Java Paint Method Doesn't Paint? - java

I'm working on a simple little swing component, and I'm tearing out my hair trying to figure out why my paint method isn't working.
The idea behind this component is that it's a small JPanel with a label. The background (behind the label) is supposed to be white, with a colored rectangle on the left-hand side indicating the ratio of two measurements: "actual" and "expected".
If you had a bunch of these components aligned vertically, they'd form a bar chart, composed of horizontal bars.
This kind of thing should be super-simple.
Anyhow, here's the code:
package com.mycompany.view;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Rectangle;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class BarGraphPanel extends JPanel {
private static final Color BACKGROUND = Color.WHITE;
private static final Color FOREGROUND = Color.BLACK;
private static final Color BORDER_COLOR = new Color(229, 172, 0);
private static final Color BAR_GRAPH_COLOR = new Color(255, 255, 165);
private int actual = 0;
private int expected = 1;
private JLabel label;
public BarGraphPanel() {
super();
label = new JLabel();
label.setOpaque(false);
label.setForeground(FOREGROUND);
super.add(label);
super.setOpaque(true);
}
public void setActualAndExpected(int actual, int expected) {
this.actual = actual;
this.expected = expected;
}
#Override
public void paint(Graphics g) {
double proportion = (expected == 0) ? 0 : ((double) actual) / expected;
Rectangle bounds = super.getBounds();
g.setColor(BACKGROUND);
g.fillRect(bounds.x, bounds.y, bounds.width, bounds.height);
g.setColor(BAR_GRAPH_COLOR);
g.fillRect(bounds.x, bounds.y, (int) (bounds.width * proportion), bounds.height);
g.setColor(BORDER_COLOR);
g.drawRect(bounds.x, bounds.y, bounds.width, bounds.height);
label.setText(String.format("%s of %s (%.1f%%)", actual, expected, proportion * 100));
super.paint(g);
g.dispose();
}
}
And here's the simple test harness:
package com.mycompany.view;
import java.awt.Dimension;
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.UIManager;
public class MyFrame extends JFrame {
public MyFrame() {
super();
super.setLayout(new GridLayout(3, 1));
super.setPreferredSize(new Dimension(300, 200));
BarGraphPanel a = new BarGraphPanel();
BarGraphPanel b = new BarGraphPanel();
BarGraphPanel c = new BarGraphPanel();
a.setActualAndExpected(75, 100);
b.setActualAndExpected(85, 200);
c.setActualAndExpected(20, 300);
super.add(a);
super.add(b);
super.add(c);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
public static void createAndShowGUI() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Throwable t) { }
MyFrame frame = new MyFrame();
frame.pack();
frame.setVisible(true);
}
}
The test harness creates a simple frame and then adds three of these controls.
The labels are all rendered correctly, which indicates to me that the paint() method is actually being called, but the rectangles aren't being drawn to the Graphics object.
What am I doing wrong?
And why does Swing programming suck so much?
Here's my final code. Thanks, everyone, for your help!
public void paintComponent(Graphics g) {
double proportion = (expected == 0) ? 0 : ((double) actual) / expected;
Rectangle bounds = super.getBounds();
g.setColor(BACKGROUND);
g.fillRect(0, 0, bounds.width, bounds.height);
g.setColor(BAR_GRAPH_COLOR);
g.fillRect(0, 0, (int) (bounds.width * proportion), bounds.height);
g.setColor(BORDER_COLOR);
g.drawRect(0, 0, bounds.width - 1, bounds.height - 1);
FontMetrics metrics = g.getFontMetrics();
String label = String.format("%s of %s (%.1f%%)", actual, expected, proportion * 100);
Rectangle2D textBounds = metrics.getStringBounds(label, g);
g.setColor(FOREGROUND);
g.drawString(label, 5, (int) ((bounds.height + textBounds.getHeight()) / 2));
}

I think you've almost answered your own question in the comments, along with David's answer. Change paint(Graphics g) to paintComponent(Graphics g) and remove the last two lines of the method, and you should be fine.
EDIT: Oddly, this only works for the first bar of the three. More testing in progress...
By the way, you have an off-by-one error in the border-painting code. It should be:
g.setColor(BORDER_COLOR);
g.drawRect(bounds.x, bounds.y, bounds.width - 1, bounds.height - 1);
EDIT2: OK, got it. Your full paintComponent method should be as follows:
#Override
public void paintComponent(Graphics g) {
double proportion = (expected == 0) ? 0 : ((double) actual) / expected;
Rectangle bounds = super.getBounds();
g.setColor(BACKGROUND);
g.fillRect(0, 0, bounds.width, bounds.height);
g.setColor(BAR_GRAPH_COLOR);
g.fillRect(0, 0, (int) (bounds.width * proportion), bounds.height);
g.setColor(BORDER_COLOR);
g.drawRect(0, 0, bounds.width-1, bounds.height-1);
label.setText(String.format("%s of %s (%.1f%%)", actual, expected, proportion * 100));
}
Note that the coordinates given to g.fillRect() and g.drawRect() are relative to the component, so they must start at (0,0).
And no, I can't help you with your last question, though I feel your pain. :)

In your JPanel, you called super.setOpaque(true). The JPanel is going to completely fill in the background when you call super.paint() and overwrite your retangles.

Not sure if this is the source of your problem, but in Swing you're supposed to override paintComponent(Graphics2D) instead...

If anything, I think you should be calling super.paint(g); at the TOP of your method, not at the very bottom. It's possible the superclass is drawing on top of your stuff.

Related

Rotating a graphic using arc2d

i am trying to do a roulette casino game, so for this i made my roulette using the Arc2D package.
My code below
package roulette;
import javax.swing.*;
import java.awt.*;
import java.awt.geom.Arc2D;
import java.awt.geom.AffineTransform;
import javax.swing.Timer;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class RouletteInterface extends JPanel{
public int spinValue = 0;
public void paint(Graphics g){
Graphics2D g2d = (Graphics2D)g;
paintRoulette(g2d);
}
public void paintRoulette(Graphics2D g2d) {
RenderingHints hints = new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setRenderingHints(hints);
AffineTransform at = AffineTransform.getTranslateInstance(10, 10);
at.rotate(spinValue, 10, 10);
double angle = 360 / 36.9;
double startAngle = 0;
int color = 0;
for(int i = 0; i < 37; i++) {
if(i == 0) {
g2d.setColor(Color.GREEN);
} else {
if(color == 0) {
g2d.setColor(Color.BLACK);
color = 1;
} else {
g2d.setColor(Color.RED);
color = 0;
}
}
g2d.fill(new Arc2D.Double(100, 100, 300, 300, startAngle, angle, Arc2D.PIE));
startAngle += angle;
}
g2d.transform(at);
Timer timer = new Timer(5, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
spinValue += 0.01;
repaint();
}
});
timer.start();
}
}
In short i am not using a generalpath because i want to fill each arc with color red/green or black like the original roulette, and for the rotation i tried using a timer to increase the spinValue (this worked for me but when i use a generalpath) for the AfinneTransformation, but when i run the code, well, nothing happens. It shows me only the roulette without animation. What can i do?
Thanks in advance.
Painting and graphics in general are quite advanced topics, Java/Swing does a good job to "commonalise" the APIs into something which is reasonable easy to use, but still takes time and effort to learn and understand fully.
I would highly recommend having Performing Custom Painting, Painting in AWT and Swing and 2D Graphics and the JavaDocs booked marked, as you will be coming back to them on a regular bases (I still do)
There are lots of issues, which are compounding to make your life difficult.
Starting with...
public void paint(Graphics g){
Graphics2D g2d = (Graphics2D)g;
paintRoulette(g2d);
}
You should favour overriding paintComponent instead of paint, paint is a complicated process and you need to choose your entry point into carefully. Also, you should always call the paint methods super method, unless you are absolutely, positively prepared to take over its core functionality yourself.
In your case, you should also be making a copy of the Graphics context before passing it to paintRoulette, as Graphics is a shared resource and the transformations you are applying will cause issues for anything which is painted after your component.
Transformations...
AffineTransform at = AffineTransform.getTranslateInstance(10, 10);
at.rotate(spinValue, 10, 10);
This is somewhat interesting. You're creating translation of 10x10 which will move the origin point of the Graphics context. You then apply a rotation, which is anchored to 10x10.
The reason I mention it is because you then do...
g2d.fill(new Arc2D.Double(100, 100, 300, 300, startAngle, angle, Arc2D.PIE));
This means that the arc is offset by 110x110 from the corner of the component (add in your translation) and you'll be rotating about a point 20x20 from the component's top/left corner (add in your translation) ... this is weird to me because the centre of the of wheel is actually at 250x250 (from the component's top/left corner) which is going to make for one very weird affect.
Finally, you apply the transformation AFTER the painting is done AND then create a Timer inside the paint method...
Painting is done in serial. So one operation will effect the next, this will mean you will need to apply the transformation BEFORE you paint something (that you want transformed)
You also need to understand that you don't control the paint process, this means that your component may be painted for any number of reason at any time without your interaction. This means you could an infinite number of Timers, over a very small period of time.
Instead, your timer should be controlled externally from the paint process.
One other thing that took me some time to work out is...
public int spinValue = 0;
//...
Timer timer = new Timer(5, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
spinValue += 0.01;
repaint();
}
});
You declare spinValue as int, but are adding a floating point value to it, this will have the effect of the decimal component been truncated, so the value will ALWAYS be 0.
Also, AffineTransform#rotate expects angles to be in radians, not degrees. Not sure if it's important, but you should be aware of it.
Runnable example...
Okay, so after applying the above, the code "might" look something like...
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.AffineTransform;
import java.awt.geom.Arc2D;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new RoulettePane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class RoulettePane extends JPanel {
private double spinValue = 0;
private Timer timer;
public RoulettePane() {
addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
spin();
}
});
}
#Override
public Dimension getPreferredSize() {
return new Dimension(300, 300);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
paintRoulette(g2d);
g2d.dispose();
}
protected void spin() {
if (timer != null && timer.isRunning()) {
return;
}
timer = new Timer(5, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
spinValue += 0.01;
repaint();
}
});
timer.start();
}
protected void paintRoulette(Graphics2D g2d) {
RenderingHints hints = new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setRenderingHints(hints);
int width = getWidth();
int height = getHeight();
int dimeter = Math.min(width, height);
AffineTransform at = AffineTransform.getRotateInstance(spinValue, dimeter / 2, dimeter / 2);
g2d.transform(at);
double angle = 360 / 36.9;
double startAngle = 0;
int color = 0;
for (int i = 0; i < 37; i++) {
if (i == 0) {
g2d.setColor(Color.GREEN);
} else {
if (color == 0) {
g2d.setColor(Color.BLACK);
color = 1;
} else {
g2d.setColor(Color.RED);
color = 0;
}
}
g2d.fill(new Arc2D.Double(0, 0, dimeter, dimeter, startAngle, angle, Arc2D.PIE));
startAngle += angle;
}
}
}
}
nb: I took the translation out for the time been as I wanted to focus on making the output more dynamic based on the actual width/height of the component

java graphics variables giving wrong value

Hello I wonder if anyone can help me , I have declared 2 values x1, y1 both as 120 and trying to use these in the following method:
private void drawDot(int x, int y, Graphics2D twoD) {
twoD.fillOval(x-50, y-50, 100, 100);
}
However when I use drawDot(120,120,twoD) it paints the filled oval in the wrong place compared to when I manually use
twoD.fillOval(70,70,100,100);
Shouldn't these 2 statements do the exact same thing? Is there something I am missing? I have added an image to show the issue, the oval on the left is the oval drawn by my drawDot method and the oval on the right is the oval in the correct place as it should be. If anyone has any advice it would be greatly appreciated. Thanks
click this link to see how both ovals are drawn
the entire class:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class DieFace extends JPanel {
int x1,y1 = 120;
int x2,y2 = 300;
int x3,y3 = 480;
private BufferedImage bufferedImage;
public DieFace() {
this.init();
this.frameInit();
updateVal(1);
}
private void init() {
this.setPreferredSize(new Dimension(600,600));
}
private void frameInit() {
JFrame window = new JFrame("Dice Simulation");
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setContentPane(this);
window.pack();
window.setVisible(true);
window.setLocationRelativeTo(null);
}
public void paintComponent(Graphics g) {
Graphics2D twoD = (Graphics2D) g;
twoD.drawImage(bufferedImage,0,0,null);
}
private void drawDot(int x, int y, Graphics2D twoD) {
twoD.fillOval(x-50, y-50, 100, 100);
}
public void updateVal(int dieRoll) {
bufferedImage = new BufferedImage(600,600,BufferedImage.TYPE_INT_ARGB);
Graphics2D twoD = bufferedImage.createGraphics();
twoD.setColor(Color.WHITE);
twoD.fillRect(0, 0, 600, 600);
twoD.setColor(Color.BLACK);
if(dieRoll==1) {
drawDot(x1,y1,twoD);
twoD.fillOval(70, 70, 100, 100);
}
repaint();
}
}
Shouldn't these 2 statements do the exact same thing? Is there something I am missing?
Because you made a mistake in your variable initializations on x1, y1:
int x1,y1 = 120; //This means x1 = 0, y1 = 120
What you actually wanted is:
int x1 = 120, y1 = 120;
Since x1 is not 120, when you invoke
drawDot(x1,y1,twoD);
drawDot(0, 120, twoD); is being invoked
Hence both elipses will appear on the same y-axis, but different on the x-axis.

Rescale a drawing in Java (JFrame)

I need the simplest way to rescale a drawing in java (for example a rectangle...). I found a way to "stretch" them:
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JFrame;
import java.awt.Dimension;
public class Stretch extends JFrame {
int originalHeight = 600;
int originalWidth = 600;
public Stretch() {
super("Stretch");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(originalWidth, originalHeight);
}
public static void main(String[] args) {
Stretch s = new Stretch();
s.setVisible(true);
}
public void paint(Graphics g) {
Dimension size = this.getBounds().getSize();
int rectWidth = 100;
int rectHeight = 130;
g.setColor(Color.white);
g.fillRect(0, 0, size.width, size.height);
g.setColor(Color.black);
g.drawRect(100, 100, rectWidth + size.width - originalWidth, rectHeight + size.height - originalHeight);
}
}
As you can see the formula is like that:
g.drawRect(100, 100, rectWidth + size.width - originalWidth, rectHeight + size.height - originalHeight);
Now how can I rescale the drawing? Width and height have to maintain the same proportion.
Thank you.
There are bascially two different approaches for this:
You can "scale the whole Graphics"
You can scale the actual shapes
The difference may be subtle in some cases, but can be important: When you scale the whole Graphics, then everything will be scaled. Particularly, when you scale it about 2.0, and then draw a line with a width of 1.0, the line will be drawn 2 pixels wide. Whether or not this is desired depends on the application case.
In order to scale the actual shapes, you can not use the drawRect method. Instead you will have to create Shape instances that represent the geometric shapes. You can then create scaled versions of these shapes with AffineTransform#createTransformedShape.
Here is an example that compares both approaches (and corrects some of the other issues that have been in your code). In both cases, the same rectangle with an original size of (10,13) is painted, scaled by a factor of 5.0.
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Shape;
import java.awt.geom.AffineTransform;
import java.awt.geom.Rectangle2D;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class ScalingDrawnObjects
{
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
#Override
public void run()
{
createAndShowGUI();
}
});
}
private static void createAndShowGUI()
{
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ScalingDrawnObjectsPanel p = new ScalingDrawnObjectsPanel();
f.getContentPane().add(p);
f.setSize(600,400);
f.setLocationRelativeTo(null);
f.setVisible(true);
}
}
class ScalingDrawnObjectsPanel extends JPanel
{
#Override
protected void paintComponent(Graphics gr)
{
super.paintComponent(gr);
Graphics2D g = (Graphics2D)gr;
Shape rectangle = new Rectangle2D.Double(2, 2, 10, 13);
g.setColor(Color.RED);
drawWithScaledGraphics(g, rectangle);
g.translate(100, 0);
drawScaledObject(g, rectangle);
}
private static void drawWithScaledGraphics(Graphics2D g, Shape shape)
{
AffineTransform oldAt = g.getTransform();
g.scale(5.0, 5.0);
g.draw(shape);
g.setTransform(oldAt);
}
private static void drawScaledObject(Graphics2D g, Shape shape)
{
AffineTransform at = AffineTransform.getScaleInstance(5.0, 5.0);
g.draw(at.createTransformedShape(shape));
}
}
EDIT In response to the comment
The code that I posted is not "complicated". It is as compilcated as it has to be, but not more. You should not extend JFrame and you should not override paint. You should create the GUI on the EDT. You should ...
However, you should not use code like the following, but maybe this is what you're looking for
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JFrame;
import java.awt.Dimension;
public class Stretch extends JFrame {
int originalHeight = 600;
int originalWidth = 600;
public Stretch() {
super("Stretch");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(originalWidth, originalHeight);
}
public static void main(String[] args) {
Stretch s = new Stretch();
s.setVisible(true);
}
public void paint(Graphics g) {
Dimension size = this.getBounds().getSize();
int rectWidth = 100;
int rectHeight = 130;
g.setColor(Color.white);
g.fillRect(0, 0, size.width, size.height);
g.setColor(Color.black);
int w = rectWidth + size.width - originalWidth;
int h = rectHeight + size.height - originalHeight;
double sx = (double)w / rectWidth;
double sy = (double)h / rectHeight;
double s = Math.min(sx, sy);
int fw = (int)(s * rectWidth);
int fh = (int)(s * rectHeight);
g.drawRect(100, 100, fw, fh);
}
}
How about multiplying the width and the height by the scale you want?
So if you want to scale it by 2:
g.drawRect(100, 100, 2 * (rectWidth + size.width - originalWidth), 2 * (rectHeight + size.height - originalHeight));

rotate an Ellipse2D object

I'm trying to rotate one whole Ellipse2D object based on user key input. If the user presses the right key, rotate right and left key means rotate left. The rotAngle is set to 25. I made a separate drawRotEllipse because otherwise it would have always drawn the original one. I think my confusion is happening with the Graphics and Shapes Objects. Tried the AffineTransform business but that didn't work out either. I just want it to rotate about the center. Thanks for any help!
class Canvas extends JPanel implements java.io.Serializable{
int x1 = (int) (this.getWidth()/2)+100;
int y1 = (int) (this.getHeight()/2)+20;
int x2 = (int) this.getWidth()+100;
int y2 = (int) this.getHeight()+200;
#Override
public void paintComponent(Graphics g){
g.setColor(Color.WHITE);
g.fillRect(0, 0, this.getWidth(), this.getHeight());
g.setColor(Color.RED);
drawEllipse(g);
}
public void drawEllipse (Graphics g){
Graphics2D g2d = (Graphics2D) g;
myShape = new Ellipse2D.Double(x1,y1,x2,y2);
g2d.draw(myShape);
this.repaint();
}
public void drawRotEllipse (Graphics g){
g2d.draw(myShape);
this.repaint();
}
}
private void jPanel1KeyPressed(java.awt.event.KeyEvent evt) {
if (evt.getKeyCode()==39){
g2d.rotate(Math.toDegrees(rotAngle));
myCanvas.drawRotEllipse(g2d);
}
else if (evt.getKeyCode()==37){
g2d.rotate(Math.toDegrees(-rotAngle));
myCanvas.drawRotEllipse(g2d);
}
}
if (evt.getKeyCode()==39)
Don't use magic numbers. People don't know that means by just looking at the code.
Instead use variable provided by the API:
if (evt.getKeyCode() == KeyEvent.VK_RIGHT)
You KeyEvent code should not do the actual painting. All the code should do is set the "degrees" property of your class. The setDegrees(...) method will then be responsible for invoking repaint(). Now whenever the component is repainted the shape will be painted at its current degrees of rotation.
Here is an example that uses a JSlider to change the rotation degrees of the class.
It rotates an image. You should be able to change the code rotation the image to just draw your shape:
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;
import javax.swing.event.*;
public class Rotation2 extends JPanel
{
BufferedImage image;
int degrees;
int point = 250;
public Rotation2(BufferedImage image)
{
this.image = image;
setDegrees( 0 );
setPreferredSize( new Dimension(600, 600) );
}
#Override
protected void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g.create();
double radians = Math.toRadians( degrees );
g2.translate(point, point);
g2.rotate(radians);
g2.translate(-image.getWidth(this) / 2, -image.getHeight(this) / 2);
g2.drawImage(image, 0, 0, null);
g2.dispose();
g.setColor(Color.RED);
g.fillOval(point - 5, point - 5, 10, 10);
}
public void setDegrees(int degrees)
{
this.degrees = degrees;
repaint();
}
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
try
{
// String path = "mong.jpg";
String path = "dukewavered.gif";
ClassLoader cl = Rotation2.class.getClassLoader();
BufferedImage bi = ImageIO.read(cl.getResourceAsStream(path));
final Rotation2 r = new Rotation2(bi);
final JSlider slider = new JSlider(JSlider.HORIZONTAL, 0, 360, 0);
slider.addChangeListener(new ChangeListener()
{
public void stateChanged(ChangeEvent e)
{
int value = slider.getValue();
r.setDegrees( value );
}
});
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(new JScrollPane(r));
f.add(slider, BorderLayout.SOUTH);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
catch(IOException e)
{
System.out.println(e);
}
}
});
}
}

Change the JSlider look and feel

I have gone through this website Change look and feel of JSlider
but except for Slider.altTrackColor nothing else is working. I want to do something like shown in pic1 any suggestion would be of great help. I'm working on JDK 1.6.
UIDefaults defaults = UIManager.getDefaults();
defaults.put("Slider.altTrackColor", Color.red);
defaults.put("Slider.thumb", Color.red);
I have also tried this:
WindowUtilities.setNativeLookAndFeel();
// WindowUtilities.setNimbuzzLookAndFeel();
// WindowUtilities.setJavaLookAndFeel();
WindowUtilities is class that tells the system to use native look and feel, as in previous releases. Metal (Java) LAF is the default otherwise.
public static void setNativeLookAndFeel() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch(Exception e) {
System.out.println("Error setting native LAF: " + e);
}
Here is a full example of working UI that shown on 1st image:
(no magic - just a bit of work with graphics and basic UI knowledge)
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.Stroke;
import java.awt.geom.GeneralPath;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JSlider;
import javax.swing.SwingConstants;
import javax.swing.plaf.basic.BasicSliderUI;
/**
*
* #see http://stackoverflow.com/a/12297384/714968
*/
public class CustomSliderUI extends BasicSliderUI {
private BasicStroke stroke = new BasicStroke(1f, BasicStroke.CAP_ROUND,
BasicStroke.JOIN_ROUND, 0f, new float[]{1f, 2f}, 0f);
public CustomSliderUI(JSlider b) {
super(b);
}
#Override
public void paint(Graphics g, JComponent c) {
Graphics2D g2d = (Graphics2D) g;
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
super.paint(g, c);
}
#Override
protected Dimension getThumbSize() {
return new Dimension(12, 16);
}
#Override
public void paintTrack(Graphics g) {
Graphics2D g2d = (Graphics2D) g;
Stroke old = g2d.getStroke();
g2d.setStroke(stroke);
g2d.setPaint(Color.BLACK);
if (slider.getOrientation() == SwingConstants.HORIZONTAL) {
g2d.drawLine(trackRect.x, trackRect.y + trackRect.height / 2,
trackRect.x + trackRect.width, trackRect.y + trackRect.height / 2);
} else {
g2d.drawLine(trackRect.x + trackRect.width / 2, trackRect.y,
trackRect.x + trackRect.width / 2, trackRect.y + trackRect.height);
}
g2d.setStroke(old);
}
#Override
public void paintThumb(Graphics g) {
Graphics2D g2d = (Graphics2D) g;
int x1 = thumbRect.x + 2;
int x2 = thumbRect.x + thumbRect.width - 2;
int width = thumbRect.width - 4;
int topY = thumbRect.y + thumbRect.height / 2 - thumbRect.width / 3;
GeneralPath shape = new GeneralPath(GeneralPath.WIND_EVEN_ODD);
shape.moveTo(x1, topY);
shape.lineTo(x2, topY);
shape.lineTo((x1 + x2) / 2, topY + width);
shape.closePath();
g2d.setPaint(new Color(81, 83, 186));
g2d.fill(shape);
Stroke old = g2d.getStroke();
g2d.setStroke(new BasicStroke(2f));
g2d.setPaint(new Color(131, 127, 211));
g2d.draw(shape);
g2d.setStroke(old);
}
public static void main(String[] args) {
JFrame frame = new JFrame();
JSlider slider = new JSlider(0, 100);
slider.setPaintTicks(true);
slider.setPaintLabels(true);
slider.setMinorTickSpacing(5);
slider.setMajorTickSpacing(25);
slider.setUI(new CustomSliderUI(slider));
frame.add(slider);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
}
You can easily modify the thumb (gripper) size by changing the returned bounds. The thumb painting will adapt to any size. And you can also easily customize painting of any other slider part.
Here is the final view by the way:
P.S. I did not adapt UI for vertical sliders, but that shouldn't take too long.

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