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Weird issue updating a JLabel on JSlider change

Huy guys, I have a weird problem.
I'm kinda new to swing and java applications.
I'm trying to make a custom UI jslider that changes a jlabel text when you move the thumb.
My problem is: when I use the addChangeListener(), it creates a weird glitch when moving the thumb.
If I don't use it, it works perfectly fine.
How can I update the JLabel without using the change listener or how can I fix this graphic bug?
Most of this code comes from stackoverflow since I don't know much about painting components.
See pictures at the button to better understand the problem
Thanks!
The code in my jpanel
JSlider slider = new JSlider(SwingConstants.HORIZONTAL, 1, 10, 1) {
#Override
public void updateUI() {
setUI(new CustomSliderUI(this));
}
};
// If I comment this line the visual glitch is gone when moving the thumb, but the value doesnt update
slider.addChangeListener((event) -> RAM_LABEL.setText(slider.getValue() + " Gb"));
slider.setMinorTickSpacing(1);
slider.setMajorTickSpacing(10);
slider.setSnapToTicks(true);
slider.setBounds(96, 317, 300, 35);
slider.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
slider.setOpaque(false);
this.add(slider);
The custom slider ui class
private static class CustomSliderUI extends BasicSliderUI
{
private static final int TRACK_HEIGHT = 8;
private static final int TRACK_ARC = 5;
private static final Dimension THUMB_SIZE = new Dimension(22, 20);
private final RoundRectangle2D.Float trackShape = new RoundRectangle2D.Float();
private final Image knob;
public CustomSliderUI(final JSlider b)
{
super(b);
knob = Swinger.getResource("knob.png");
}
#Override
protected void calculateTrackRect() {
super.calculateTrackRect();
trackRect.y = trackRect.y + (trackRect.height - TRACK_HEIGHT) / 2;
trackRect.height = TRACK_HEIGHT;
trackShape.setRoundRect(trackRect.x, trackRect.y, trackRect.width, trackRect.height, TRACK_ARC, TRACK_ARC);
}
#Override
protected void calculateThumbLocation() {
super.calculateThumbLocation();
thumbRect.y = trackRect.y + (trackRect.height - thumbRect.height) / 2;
}
#Override
protected Dimension getThumbSize() {
return THUMB_SIZE;
}
#Override
public void paint(final Graphics g, final JComponent c) {
((Graphics2D) g).setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
super.paint(g, c);
}
#Override
public void paintTrack(final Graphics g) {
Graphics2D g2 = (Graphics2D) g;
Shape clip = g2.getClip();
boolean inverted = slider.getInverted();
// Paint shadow.
g2.setColor(new Color(170, 170 ,170));
g2.fill(trackShape);
// Paint track background.
g2.setColor(new Color(200, 200 ,200));
g2.setClip(trackShape);
trackShape.y += 1;
g2.fill(trackShape);
trackShape.y = trackRect.y;
g2.setClip(clip);
// Paint selected track.
boolean ltr = slider.getComponentOrientation().isLeftToRight();
if (ltr) inverted = !inverted;
int thumbPos = thumbRect.x + thumbRect.width / 2;
if (inverted) {
g2.clipRect(0, 0, thumbPos, slider.getHeight());
} else {
g2.clipRect(thumbPos, 0, slider.getWidth() - thumbPos, slider.getHeight());
}
g2.setColor(Swinger.getTransparentWhite(0));
g2.fill(trackShape);
g2.setClip(clip);
}
#Override
public void paintThumb(final Graphics g)
{
g.drawImage(knob, thumbRect.x, thumbRect.y, null);
}
#Override
public void paintFocus(final Graphics g) {}
}
Visual glitch when you are moving the cursor, as soon as you stop pressing the mouse it goes back to normal
Regular cursor / when I move it without the change listener

Solved. I went with drawing my own background it was simplier.
private static class CustomSliderUI extends BasicSliderUI
{
private static final Dimension THUMB_SIZE = new Dimension(22, 20);
private final Image thumb, background;
private final JSlider slider;
public CustomSliderUI(final JSlider b)
{
super(b);
slider = b;
thumb = Swinger.getResource("thumb.png");
background = Swinger.getResource("slider.png");
}
#Override
protected Dimension getThumbSize() {
return THUMB_SIZE;
}
#Override
public void paintTrack(final Graphics g) {
g.drawImage(background, 10, 11, 280, 10, null);
}
#Override
public void paintThumb(final Graphics g)
{
g.drawImage(thumb, thumbRect.x, thumbRect.y, null);
slider.repaint();
}
#Override
public void paintFocus(final Graphics g) {}
}
JSlider slider = new JSlider(SwingConstants.HORIZONTAL, 1, 10, 1) {
#Override
public void updateUI() {
setUI(new CustomSliderUI(this));
}
};
slider.addChangeListener((event) -> RAM_LABEL.setText(slider.getValue() + " Gb"));
slider.setBounds(96, 317, 300, 35);
slider.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
slider.setOpaque(false);
this.add(slider);

java- repaint() method is misbehaving?

I am working on a Music Player
I am using a JSlider as seek bar and using a JLabel to draw text on screen, such as song name.
I am new to Graphics2D
Here's the minimized code:
public class JSliderDemo extends JFrame
{
JLabel label;
JSlider seek = new JSlider();
int y = 10;
public JSliderDemo()
{
setSize(400, 400);
setLocationRelativeTo(null);
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
createWindow();
setVisible(true);
startThread();
}
public void createWindow()
{
JPanel panel = new JPanel(null);
panel.setOpaque(true);
panel.setBackground(Color.BLUE);
label = new Component();
label.setSize(400, 400);
label.setLocation(0, 0);
createSlider();
panel.add(seek);
panel.add(label);
add(panel);
}
protected void createSlider()
{
seek.setUI(new SeekBar(seek, 300, 10, new Dimension(20, 20), 5,
Color.DARK_GRAY, Color.RED, Color.RED));
seek.setOrientation(JProgressBar.HORIZONTAL);
seek.setOpaque(false);
seek.setLocation(10, 50);
seek.setSize(300, 20);
seek.setMajorTickSpacing(0);
seek.setMinorTickSpacing(0);
seek.setMinimum(0);
seek.setMaximum(1000);
}
protected void startThread()
{
Thread thread = new Thread(new Runnable(){
#Override
public void run()
{
try
{
while(true)
{
if(y == label.getHeight()){y = 1;}
label.repaint();
y += 1;
Thread.sleep(100);
}
}
catch(Exception ex){}
}
});
thread.start();
}
protected class Component extends JLabel
{
#Override
public void paintComponent(Graphics g)
{
Graphics2D gr = (Graphics2D) g;
gr.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
gr.setColor(Color.RED);
gr.setFont(new Font("Calibri", Font.PLAIN, 16));
gr.drawString("Slider", 50, y);
}
}
public static void main(String[] args)
{
new JSliderDemo();
}
}
The Custom Slider UI class prints a line each time the JSlider is repainted.
Through this, I was able to find out that, when I call repaint() for JLabel it automatically repaints JSlider with it even though JSlider is not included in JLabel.
Output :
Slider re-painted
Slider re-painted
Slider re-painted
Slider re-painted
Slider re-painted
Slider re-painted.........
Now if I remove label.repaint() from the Thread, then the JSlider is not re-painted.
Output:
Slider re-painted
Slider re-painted
Is the repaint() method supposed to work like this?
Here's the Custom Slider UI class :
package jsliderdemo;
import java.awt.*;
import javax.swing.*;
import java.awt.geom.RoundRectangle2D;
import javax.swing.plaf.basic.BasicSliderUI;
public class SeekBar extends BasicSliderUI
{
private int TRACK_ARC = 5;
private int TRACK_WIDTH = 8;
private int TRACK_HEIGHT = 8;
private Color backGround = Color.GRAY;
private Color trackColor = Color.RED;
private Color thumbColor = Color.WHITE;
private Dimension THUMB_SIZE = new Dimension(20, 20);
private final RoundRectangle2D.Float trackShape = new RoundRectangle2D.Float();
public SeekBar(final JSlider b, int width, int height, Dimension thumbSize, int arc,
Color backGround, Color trackColor, Color thumbColor)
{
super(b);
this.TRACK_ARC = arc;
this.TRACK_WIDTH = width;
this.TRACK_HEIGHT = height;
this.THUMB_SIZE = thumbSize;
this.backGround = backGround;
this.trackColor = trackColor;
this.thumbColor = thumbColor;
}
#Override
protected void calculateTrackRect()
{
super.calculateTrackRect();
if (isHorizontal())
{
trackRect.y = trackRect.y + (trackRect.height - TRACK_HEIGHT) / 2;
trackRect.height = TRACK_HEIGHT;
}
else
{
trackRect.x = trackRect.x + (trackRect.width - TRACK_WIDTH) / 2;
trackRect.width = TRACK_WIDTH;
}
trackShape.setRoundRect(trackRect.x, trackRect.y, trackRect.width, trackRect.height, TRACK_ARC, TRACK_ARC);
}
#Override
protected void calculateThumbLocation()
{
super.calculateThumbLocation();
if (isHorizontal())
{
thumbRect.y = trackRect.y + (trackRect.height - thumbRect.height) / 2;
}
else
{
thumbRect.x = trackRect.x + (trackRect.width - thumbRect.width) / 2;
}
}
#Override
protected Dimension getThumbSize()
{
return THUMB_SIZE;
}
private boolean isHorizontal()
{
return slider.getOrientation() == JSlider.HORIZONTAL;
}
#Override
public void paint(final Graphics g, final JComponent c)
{
((Graphics2D) g).setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
super.paint(g, c);
}
#Override
public void paintTrack(final Graphics g)
{
System.out.println("Slider re-painted");
Graphics2D g2 = (Graphics2D) g;
Shape clip = g2.getClip();
boolean horizontal = isHorizontal();
boolean inverted = slider.getInverted();
// Paint shadow.
//g2.setColor(new Color(170, 170 ,170));
//g2.fill(trackShape);
// Paint track background.
g2.setColor(backGround);
g2.setClip(trackShape);
trackShape.y += 1;
g2.fill(trackShape);
trackShape.y = trackRect.y;
g2.setClip(clip);
// Paint selected track.
if (horizontal)
{
boolean ltr = slider.getComponentOrientation().isLeftToRight();
if (ltr) inverted = !inverted;
int thumbPos = thumbRect.x + thumbRect.width / 2;
if (inverted)
{
g2.clipRect(0, 0, thumbPos, slider.getHeight());
}
else
{
g2.clipRect(thumbPos, 0, slider.getWidth() - thumbPos, slider.getHeight());
}
}
else
{
int thumbPos = thumbRect.y + thumbRect.height / 2;
if (inverted)
{
g2.clipRect(0, 0, slider.getHeight(), thumbPos);
}
else
{
g2.clipRect(0, thumbPos, slider.getWidth(), slider.getHeight() - thumbPos);
}
}
g2.setColor(trackColor);
g2.fill(trackShape);
g2.setClip(clip);
}
#Override
public void paintThumb(final Graphics g)
{
g.setColor(thumbColor);
g.fillOval(thumbRect.x, thumbRect.y, thumbRect.width, thumbRect.height);
}
#Override
public void paintFocus(final Graphics g) {}
}

Java - JComponent in polygon shape with background image

I want to have a JComponent on my JFrame, that has a custom shape in form of a polygon. Now i want to add a background image with colors in the same shape and blank color in the rest.
Is there a way to achieve this?
I have this test class:
public class Test extends JButton {
private final Polygon shape;
private final int provinceId;
private ImageIcon img;
public Test(Polygon p, int x, int y, int w, int h, int id, ImageIcon img) {
this.shape = p;
this.provinceId = id;
this.img = img;
setSize(w, h);
setLocation(x, y);
setIcon(img);
setContentAreaFilled(false);
addMouseListener(animation());
}
private MouseListener animation() {
return new MouseListener() {
public void mouseEntered(MouseEvent e) {
System.out.println("in");
}
public void mouseExited(MouseEvent e) {
System.out.println("out");
}
public void mouseClicked(MouseEvent e) {
}
public void mousePressed(MouseEvent e) {
}
public void mouseReleased(MouseEvent e) {
}
};
}
protected void paintComponent(Graphics g) {
g.drawPolygon(this.shape);
}
protected void paintBorder(Graphics g) {
g.drawPolygon(this.shape);
}
public boolean contains(int x, int y) {
return this.shape.contains(x, y);
}
public boolean isOpaque() {
return false;
}
public int getId() {
return this.provinceId;
}
public static void main(String[] args) {
JFrame f = new JFrame();
//Polygon p = new Polygon(new int[] {0, 400, 400, 0}, new int[] {0, 0, 300, 300}, 4);
Polygon p = new Polygon(new int[] {50, 150, 250, 350, 200, 50}, new int[] {0, 0, 50, 200, 300, 200}, 6);
ImageIcon ico = new ImageIcon("gfx/test.png");
Test t = new Test(p, 20, 20, 400, 300, 101, ico);
f.getContentPane().add(t);
f.setSize(500, 400);
f.setLayout(null);
f.setVisible(true);
}
}
but i only get this output: output
My original picture was: wanted output

You can do so by overriding the contains(Point p) method to only return true when p is in the bounds of your custom shape.
Then you best override isOpaque() to return false.
And finally you override paintComponent(Graphics g) to paint your component in whatever way you like (e.g. a background image with colors in the shape and blank color in the rest).
Sample code:
JPanel panel = new JPanel()
{
#Override
public boolean isOpaque()
{
return false;
}
#Override
public boolean contains(Point p)
{
// Use something that fits your shape here.
return p.getX() % 2 == 0;
}
#Override
public void paintComponent(Graphics g)
{
// do some painting
}
};

Java JScrollBar Design

I want customize the JScrollBar Design. I use Mac to develop the app with eclipse. I already tried to scrollPane.getVerticalScrollBar().setBackground(Color.BLACK); but nothing happen.
My code:
scrollPane = new JScrollPane(scriptView);
scrollPane.setBorder(BorderFactory.createEmptyBorder());
scrollPane.getVerticalScrollBar().setUnitIncrement(6);
window.getContentPane().add(scrollPane);
The Object scriptView is from the class JEditorPane.
How it should look:
Thanks for every help.

I guess you are looking for a transparent scrollbar.
This is just presented as an idea(NOT tested code):
import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.plaf.basic.*;
public class TranslucentScrollBarTest {
public JComponent makeUI() {
JTextArea cmp = new JTextArea();
String str = "1234567890abcdefghijklmnopqrstuvwxyz";
for(int i=0; i<20; i++) {
cmp.append(str+str+"\n");
}
cmp.setForeground(Color.WHITE);
cmp.setBackground(Color.BLACK);
cmp.setOpaque(true);
JScrollPane scrollPane = new JScrollPane(
cmp, ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS,
ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
scrollPane.setComponentZOrder(scrollPane.getVerticalScrollBar(), 0);
scrollPane.setComponentZOrder(scrollPane.getViewport(), 1);
scrollPane.getVerticalScrollBar().setOpaque(false);
scrollPane.setLayout(new ScrollPaneLayout() {
#Override
public void layoutContainer(Container parent) {
JScrollPane scrollPane = (JScrollPane)parent;
Rectangle availR = scrollPane.getBounds();
availR.x = availR.y = 0;
Insets insets = parent.getInsets();
availR.x = insets.left;
availR.y = insets.top;
availR.width -= insets.left + insets.right;
availR.height -= insets.top + insets.bottom;
Rectangle vsbR = new Rectangle();
vsbR.width = 12;
vsbR.height = availR.height;
vsbR.x = availR.x + availR.width - vsbR.width;
vsbR.y = availR.y;
if(viewport != null) {
viewport.setBounds(availR);
}
if(vsb != null) {
vsb.setVisible(true);
vsb.setBounds(vsbR);
}
}
});
scrollPane.getVerticalScrollBar().setUI(new BasicScrollBarUI() {
private final Dimension d = new Dimension();
#Override protected JButton createDecreaseButton(int orientation) {
return new JButton() {
#Override public Dimension getPreferredSize() {
return d;
}
};
}
#Override protected JButton createIncreaseButton(int orientation) {
return new JButton() {
#Override public Dimension getPreferredSize() {
return d;
}
};
}
#Override
protected void paintTrack(Graphics g, JComponent c, Rectangle r) {}
#Override
protected void paintThumb(Graphics g, JComponent c, Rectangle r) {
Graphics2D g2 = (Graphics2D)g.create();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
Color color = null;
JScrollBar sb = (JScrollBar)c;
if(!sb.isEnabled() || r.width>r.height) {
return;
}else if(isDragging) {
color = new Color(200,200,100,200);
}else if(isThumbRollover()) {
color = new Color(255,255,100,200);
}else {
color = new Color(220,220,200,200);
}
g2.setPaint(color);
g2.fillRoundRect(r.x,r.y,r.width,r.height,10,10);
g2.setPaint(Color.WHITE);
g2.drawRoundRect(r.x,r.y,r.width,r.height,10,10);
g2.dispose();
}
#Override
protected void setThumbBounds(int x, int y, int width, int height) {
super.setThumbBounds(x, y, width, height);
scrollbar.repaint();
}
});
return scrollPane;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override public void run() {
createAndShowGUI();
}
});
}
public static void createAndShowGUI() {
JFrame f = new JFrame();
f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
f.getContentPane().add(new TranslucentScrollBarTest().makeUI());
f.setSize(320, 240);
f.setLocationRelativeTo(null);
f.setVisible(true);
}
}

Here is an improved version I did for a private project. It also supports horizontal scrollbar.
Code:
import javax.swing.*;
import javax.swing.plaf.basic.BasicScrollBarUI;
import java.awt.*;
/**
* This is an implementation of a JScrollPane with a modern UI
*
* #author Philipp Danner
*
*/
public class ModernScrollPane extends JScrollPane {
private static final long serialVersionUID = 8607734981506765935L;
private static final int SCROLL_BAR_ALPHA_ROLLOVER = 100;
private static final int SCROLL_BAR_ALPHA = 50;
private static final int THUMB_SIZE = 8;
private static final int SB_SIZE = 10;
private static final Color THUMB_COLOR = Color.Black;
public ModernScrollPane(Component view) {
this(view, VERTICAL_SCROLLBAR_AS_NEEDED, HORIZONTAL_SCROLLBAR_AS_NEEDED);
}
public ModernScrollPane(int vsbPolicy, int hsbPolicy) {
this(null, vsbPolicy, hsbPolicy);
}
public ModernScrollPane(Component view, int vsbPolicy, int hsbPolicy) {
setBorder(null);
// Set ScrollBar UI
JScrollBar verticalScrollBar = getVerticalScrollBar();
verticalScrollBar.setOpaque(false);
verticalScrollBar.setUI(new ModernScrollBarUI(this));
JScrollBar horizontalScrollBar = getHorizontalScrollBar();
horizontalScrollBar.setOpaque(false);
horizontalScrollBar.setUI(new ModernScrollBarUI(this));
setLayout(new ScrollPaneLayout() {
private static final long serialVersionUID = 5740408979909014146L;
#Override
public void layoutContainer(Container parent) {
Rectangle availR = ((JScrollPane) parent).getBounds();
availR.x = availR.y = 0;
// viewport
Insets insets = parent.getInsets();
availR.x = insets.left;
availR.y = insets.top;
availR.width -= insets.left + insets.right;
availR.height -= insets.top + insets.bottom;
if (viewport != null) {
viewport.setBounds(availR);
}
boolean vsbNeeded = isVerticalScrollBarfNecessary();
boolean hsbNeeded = isHorizontalScrollBarNecessary();
// vertical scroll bar
Rectangle vsbR = new Rectangle();
vsbR.width = SB_SIZE;
vsbR.height = availR.height - (hsbNeeded ? vsbR.width : 0);
vsbR.x = availR.x + availR.width - vsbR.width;
vsbR.y = availR.y;
if (vsb != null) {
vsb.setBounds(vsbR);
}
// horizontal scroll bar
Rectangle hsbR = new Rectangle();
hsbR.height = SB_SIZE;
hsbR.width = availR.width - (vsbNeeded ? hsbR.height : 0);
hsbR.x = availR.x;
hsbR.y = availR.y + availR.height - hsbR.height;
if (hsb != null) {
hsb.setBounds(hsbR);
}
}
});
// Layering
setComponentZOrder(getVerticalScrollBar(), 0);
setComponentZOrder(getHorizontalScrollBar(), 1);
setComponentZOrder(getViewport(), 2);
viewport.setView(view);
}
private boolean isVerticalScrollBarfNecessary() {
Rectangle viewRect = viewport.getViewRect();
Dimension viewSize = viewport.getViewSize();
return viewSize.getHeight() > viewRect.getHeight();
}
private boolean isHorizontalScrollBarNecessary() {
Rectangle viewRect = viewport.getViewRect();
Dimension viewSize = viewport.getViewSize();
return viewSize.getWidth() > viewRect.getWidth();
}
/**
* Class extending the BasicScrollBarUI and overrides all necessary methods
*/
private static class ModernScrollBarUI extends BasicScrollBarUI {
private JScrollPane sp;
public ModernScrollBarUI(ModernScrollPane sp) {
this.sp = sp;
}
#Override
protected JButton createDecreaseButton(int orientation) {
return new InvisibleScrollBarButton();
}
#Override
protected JButton createIncreaseButton(int orientation) {
return new InvisibleScrollBarButton();
}
#Override
protected void paintTrack(Graphics g, JComponent c, Rectangle trackBounds) {
}
#Override
protected void paintThumb(Graphics g, JComponent c, Rectangle thumbBounds) {
int alpha = isThumbRollover() ? SCROLL_BAR_ALPHA_ROLLOVER : SCROLL_BAR_ALPHA;
int orientation = scrollbar.getOrientation();
int x = thumbBounds.x;
int y = thumbBounds.y;
int width = orientation == JScrollBar.VERTICAL ? THUMB_SIZE : thumbBounds.width;
width = Math.max(width, THUMB_SIZE);
int height = orientation == JScrollBar.VERTICAL ? thumbBounds.height : THUMB_SIZE;
height = Math.max(height, THUMB_SIZE);
Graphics2D graphics2D = (Graphics2D) g.create();
graphics2D.setColor(new Color(THUMB_COLOR.getRed(), THUMB_COLOR.getGreen(), THUMB_COLOR.getBlue(), alpha));
graphics2D.fillRect(x, y, width, height);
graphics2D.dispose();
}
#Override
protected void setThumbBounds(int x, int y, int width, int height) {
super.setThumbBounds(x, y, width, height);
sp.repaint();
}
/**
* Invisible Buttons, to hide scroll bar buttons
*/
private static class InvisibleScrollBarButton extends JButton {
private static final long serialVersionUID = 1552427919226628689L;
private InvisibleScrollBarButton() {
setOpaque(false);
setFocusable(false);
setFocusPainted(false);
setBorderPainted(false);
setBorder(BorderFactory.createEmptyBorder());
}
}
}
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setPreferredSize(new Dimension(400, 400));
JPanel content = new JPanel();
content.setBackground(Color.WHITE);
content.setPreferredSize(new Dimension(500, 500));
content.add(new JLabel("test"));
frame.add(new ModernScrollPane(content));
frame.pack();
frame.setVisible(true);
}
}

Custom scrollbar preview :
Custom scrollbar code :
public class CustomScrollBarUI extends BasicScrollBarUI {
private final Dimension d = new Dimension();
#Override
protected JButton createDecreaseButton(int orientation) {
return new JButton() {
private static final long serialVersionUID = -3592643796245558676L;
#Override
public Dimension getPreferredSize() {
return d;
}
};
}
#Override
protected JButton createIncreaseButton(int orientation) {
return new JButton() {
private static final long serialVersionUID = 1L;
#Override
public Dimension getPreferredSize() {
return d;
}
};
}
#Override
protected void paintTrack(Graphics g, JComponent c, Rectangle r) {
}
#Override
protected void paintThumb(Graphics g, JComponent c, Rectangle r) {
Graphics2D g2 = (Graphics2D) g.create();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
Color color = null;
JScrollBar sb = (JScrollBar) c;
if (!sb.isEnabled() || r.width > r.height) {
return;
} else if (isDragging) {
color = Color.DARK_GRAY; // change color
} else if (isThumbRollover()) {
color = Color.LIGHT_GRAY; // change color
} else {
color = Color.GRAY; // change color
}
g2.setPaint(color);
g2.fillRoundRect(r.x, r.y, r.width, r.height, 10, 10);
g2.setPaint(Color.WHITE);
g2.drawRoundRect(r.x, r.y, r.width, r.height, 10, 10);
g2.dispose();
}
#Override
protected void setThumbBounds(int x, int y, int width, int height) {
super.setThumbBounds(x, y, width, height);
scrollbar.repaint();
}
}
Then use it like this:
YOUR_COMPONENT.getVerticalScrollBar().setUI(new CustomScrollBarUI());

Sadly the proposed solutions will break JTable and won't display the table header, but I found this solution that seems to work.

Unable to get rid of drawn lines

I found similar problems on the internet but the solutions provided didn't work.
I want to clear the JPanel. To do that I call repaint()(from the clear() method) with a flag set to false to avoid calling my drawing method (drawLines()). Drawn lines are still on the Panel.
I tried to repaint same lines again with the background color. This also didn't work.
public class WektPanel extends JPanel{
boolean check = false;
Color c = Color.BLUE;
boolean oval = false;
public WektPanel() {
setBackground(c);
setVisible(true);
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
if(check)
drawLines(3, g);
}
void clear(){
check=false;
repaint();
}
void draw(){
check=true;
repaint();
}
void drawLines(int stroke, Graphics g){
g.drawLine(0,0,getWidth(),getHeight());
g.drawLine(0,getHeight(),getWidth(),0);
for(int i=1; i<stroke;i++){
g.drawLine(0+i,0,getWidth(),getHeight()-i);
g.drawLine(0,0+i,getWidth()-i,getHeight());
g.drawLine(0,getHeight()-i,getWidth()-i,0);
g.drawLine(0+i,getHeight(),getWidth(),0+i);
}
}
}

You're overriding paint(), but calling super.paintComponent(g). You should override paintComponent(g).
Edit: I couldn't follow your check logic. This worked for me.
public class Test {
private class WektPanel extends JPanel {
boolean clear;
public WektPanel() {
setBackground(Color.BLUE);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(300, 200);
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
drawLines(3, g);
}
public void clear() {
clear = true;
repaint();
}
public void draw() {
clear = false;
repaint();
}
private void drawLines(int stroke, Graphics g) {
if (!clear) {
g.drawLine(0, 0, getWidth(), getHeight());
g.drawLine(0, getHeight(), getWidth(), 0);
for (int i = 1; i < stroke; i++) {
g.drawLine(0 + i, 0, getWidth(), getHeight() - i);
g.drawLine(0, 0 + i, getWidth() - i, getHeight());
g.drawLine(0, getHeight() - i, getWidth() - i, 0);
g.drawLine(0 + i, getHeight(), getWidth(), 0 + i);
}
}
}
}
private void showGUI() {
JFrame f = new JFrame("Test");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final WektPanel wektPanel = new WektPanel();
f.add(wektPanel, BorderLayout.CENTER);
JPanel buttonPanel = new JPanel();
buttonPanel.add(new JButton(new AbstractAction("Clear") {
#Override
public void actionPerformed(ActionEvent e) {
wektPanel.clear();
}
}));
buttonPanel.add(new JButton(new AbstractAction("Draw") {
#Override
public void actionPerformed(ActionEvent e) {
wektPanel.draw();
}
}));
f.add(buttonPanel, BorderLayout.SOUTH);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
new Test().showGUI();
}
});
}
}

The first line in the paint method should be something like:
g.clearRect(0, 0, getWidth(), getHeight());
This way you make sure that the previous paints will not be there when you start painting again.