {
new TextBubbleBorder(color, 4, 8, 7);
}
TextBubbleBorder(
Color color, int thickness, int radii, int pointerSize) {
this.thickness = thickness;
this.radii = radii;
this.pointerSize = pointerSize;
this.color = color;
stroke = new BasicStroke(thickness);
strokePad = thickness / 2;
hints = new RenderingHints(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
int pad = radii + strokePad;
int bottomPad = pad + pointerSize + strokePad;
insets = new Insets(pad, pad, bottomPad, pad);
}
#Override
public Insets getBorderInsets(Component c) {
return insets;
}
#Override
public Insets getBorderInsets(Component c, Insets insets) {
return getBorderInsets(c);
}
#Override
public void paintBorder(
Component c,
Graphics g,
int x, int y,
int width, int height) {
Graphics2D g2 = (Graphics2D) g;
int bottomLineY = height - thickness - pointerSize;
RoundRectangle2D.Double bubble = new RoundRectangle2D.Double(
0 + strokePad,
0 + strokePad,
width - thickness,
bottomLineY,
radii,
radii);
Polygon pointer = new Polygon();
// left point
pointer.addPoint(
strokePad + radii + pointerPad,
bottomLineY);
// right point
pointer.addPoint(
strokePad + radii + pointerPad + pointerSize,
bottomLineY);
// bottom point
pointer.addPoint(
strokePad + radii + pointerPad + (pointerSize / 2),
height - strokePad);
Area area = new Area(bubble);
area.add(new Area(pointer));
g2.setRenderingHints(hints);
Area spareSpace = new Area(new Rectangle(0, 0, width, height));
spareSpace.subtract(area);
g2.setClip(spareSpace);
g2.clearRect(0, 0, width, height);
g2.setClip(null);
g2.setColor(color);
g2.setStroke(stroke);
g2.draw(area);
}
}
While the TextBubbleBorder was devised for Internal padding for JTextArea with background Image (& ended up using a JLabel since the text area was a mess for the reasons mentioned above), by specifying a pointerSize of 0 we end up with a 'rounded rectangle' instead.

N.B. There is a clipping bug in this code, which is fixed in the accepted answer to paintComponent() is drawing on other components. This should only be considered as a solution if the 'clipping bug fix' is incorporated.
// Paint the BG color of the parent, everywhere outside the clip
// of the text bubble.
See this point in the code for the source that shows correctly as:
import java.awt.*;
import java.awt.image.*;
import java.awt.geom.*;
import javax.swing.*;
import javax.swing.border.*;
public class BorderTest {
public static void main(String[] args) {
Runnable r = new Runnable() {
#Override
public void run() {
JPanel gui = new JPanel(new GridLayout(2,0,5,5));
gui.setBorder(new EmptyBorder(10,10,10,10));
gui.setBackground(Color.RED);
AbstractBorder brdrLeft = new TextBubbleBorder(Color.BLACK,2,16,16);
AbstractBorder brdrRight = new TextBubbleBorder(Color.BLACK,2,16,16,false);
JLabel l1 = new JLabel("Label 1");
l1.setBorder(brdrRight);
gui.add(l1);
JLabel l2 = new JLabel("Label 2");
l2.setBorder(brdrLeft);
l2.setBackground(Color.YELLOW);
l2.setOpaque(true);
gui.add(l2);
JPanel p1 = new JPanel();
p1.add(new JLabel("Panel 1"));
p1.setBorder(brdrRight);
p1.setOpaque(false);
gui.add(p1);
JPanel p2 = new JPanel();
p2.add(new JLabel("Panel 2"));
p2.setBorder(brdrLeft);
gui.add(p2);
JOptionPane.showMessageDialog(null, gui);
}
};
// Swing GUIs should be created and updated on the EDT
// http://docs.oracle.com/javase/tutorial/uiswing/concurrency/initial.html
SwingUtilities.invokeLater(r);
}
}
class TextBubbleBorder extends AbstractBorder {
private Color color;
private int thickness = 4;
private int radii = 8;
private int pointerSize = 7;
private Insets insets = null;
private BasicStroke stroke = null;
private int strokePad;
private int pointerPad = 4;
private boolean left = true;
RenderingHints hints;
TextBubbleBorder(
Color color) {
this(color, 4, 8, 7);
}
TextBubbleBorder(
Color color, int thickness, int radii, int pointerSize) {
this.thickness = thickness;
this.radii = radii;
this.pointerSize = pointerSize;
this.color = color;
stroke = new BasicStroke(thickness);
strokePad = thickness / 2;
hints = new RenderingHints(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
int pad = radii + strokePad;
int bottomPad = pad + pointerSize + strokePad;
insets = new Insets(pad, pad, bottomPad, pad);
}
TextBubbleBorder(
Color color, int thickness, int radii, int pointerSize, boolean left) {
this(color, thickness, radii, pointerSize);
this.left = left;
}
#Override
public Insets getBorderInsets(Component c) {
return insets;
}
#Override
public Insets getBorderInsets(Component c, Insets insets) {
return getBorderInsets(c);
}
#Override
public void paintBorder(
Component c,
Graphics g,
int x, int y,
int width, int height) {
Graphics2D g2 = (Graphics2D) g;
int bottomLineY = height - thickness - pointerSize;
RoundRectangle2D.Double bubble = new RoundRectangle2D.Double(
0 + strokePad,
0 + strokePad,
width - thickness,
bottomLineY,
radii,
radii);
Polygon pointer = new Polygon();
if (left) {
// left point
pointer.addPoint(
strokePad + radii + pointerPad,
bottomLineY);
// right point
pointer.addPoint(
strokePad + radii + pointerPad + pointerSize,
bottomLineY);
// bottom point
pointer.addPoint(
strokePad + radii + pointerPad + (pointerSize / 2),
height - strokePad);
} else {
// left point
pointer.addPoint(
width - (strokePad + radii + pointerPad),
bottomLineY);
// right point
pointer.addPoint(
width - (strokePad + radii + pointerPad + pointerSize),
bottomLineY);
// bottom point
pointer.addPoint(
width - (strokePad + radii + pointerPad + (pointerSize / 2)),
height - strokePad);
}
Area area = new Area(bubble);
area.add(new Area(pointer));
g2.setRenderingHints(hints);
// Paint the BG color of the parent, everywhere outside the clip
// of the text bubble.
Component parent = c.getParent();
if (parent!=null) {
Color bg = parent.getBackground();
Rectangle rect = new Rectangle(0,0,width, height);
Area borderRegion = new Area(rect);
borderRegion.subtract(area);
g2.setClip(borderRegion);
g2.setColor(bg);
g2.fillRect(0, 0, width, height);
g2.setClip(null);
}
g2.setColor(color);
g2.setStroke(stroke);
g2.draw(area);
}
}

Try this:
JPanel p = new JPanel() {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Dimension arcs = new Dimension(15,15); //Border corners arcs {width,height}, change this to whatever you want
int width = getWidth();
int height = getHeight();
Graphics2D graphics = (Graphics2D) g;
graphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
//Draws the rounded panel with borders.
graphics.setColor(getBackground());
graphics.fillRoundRect(0, 0, width-1, height-1, arcs.width, arcs.height);//paint background
graphics.setColor(getForeground());
graphics.drawRoundRect(0, 0, width-1, height-1, arcs.width, arcs.height);//paint border
}
};
With my test:
JFrame f = new JFrame();
f.setLayout(null);
f.setDefaultCloseOperation(3);
f.setSize(500, 500);
JPanel p = new JPanel() {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Dimension arcs = new Dimension(15,15);
int width = getWidth();
int height = getHeight();
Graphics2D graphics = (Graphics2D) g;
graphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
//Draws the rounded opaque panel with borders.
graphics.setColor(getBackground());
graphics.fillRoundRect(0, 0, width-1, height-1, arcs.width, arcs.height);//paint background
graphics.setColor(getForeground());
graphics.drawRoundRect(0, 0, width-1, height-1, arcs.width, arcs.height);//paint border
}
};
p.setBounds(10,10,100,30);
p.setOpaque(false);
f.getContentPane().setBackground(Color.red);
f.add(p);
f.show();
the result is:

Thanks #BackSlash, nice and simple. I expanded upon this so it's more reusable. This also allows setting a background color in the constructor. And I show how you can make a circular panel for fun.
import java.awt.*;
import javax.swing.*;
public class RoundedPanelExample extends JFrame
{
public RoundedPanelExample()
{
setDefaultCloseOperation(EXIT_ON_CLOSE);
setTitle("Rounded Panel Example");
setResizable(true);
setDefaultLookAndFeelDecorated(true);
setSize(500, 500);
Container pane = getContentPane();
pane.setLayout(null);
pane.setBackground(Color.LIGHT_GRAY);
JPanel p1 = new RoundedPanel(10, Color.CYAN);
p1.setBounds(10,10,100,60);
p1.setOpaque(false);
pane.add(p1);
JPanel p2 = new RoundedPanel(15, Color.RED);
p2.setBounds(150,10,50,50);
p2.setOpaque(false);
pane.add(p2);
JPanel p3 = new RoundedPanel(30);
p3.setBounds(230,10,100,150);
p3.setOpaque(false);
pane.add(p3);
JPanel p4 = new RoundedPanel(20);
p4.setBounds(10,200,100,100);
p4.setBackground(Color.GREEN);
p4.setOpaque(false);
pane.add(p4);
JPanel p5 = new RoundedPanel(200);
p5.setBounds(150,200,200,200);
p5.setBackground(Color.BLUE);
p5.setOpaque(false);
pane.add(p5);
}
public static void main(String[] args)
{
RoundedPanelExample gui = new RoundedPanelExample();
gui.setVisible(true);
}
class RoundedPanel extends JPanel
{
private Color backgroundColor;
private int cornerRadius = 15;
public RoundedPanel(LayoutManager layout, int radius) {
super(layout);
cornerRadius = radius;
}
public RoundedPanel(LayoutManager layout, int radius, Color bgColor) {
super(layout);
cornerRadius = radius;
backgroundColor = bgColor;
}
public RoundedPanel(int radius) {
super();
cornerRadius = radius;
}
public RoundedPanel(int radius, Color bgColor) {
super();
cornerRadius = radius;
backgroundColor = bgColor;
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Dimension arcs = new Dimension(cornerRadius, cornerRadius);
int width = getWidth();
int height = getHeight();
Graphics2D graphics = (Graphics2D) g;
graphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
//Draws the rounded panel with borders.
if (backgroundColor != null) {
graphics.setColor(backgroundColor);
} else {
graphics.setColor(getBackground());
}
graphics.fillRoundRect(0, 0, width-1, height-1, arcs.width, arcs.height); //paint background
graphics.setColor(getForeground());
graphics.drawRoundRect(0, 0, width-1, height-1, arcs.width, arcs.height); //paint border
}
}
}

Possible cheaper alternative
public class RoundedLabel extends JLabel {
private final Rectangle rv = new Rectangle();
#Override
public void updateUI() {
super.updateUI();
setBorder(new EmptyBorder(1, 3, 1, 3));
}
#Override
protected void paintComponent(Graphics g) {
getBounds(rv);
var g2 = (Graphics2D) g;
g2.setColor(getBackground());
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.fillRoundRect(rv.x, rv.y, rv.width, rv.height, 8, 8);
super.paintComponent(g);
}
}

Swing - irregular shaped border

I'm newbie in the swing and have a question how better to draw this shape:
I thought in two ways
to draw regular rectangle and to write custom border to it?
to draw regular rectangle + compound border(which contains 2 or 3 borders). But here i do not succeed to draw border inside the shape, is is possible at all? Something like this :
figure.setBorder(BorderFactory.createCompoundBorder(BorderFactory.createMatteBor‌​der(outside top,left,bottom, right, Color.WHITE), createMatteBorder(inside top,left,bottom, right, Color.WHITE)), where the inside border is small rectangle, and outside is big rectangle - not sure if it is possible???
Please advise and an examples will be highly appreciated!

Take a look at the Java 2D API. It helps you to draw complex shapes.
E.g.
class IrregularShape extends JComponent {
private int strokeWidth;
IrregularShape(int strokeWidth){
this.strokeWidth = strokeWidth;
}
#Override
protected void paintComponent(Graphics g) {
Graphics2D newGraphics = (Graphics2D) g.create();
Insets borderInsets = new Insets(0, 0, 0, 0);
Border border = getBorder();
if (border != null) {
borderInsets = border.getBorderInsets(this);
}
BasicStroke basicStroke = new BasicStroke(strokeWidth);
newGraphics.setStroke(basicStroke);
int x = getX() + borderInsets.left + strokeWidth;
int y = getY() + borderInsets.top + strokeWidth;
int width = getWidth() - x - borderInsets.right - strokeWidth;
int height = getHeight() - y - borderInsets.bottom - strokeWidth;
Double outterRactangleDouble = new Rectangle2D.Double(x, y, width, height);
Area outterRectangle = new Area(outterRactangleDouble);
Area innerRectangle = new Area(outterRactangleDouble);
AffineTransform affineTransform = new AffineTransform();
affineTransform.scale(0.5, 0.5);
affineTransform.translate(x + width * 0.10, y + height * 1.2);
innerRectangle.transform(affineTransform);
outterRectangle.subtract(innerRectangle);
newGraphics.draw(outterRectangle);
}
}
public class MainFrame {
public static void main(String[] args) {
JFrame frame = new JFrame("Irregular Shape");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
Container contentPane = frame.getContentPane();
contentPane.add(new IrregularShape(3));
frame.setSize(640, 150);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
Result
and it's also resizeable

you can use the polygon class (java.awt.Polygon)
int xs = new int[]{1,2,3...7}; //your x-coordinates
int ys = new int[]{1,2,3...7}; //your y-coordinates
Shape irr = new Polygon(xs, ys, xs.length);
if you want to use certain borders you can use Graphics2D
public void paintComponent(Graphics gr){
Graphics2D g2d = (Graphics2D)gr;
GradientPaint redToWhite = new GradientPaint(0,0,color.RED,100, 0,color.WHITE);
g2d.setPaint(redtowhite)
g2d.fill(irr); //fill special color
Stroke customBorder = getCustomBorder();
g2d.setStroke(customBorder);
g2d.draw(irr); //draw 'special' borders
}
have a look at stroke and fill
note that Polygon implements the contains(double x, double y)method which lets you detect if you're inside or not

You could use a Area for example...
public class TestPane extends JPanel {
public TestPane() {
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
Area area = new Area(new Rectangle(10, 10, getWidth() - 20, getHeight() - 20));
area.subtract(new Area(new Rectangle(20, getHeight() / 2, getWidth() / 2, getHeight() - 10)));
g2d.draw(area);
g2d.dispose();
}
}
You define a custom shape...
public class TestPane extends JPanel {
public TestPane() {
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
Path2D path = new Path2D.Float();
path.moveTo(10, 10);
path.lineTo(getWidth() - 20, 10);
path.lineTo(getWidth() - 20, getHeight() - 20);
path.lineTo(getWidth() / 2, getHeight() - 20);
path.lineTo(getWidth() / 2, getHeight() / 2);
path.lineTo(20, getHeight() / 2);
path.lineTo(20, getHeight() - 20);
path.lineTo(10, getHeight() - 20);
path.closePath();
g2d.draw(path);
g2d.dispose();
}
}
Actually writing a custom border would be very, very difficult, because of the irregular style of shape, where would the components actually be contained?
It might be possible to create two or more borders, which could then be laid out so that the appeared as one
See Working with Geometry for more details
Updated with Border example...
Getting a Border to actually work is far more difficult, as the expectation is that the internal area of the border will be rectangular.
Based on the complex shape you've provided, one solution would be to actually create two borders, a left and right borer, which take care of generating a "safe" area for components to be laid out within, for example:
public class LeftBorder implements Border {
private int offset;
public LeftBorder(int offset) {
this.offset = offset;
}
#Override
public void paintBorder(Component c, Graphics g, int x, int y, int width, int height) {
Path2D path = new Path2D.Float();
int xOffset = x + offset;
int yOffset = y + offset;
width -= offset;
height -= offset * 2;
float gap = width * 0.1f;
path.moveTo(xOffset, yOffset);
path.lineTo(xOffset + width, yOffset);
path.moveTo(xOffset, yOffset);
path.lineTo(xOffset, yOffset + height);
path.lineTo(xOffset + gap, yOffset + height);
path.lineTo(xOffset + gap, yOffset + (height - (height / 2)));
path.lineTo(xOffset + width, yOffset + (height - (height / 2)));
((Graphics2D)g).draw(path);
}
#Override
public Insets getBorderInsets(Component c) {
int height = c.getHeight();
height -= (height / 2);
System.out.println(height);
return new Insets(offset + 4, offset + 4, height + 4, 0);
}
#Override
public boolean isBorderOpaque() {
return false;
}
}
public class RightBorder implements Border {
private int offset;
public RightBorder(int offset) {
this.offset = offset;
}
#Override
public void paintBorder(Component c, Graphics g, int x, int y, int width, int height) {
Path2D path = new Path2D.Float();
int xOffset = x;
int yOffset = y + offset;
width -= offset;
height -= offset * 2;
path.moveTo(xOffset, yOffset);
path.lineTo(xOffset + width, yOffset);
path.lineTo(xOffset + width, yOffset + height);
path.lineTo(xOffset, yOffset + height);
path.lineTo(xOffset, yOffset + (height - (height / 2)));
((Graphics2D)g).draw(path);
}
#Override
public Insets getBorderInsets(Component c) {
return new Insets(offset + 4, 0, offset + 4, offset + 4);
}
#Override
public boolean isBorderOpaque() {
return false;
}
}
This would then require you to provide at least two panels of equal height, for example:
import java.awt.Component;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.geom.Path2D;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.Border;
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.setLayout(new GridBagLayout());
frame.add(new LeftPane());
frame.add(new RightPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class RightPane extends JPanel {
public RightPane() {
setBorder(new RightBorder(10));
setLayout(new GridBagLayout());
add(new JLabel("Righty"));
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
public class LeftPane extends JPanel {
public LeftPane() {
setBorder(new LeftBorder(10));
setLayout(new GridBagLayout());
add(new JLabel("Lefty"));
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
}
This will also be relient on the layout manager been able to layout the two components next to each other

In addition to my first answer https://stackoverflow.com/a/34287251/974186
You can also implement it as a Border.
class IrregularBorder implements Border {
private int thickness;
public IrregularBorder(int thickness) {
this.thickness = thickness;
}
#Override
public void paintBorder(Component c, Graphics g, int x, int y, int width,
int height) {
Graphics2D graphics2d = (Graphics2D) g;
BasicStroke basicStroke = new BasicStroke(thickness);
graphics2d.setStroke(basicStroke);
int halfThickness = thickness / 2;
Double outterRactangleDouble = new Rectangle2D.Double(
x + halfThickness, y + halfThickness, width - thickness,
height - thickness);
Area outterRectangle = new Area(outterRactangleDouble);
Area innerRectangle = computeInnerRect(x, y, width, height,
outterRactangleDouble);
outterRectangle.subtract(innerRectangle);
graphics2d.draw(outterRectangle);
}
private Area computeInnerRect(int x, int y, int width, int height,
Double outterRactangleDouble) {
Area innerRectangle = new Area(outterRactangleDouble);
AffineTransform affineTransform = new AffineTransform();
affineTransform.scale(0.5, 0.5);
affineTransform.translate(x + width * 0.10, y + height * 1.2);
innerRectangle.transform(affineTransform);
return innerRectangle;
}
#Override
public Insets getBorderInsets(Component c) {
int left = (int) (thickness + (c.getWidth() * 0.6));
return new Insets(thickness, left, thickness, thickness);
}
#Override
public boolean isBorderOpaque() {
return true;
}
}
and use it as usual
public class MainFrame {
public static void main(String[] args) {
JFrame frame = new JFrame("Irregular Shape");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
Container contentPane = frame.getContentPane();
JPanel mainPanel = new JPanel(new BorderLayout());
mainPanel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
contentPane.add(mainPanel);
JPanel irregularShapeBorderedPanel = new JPanel(new BorderLayout());
irregularShapeBorderedPanel.add(new JButton("Button"),
BorderLayout.CENTER);
irregularShapeBorderedPanel.setBorder(new IrregularBorder(2));
mainPanel.add(irregularShapeBorderedPanel);
frame.setSize(640, 150);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}

Get mouse detection with a dynamic shape

Basically I'm constructing a world map. I know how to have a square click area. But I'd like to make it so I can put the countries together and be able to click on the country. Now it's pretty obvious that I can't use square click areas for that because I'd have overlapping click areas. Could I do it by looking at the transparency of each pixel? Even so I don't know how to do that?

Use Shape.contains(Point2D) - something like this:
This example uses overlapping ellipses to show how the contains(..) method will accurately identify which ovals the mouse click falls inside. But the kind of map you are referring to will probably be made of a number of GeneralPath objects (one for each country) that do not overlap.
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.BasicStroke;
import java.awt.RenderingHints;
import java.awt.event.*;
import java.awt.geom.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
import java.io.File;
import java.util.*;
import javax.imageio.ImageIO;
public class ShapeContainment {
List<Ellipse2D> shapes = new ArrayList<Ellipse2D>();
int w = 400;
int h = 100;
BufferedImage img = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Point2D mouse = new Point2D.Double(0, 0);
JLabel l;
ShapeContainment() {
Random r = new Random();
for (int ii = 0; ii < 10; ii++) {
int x = r.nextInt(w / 2);
int y = r.nextInt(h / 2);
int wE = r.nextInt(w - x);
int hE = r.nextInt(h - y);
Ellipse2D ellipse = new Ellipse2D.Double(x, y, wE, hE);
shapes.add(ellipse);
}
l = new JLabel(new ImageIcon(img));
MouseAdapter listener = new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent me) {
mouse = me.getPoint();
drawImage();
}
};
l.addMouseListener(listener);
drawImage();
JOptionPane.showMessageDialog(null, l);
}
public void drawImage() {
Graphics2D g = img.createGraphics();
g.setColor(Color.WHITE);
g.fillRect(0, 0, w, h);
RenderingHints hints = new RenderingHints(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g.setRenderingHints(hints);
Color bg = new Color(0, 128, 0, 60);
Color inside = new Color(0, 0, 255, 120);
Color outside = new Color(255, 0, 0, 120);
g.setStroke(new BasicStroke(4));
for (Ellipse2D shape : shapes) {
g.setColor(bg);
g.fill(shape);
if (shape.contains(mouse)) {
g.setColor(inside);
} else {
g.setColor(outside);
}
g.draw(shape);
}
g.setColor(Color.RED);
int x = (int) mouse.getX();
int y = (int) mouse.getY();
g.setStroke(new BasicStroke(2));
int s = 3;
g.drawLine(x-s, y, x+s, y);
g.drawLine(x, y-s, x, y+s);
l.setIcon(new ImageIcon(img));
g.dispose();
try {
ImageIO.write(
img,
"png",
new File(System.currentTimeMillis() + ".png"));
} catch (Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
Runnable run = new Runnable() {
#Override
public void run() {
new ShapeContainment();
}
};
// Swing GUIs should be created and updated on the EDT
// http://docs.oracle.com/javase/tutorial/uiswing/concurrency/initial.html
SwingUtilities.invokeLater(run);
}
}

How to set a 3D border for a JDialog with rounded corners?

I could add a rounded corner border to my JDialog as in How to create a rounded title border in Java Swing. But it is still one color. I want to make the border looks like 3D.
Here is how I tried.
Graphics2D g2d = (Graphics2D) g;
Color c1 = getBackground();
Color c2 = color1.darker();
int w = getWidth();
int h = getHeight();
GradientPaint gp = new GradientPaint(
0, 0, c1,
0, h, c2);
g2d.setPaint(gp);
g2d.fill3DRect(0,0, w, h,true);
Then, no 3D look, but the border has been widen more with its border color.
How can I achieve this?
Any sample code or links will be highly appreciated.

import java.awt.*;
import java.awt.geom.*;
import javax.swing.*;
import javax.swing.border.*;
public class ThreeDimensionalBorder extends AbstractBorder {
private static final long serialVersionUID = 1L;
private Color color;
private int thickness = 8;
private int radii = 8;
private Insets insets = null;
private BasicStroke stroke = null;
private int strokePad;
RenderingHints hints;
int shadowPad = 3;
ThreeDimensionalBorder(Color color) {
this(color, 128, 8);
}
ThreeDimensionalBorder(Color color, int transparency, int shadowWidth) {
this.color = color;
shadowPad = shadowWidth;
stroke = new BasicStroke(thickness);
strokePad = thickness/2;
hints = new RenderingHints(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
int pad = radii + strokePad;
int bottomPad = pad + strokePad + shadowPad;
int rightPad = pad + strokePad + shadowPad;
insets = new Insets(pad,pad,bottomPad+shadowPad,rightPad);
}
#Override
public Insets getBorderInsets(Component c) {
return insets;
}
#Override
public Insets getBorderInsets(Component c, Insets insets) {
return getBorderInsets(c);
}
#Override
public void paintBorder(
Component c,
Graphics g,
int x, int y,
int width, int height) {
Graphics2D g2 = (Graphics2D)g;
int bottomLineY = height-thickness-shadowPad;
RoundRectangle2D.Double bubble = new RoundRectangle2D.Double(
0+strokePad,
0+strokePad,
width-thickness-shadowPad,
bottomLineY,
radii,
radii
);
Area area = new Area(bubble);
g2.setRenderingHints(hints);
g2.setColor(color);
g2.setStroke(stroke);
g2.draw(area);
Area shadowArea = new Area(new Rectangle(0,0,width,height));
shadowArea.subtract(area);
g.setClip(shadowArea);
Color shadow = new Color(color.getRed(),color.getGreen(),color.getBlue(),128);
g2.setColor(shadow);
g2.translate(shadowPad,shadowPad);
g2.draw(area);
AffineTransform at = g2.getTransform();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JPanel p = new JPanel();
String t = "The quick brown fox jumps over the lazy dog!";
JLabel l1 = new JLabel(t);
l1.setBorder(new ThreeDimensionalBorder(Color.MAGENTA.darker(),128,4));
p.add(l1);
JLabel l2 = new JLabel(t);
l2.setBorder(new ThreeDimensionalBorder(Color.BLACK,200,5));
p.add(l2);
JLabel l3 = new JLabel(t);
l3.setBorder(new ThreeDimensionalBorder(Color.BLUE,40,6));
p.add(l3);
JOptionPane.showMessageDialog(null, p);
}
});
}
}

Would this suffice??
It's far from perfect, but the basic idea works...
public class MyRoundedBorder implements Border {
protected static final Insets DEFAULT_INSETS = new Insets(4, 4, 4, 4);
#Override
public void paintBorder(Component c, Graphics g, int x, int y, int width, int height) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.setStroke(new BasicStroke(3, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
g2d.setColor(Color.WHITE);
Shape corner = new RoundedShape(width - 8, height - 8);
g2d.translate(x + 2, y + 2);
g2d.draw(corner);
g2d.transform(AffineTransform.getRotateInstance(Math.toRadians(180), (width - 8) / 2, (height - 8) / 2));
g2d.setColor(Color.LIGHT_GRAY);
g2d.draw(corner);
g2d.dispose();
}
#Override
public Insets getBorderInsets(Component c) {
return DEFAULT_INSETS;
}
#Override
public boolean isBorderOpaque() {
return true;
}
public class RoundedShape extends Path2D.Float {
public RoundedShape(int width, int height) {
moveTo(0, height - 20);
append(new Arc2D.Float(0, height - 20, 20, 20, 180, 45, Arc2D.CHORD), false);
lineTo(0, 20);
curveTo(0, 0, 0, 0, 20, 0);
lineTo(width - 10, 0);
append(new Arc2D.Float(width - 20, 0, 20, 20, 90, -45, Arc2D.CHORD), false);
}
}
}