Moving a JLabel Around JPanel

Moving a JLabel Around JPanel - java

I have a JPanel that has 2+ JLables on it, I would like to be able to grab a label then move it to a different location on the JPanel. How can I do that? The only things I can find on this are moving a label from component "A" to component "B", nothing about moving it around on a Panel.

Start playing with this:
public class ComponentDragger extends MouseAdapter {
private Component target;
/**
* {#inheritDoc}
*/
#Override
public void mousePressed(MouseEvent e) {
Container container = (Container) e.getComponent();
for (Component c : container.getComponents()) {
if (c.getBounds().contains(e.getPoint())) {
target = c;
break;
}
}
}
/**
* {#inheritDoc}
*/
#Override
public void mouseDragged(MouseEvent e) {
if (target != null) {
target.setBounds(e.getX(), e.getY(), target.getWidth(), target.getHeight());
e.getComponent().repaint();
}
}
/**
* {#inheritDoc}
*/
#Override
public void mouseReleased(MouseEvent e) {
target = null;
}
public static void main(String[] args) {
JLabel label = new JLabel("Drag Me");
JPanel panel = new JPanel();
panel.add(label);
ComponentDragger dragger = new ComponentDragger();
panel.addMouseListener(dragger);
panel.addMouseMotionListener(dragger);
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(1024, 768);
f.add(panel);
f.setVisible(true);
panel.setLayout(null);
f.setState(Frame.MAXIMIZED_BOTH);
}
}

Here's another example of this where the MouseListener and MouseMotionListener are on the JLabels themselves. For this to work, it needs to know the mouse's location on the screen vs it's initial location on screen when the mouse was initially pressed.
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Point;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.Random;
import javax.swing.*;
import javax.swing.border.Border;
import javax.swing.border.EmptyBorder;
import javax.swing.border.LineBorder;
public class MovingLabels {
private static final int PREF_W = 800;
private static final int PREF_H = 600;
private static void createAndShowGui() {
Random random = new Random();
final JPanel panel = new JPanel();
Color[] colors = {Color.red, Color.orange, Color.yellow, Color.green, Color.blue, Color.cyan};
panel.setPreferredSize(new Dimension(PREF_W, PREF_H)); // sorry kleopatra
panel.setLayout(null);
MyMouseAdapter myMouseAdapter = new MyMouseAdapter();
for (int i = 0; i < colors.length; i++) {
Color c = colors[i];
JLabel label = new JLabel("Label " + (i + 1));
Border outsideBorder = new LineBorder(Color.black);
int eb = 10;
Border insideBorder = new EmptyBorder(eb, eb, eb, eb);
label.setBorder(BorderFactory.createCompoundBorder(outsideBorder , insideBorder));
label.setSize(label.getPreferredSize());
label.setBackground(c);
label.setOpaque(true);
int x = random.nextInt(PREF_W - 200) + 100;
int y = random.nextInt(PREF_H - 200) + 100;
label.setLocation(x, y);
label.addMouseListener(myMouseAdapter);
label.addMouseMotionListener(myMouseAdapter);
panel.add(label);
}
JFrame frame = new JFrame("MovingLabels");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(panel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class MyMouseAdapter extends MouseAdapter {
private Point initialLoc;
private Point initialLocOnScreen;
#Override
public void mousePressed(MouseEvent e) {
Component comp = (Component)e.getSource();
initialLoc = comp.getLocation();
initialLocOnScreen = e.getLocationOnScreen();
}
#Override
public void mouseReleased(MouseEvent e) {
Component comp = (Component)e.getSource();
Point locOnScreen = e.getLocationOnScreen();
int x = locOnScreen.x - initialLocOnScreen.x + initialLoc.x;
int y = locOnScreen.y - initialLocOnScreen.y + initialLoc.y;
comp.setLocation(x, y);
}
#Override
public void mouseDragged(MouseEvent e) {
Component comp = (Component)e.getSource();
Point locOnScreen = e.getLocationOnScreen();
int x = locOnScreen.x - initialLocOnScreen.x + initialLoc.x;
int y = locOnScreen.y - initialLocOnScreen.y + initialLoc.y;
comp.setLocation(x, y);
}
}

You are probably getting it for the label itself. Try observing the coordinates of the panel. It should work

Here is what I wanted:
public class LayerItem extends JLabel{
protected int lblYPt = 0;
public LayerItem(JPanel layers){
this.addMouseListener(new MouseAdapter(){
#Override
public void mousePressed(MouseEvent evt){
lblMousePressed(evt);
}
});
this.addMouseMotionListener(new MouseAdapter(){
#Override
public void mouseDragged(MouseEvent evt){
lblMouseDragged(evt);
}
});
}
public void lblMousePressed(MouseEvent evt){
lblYPt = evt.getY();
}
public void lblMouseDragged(MouseEvent evt){
Component parent = evt.getComponent().getParent();
Point mouse = parent.getMousePosition();
try{
if(mouse.y - lblYPt >= 30){
this.setBounds(0, mouse.y - lblYPt, 198, 50);
}
}catch(Exception e){
}
}
}

Related

Draw Box works but Line does not

I create a project.When I press "New Box" I want to create a blue box.Then when I press 'Line' I want to draw a line and connect the lines and the box. I created box's codes and this is working but line's codes is not working. Actually line's codes is working another window/folder but not here working. Maybe I made a mistake when write a codes.
This Window and main codes..
public class Cerceve extends JFrame implements ActionListener {
JPanel MAINPANEL, LEFTPANEL, RIGHTPANEL;
JButton btnBox, btnClear;
DragListener drag = new DragListener();
JButton btnLine;
public Cerceve() {
// ÇERÇEVE OLUŞTUR
super("ÇİZGE PROGRAMI");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(1200, 700);
setResizable(false);
setLocationRelativeTo(null);
setVisible(true);
// ÜZERİNE BİLEŞENLERİ EKLE
setLayout(new BorderLayout());
MAINPANEL = new JPanel();
MAINPANEL.setBackground(Color.WHITE);
this.add(MAINPANEL, BorderLayout.CENTER);
MAINPANEL.setLayout(new BorderLayout());
LEFTPANEL = new JPanel();
LEFTPANEL.setBackground(Color.GRAY);
MAINPANEL.add(LEFTPANEL, BorderLayout.WEST);
RIGHTPANEL = new JPanel();
RIGHTPANEL.setBackground(Color.WHITE);
MAINPANEL.add(RIGHTPANEL, BorderLayout.CENTER);
btnBox = new JButton("New Box");
LEFTPANEL.add(btnBox);
btnClear = new JButton("Clear");
LEFTPANEL.add(btnClear);
btnLine = new JButton("Line");
LEFTPANEL.add(btnLine);
btnBox.addActionListener(this);
btnClear.addActionListener(this);
btnLine.addActionListener(this);
}
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == btnBox) {
Box box = new Box();
RIGHTPANEL.add(box);
RIGHTPANEL.repaint();
box.addMouseMotionListener(drag);
box.addMouseListener(drag);
}
else if (e.getSource() == btnClear) {
RIGHTPANEL.removeAll();
RIGHTPANEL.repaint();
}
else if (e.getSource() == btnLine) {
Line line = new Line();
RIGHTPANEL.repaint();
RIGHTPANEL.add(line);
line.addMouseListener(line.mouseHandler);
line.addMouseMotionListener(line.mouseMotionListener);
}
}
}
THİS İS BOX PACKAGE
public class Box extends JPanel {
public Box() {
setLayout(null);
setBackground(Color.BLUE);
setSize(50, 50);
setLocation(0, 0);
}
}
THİS İS DRAG LİSTENER PACKAGE
class DragListener extends MouseInputAdapter {
Point location;
MouseEvent mouseInfo;
#Override
public void mousePressed(MouseEvent me) {
mouseInfo = me;
}
#Override
public void mouseDragged(MouseEvent me) {
if (SwingUtilities.isLeftMouseButton(me) == true) {
Component component = me.getComponent();
location = component.getLocation(location);
int x = location.x - mouseInfo.getX() + me.getX();
int y = location.y - mouseInfo.getY() + me.getY();
component.setLocation(x, y);
}
}
}
THİS İS LİNE PACKAGE
public class Line extends JFrame {
private int xBegin = 0;
private int xEnd = 0;
private int yBegin = 0;
private int yEnd = 0;
public MouseListener mouseHandler = new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
xBegin = e.getX();
yBegin = e.getY();
repaint();
}
#Override
public void mouseReleased(MouseEvent e) {
xEnd = e.getX();
yEnd = e.getY();
repaint();
}
};
public MouseMotionListener mouseMotionListener = new MouseMotionAdapter() {
#Override
public void mouseDragged(MouseEvent e) {
xEnd = e.getX();
yEnd = e.getY();
repaint();
}
};
public void paint(Graphics g) {
super.paint(g);
g.drawLine(xBegin, yBegin, xEnd, yEnd);
}
}

Swap JPanels in an array of JPanels

I am able to SWAP the panels but it is not good enough. For instance, if panel1 collides panel2, it swaps, but if the same collides panel3, panel3 also moves to panel1 location(which I don't want to happen). If there are about 10 panels, and if I want to swap panel1 with panel10 it is not possible with current logic. Can anyone please help me out.
Below is the code with the above logic:
import javax.swing.border.LineBorder;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class GDragAndDrop extends JFrame {
public GDragAndDrop() {
add(new op());
}
public static void main(String[] args) {
GDragAndDrop frame = new GDragAndDrop();
frame.setTitle("GDragAndDrop");
frame.setSize(600, 600);
frame.setLocationRelativeTo(null);// Center the frame
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
class op extends JPanel implements MouseListener, MouseMotionListener {
JPanel p;
Point pPoint;
Point p1;
Point p2;
MouseEvent pressed;
JPanel[] panels = new JPanel[3];
public op() {
int b = 3;
int a = 0;
for (int i = 0; i < b; i++) {
panels[i] = new JPanel();
panels[i].setBackground(Color.cyan);
panels[i].setBorder(new LineBorder(Color.black));
a = a + 20;
panels[i].setPreferredSize(new Dimension(a, 400));
panels[i].addMouseListener(this);
panels[i].addMouseMotionListener(this);
panels[i].setBorder(new LineBorder(Color.black));
panels[i].setVisible(true);
panels[i].add("Center", new JLabel("To Move" + i));
this.add(panels[i]);
}
}
public JPanel getPanelColliding(JPanel dragPanel) {
Rectangle rDrag = dragPanel.getBounds();
for (int i = 0; i < 3; i++) {
if (panels[i] == dragPanel)
continue;
Rectangle r = panels[i].getBounds();
if (r.intersects(rDrag)) {
return panels[i];
}
}
return null;
}
public void mousePressed(MouseEvent e) {
int b = 3;
for (int i = 0; i < b; i++) {
if (e.getSource() == panels[i]) {
pressed = e;
p2 = panels[i].getLocation();
}
}
}
#Override
public void mouseDragged(MouseEvent arg0) {
int b = 3;
for (int i = 0; i < b; i++) {
if (arg0.getSource() == panels[i]) {
pPoint = panels[i].getLocation(pPoint);
int x = pPoint.x - pressed.getX() + arg0.getX();
int y = pPoint.y - pressed.getY() + arg0.getY();
if (getPanelColliding(panels[i]) != null) {
JPanel DragP = new JPanel();
DragP = getPanelColliding(panels[i]);
p1 = getPanelColliding(panels[i]).getLocation(p1);
int x1 = pPoint.x - pressed.getX() + arg0.getX();
int y1 = pPoint.y - pressed.getY() + arg0.getY();
panels[i].setLocation(x1, y1);
DragP.setLocation(p2);
} else
panels[i].setLocation(x, y);
}
}
}
#Override
public void mouseClicked(MouseEvent e) {
}
#Override
public void mouseReleased(MouseEvent e) {
}
#Override
public void mouseEntered(MouseEvent e) {
}
#Override
public void mouseExited(MouseEvent e) {
}
#Override
public void mouseMoved(MouseEvent e) {
}
}

If you don't want to use drag-and-drop, and if your JPanels are in columns, then consider these suggestions:
I've gotten this to work having the container JPanel (the one that holds the multiple column components) use a FlowLayout
I've added the MouseAdapter as a MouseListener and MouseMotionListener to the container JPanel, not the column components.
I obtained the selected column component by calling getComponentAt(mouseEvent.getPoint()) on the container JPanel. Of course check that it's not null.
If the selected component is not null, then I set a selectedComponent variable with this component, and put a placeholder JLabel that has the same preferredSize in its place. I do this by removing all components from the container JPanel, and then re-adding them all back except for the selected component where I instead add the placeholder JLabel. I then call revalidate and repaint on the container.
To drag the selected component, elevate it to the glassPane (i.e., add it to the glassPane).
make the glassPane visible and give it a null layout.
Drag the selected component in the glassPane simply by changing its location relative to the glassPane.
On mouseReleased, find out what column component the mouse is over, again by using getComponentAt(...).
Then remove all components from the container JPanel,
and then add them all back in the desired order.
Then again call revalidate and repaint on the container JPanel.
For example:
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridBagLayout;
import java.awt.Point;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.*;
public class SwapPanelEg extends JPanel {
private static final long serialVersionUID = 1594039652438249918L;
private static final int PREF_W = 400;
private static final int PREF_H = 400;
private static final int MAX_COLUMN_PANELS = 8;
private JPanel columnPanelsHolder = new JPanel();
public SwapPanelEg() {
columnPanelsHolder.setLayout(new FlowLayout(FlowLayout.CENTER, 5, 5));
for (int i = 0; i < MAX_COLUMN_PANELS; i++) {
int number = i + 1;
int width = 20 + i * 3;
int height = PREF_H - 30;
columnPanelsHolder.add(new ColumnPanel(number, width, height));
}
MyMouseAdapter myMouseAdapter = new MyMouseAdapter();
columnPanelsHolder.addMouseListener(myMouseAdapter);
columnPanelsHolder.addMouseMotionListener(myMouseAdapter);
setLayout(new GridBagLayout());
add(columnPanelsHolder);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
private class MyMouseAdapter extends MouseAdapter {
private JComponent selectedPanel;
private Point deltaLocation;
private JLabel placeHolder = new JLabel();
private JComponent glassPane;
#Override
public void mousePressed(MouseEvent evt) {
if (evt.getButton() != MouseEvent.BUTTON1) {
return;
}
JPanel source = (JPanel) evt.getSource();
selectedPanel = (JComponent) source.getComponentAt(evt.getPoint());
if (selectedPanel == null) {
return;
}
if (selectedPanel == source) {
selectedPanel = null;
return;
}
glassPane = (JComponent) SwingUtilities.getRootPane(source).getGlassPane();
glassPane.setVisible(true);
Point glassPaneOnScreen = glassPane.getLocationOnScreen();
glassPane.setLayout(null);
Point ptOnScreen = evt.getLocationOnScreen();
Point panelLocOnScreen = selectedPanel.getLocationOnScreen();
int deltaX = ptOnScreen.x + glassPaneOnScreen.x - panelLocOnScreen.x;
int deltaY = ptOnScreen.y + glassPaneOnScreen.y - panelLocOnScreen.y;
deltaLocation = new Point(deltaX, deltaY);
Component[] allComps = source.getComponents();
for (Component component : allComps) {
source.remove(component);
if (component == selectedPanel) {
placeHolder.setPreferredSize(selectedPanel.getPreferredSize());
source.add(placeHolder);
selectedPanel.setSize(selectedPanel.getPreferredSize());
int x = ptOnScreen.x - deltaLocation.x;
int y = ptOnScreen.y - deltaLocation.y;
selectedPanel.setLocation(x, y);
glassPane.add(selectedPanel);
} else {
source.add(component);
}
}
revalidate();
repaint();
}
#Override
public void mouseDragged(MouseEvent evt) {
if (selectedPanel != null) {
Point ptOnScreen = evt.getLocationOnScreen();
int x = ptOnScreen.x - deltaLocation.x;
int y = ptOnScreen.y - deltaLocation.y;
selectedPanel.setLocation(x, y);
repaint();
}
}
#Override
public void mouseReleased(MouseEvent evt) {
if (evt.getButton() != MouseEvent.BUTTON1) {
return;
}
if (selectedPanel == null) {
return;
}
JComponent source = (JComponent) evt.getSource();
Component[] allComps = source.getComponents();
Component overComponent = (JComponent) source.getComponentAt(evt
.getPoint());
source.removeAll();
if (overComponent != null && overComponent != placeHolder
&& overComponent != source) {
for (Component component : allComps) {
if (component == placeHolder) {
source.add(overComponent);
} else if (component == overComponent) {
source.add(selectedPanel);
} else {
source.add(component);
}
}
} else {
for (Component component : allComps) {
if (component == placeHolder) {
source.add(selectedPanel);
} else {
source.add(component);
}
}
}
revalidate();
repaint();
selectedPanel = null;
}
}
private static void createAndShowGui() {
SwapPanelEg mainPanel = new SwapPanelEg();
JFrame frame = new JFrame("SwapPanelEg");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class ColumnPanel extends JPanel {
private static final long serialVersionUID = 5366233209639059032L;
private int number;
private int prefWidth;
private int prefHeight;
public ColumnPanel(int number, int prefWidth, int prefHeight) {
setName("ColumnPanel " + number);
this.number = number;
this.prefWidth = prefWidth;
this.prefHeight = prefHeight;
add(new JLabel(String.valueOf(number)));
setBorder(BorderFactory.createLineBorder(Color.black));
setBackground(Color.cyan);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(prefWidth, prefHeight);
}
public int getNumber() {
return number;
}
}

If you don't want to use Swing drag-and-drop, swap the content of the source and destination, as shown in this JLayeredPane example and variation.

Something seems wrong with the layout, JButton showing unexpected behaviour at resize of the window

JRE Version 1.7 Update 3
EXPECTED BEHAVIOUR
As I run the program, it works as expected, everything works smoothly. As when I click on STOP JButton the animation stops and the text on the same JButton changes to START. Now when i click on BALL COLOUR JButton, the colour of the BALL changes, as well as the colour of the BALL COLOUR JBUTTON, also changes, to that of the BALL. This whole behaviour works if I run my application as is without resizing.
UNEXPECTED BEHAVIOUR
But when i RESIZE my JFrame, by pulling the Right Side, that's when unexpected behaviour of my Application is shown, in the sense that if I press STOP JButton and then click on BALL COLOUR button, the text on the JButton clicked earlier whose text changed to START will change to STOP again when it should not be, as well as the colour of the BALL COLOUR JButton will remain unchanged or will turn to BLUE, when it should be changed to the colour of the ball. I am attaching the pics for more info. But if you will try to resize it back to it's original size or closer to that, then things will come back to normal. Why is this happening ? Any idea or clue will be much appreciated.
As My Application Runs with EXPECTED BEHAVIOUR as described above :
And here the UNEXPECTED BEHAVIOUR
BOTTOM-LINE :
Why the Application runs as usual as it should be, at the BEGINNING , but not when RESIZED by dragging it's RIGHT SIDE, but again if you bring it to it's original size or closer to it, things come back to normal, it works as expected ?
So considering the scenario, am I doing something wrong, in the program. Or is this exactly the situation, where I should be using the SwingWorker, Or Is this an issue with the Layout, or something hidden related to Content Pane. Please do put some light :-)
here is the code I am using, I had brought it down to the minimum, as I think to demonstrate my problem :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class BallAnimation
{
private int x;
private int y;
private boolean positiveX;
private boolean positiveY;
private boolean isTimerRunning;
private int speedValue;
private int diameter;
private DrawingArea drawingArea;
private Timer timer;
private int colourCounter;
Color[] colours = {
Color.BLUE.darker(),
Color.MAGENTA.darker(),
Color.BLACK.darker(),
Color.RED.darker(),
Color.PINK.darker(),
Color.CYAN.darker(),
Color.DARK_GRAY.darker(),
Color.YELLOW.darker(),
Color.GREEN.darker()
};
private Color backgroundColour;
private Color foregroundColour;
private ActionListener timerAction = new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
x = getX();
y = getY();
drawingArea.setXYColourValues(x, y, backgroundColour
, foregroundColour);
}
};
private JPanel buttonPanel;
private JButton startStopButton;
private JButton speedIncButton;
private JButton speedDecButton;
private JButton resetButton;
private JButton colourButton;
private JButton exitButton;
private ComponentAdapter componentAdapter = new ComponentAdapter()
{
public void componentResized(ComponentEvent ce)
{
timer.restart();
startStopButton.setText("STOP");
isTimerRunning = true;
}
};
public BallAnimation()
{
x = y = 0;
positiveX = positiveY = true;
speedValue = 1;
colourCounter = 0;
isTimerRunning = false;
diameter = 50;
backgroundColour = Color.WHITE.brighter();
foregroundColour = colours[colourCounter];
timer = new Timer(10, timerAction);
}
private void createAndDisplayGUI()
{
JFrame frame = new JFrame("Ball Animation");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationByPlatform(true);
drawingArea = new DrawingArea(x, y
, backgroundColour, foregroundColour, diameter);
drawingArea.addComponentListener(componentAdapter);
frame.add(makeButtonPanel(), BorderLayout.LINE_END);
frame.add(drawingArea, BorderLayout.CENTER);
frame.pack();
frame.setVisible(true);
}
private JPanel makeButtonPanel()
{
buttonPanel = new JPanel();
buttonPanel.setLayout(new GridLayout(0, 1));
buttonPanel.setBorder(BorderFactory.createLineBorder(
Color.DARK_GRAY, 5, true));
startStopButton = new JButton("START");
startStopButton.setBackground(Color.GREEN.darker());
startStopButton.setForeground(Color.WHITE.brighter());
startStopButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
System.out.println("START/STOP JButton Clicked!");
if (!isTimerRunning)
{
startStopButton.setText("STOP");
timer.start();
isTimerRunning = true;
buttonPanel.revalidate();
buttonPanel.repaint();
}
else if (isTimerRunning)
{
startStopButton.setText("START");
timer.stop();
isTimerRunning = false;
buttonPanel.revalidate();
buttonPanel.repaint();
}
}
});
startStopButton.setBorder(BorderFactory.createLineBorder(
Color.WHITE, 4, true));
buttonPanel.add(startStopButton);
colourButton = new JButton("BALL COLOUR");
colourButton.setBackground(colours[colourCounter]);
colourButton.setForeground(Color.WHITE);
colourButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
System.out.println("COLOUR JButton Clicked!");
//timer.restart();
colourCounter++;
if (colourCounter == 9)
colourCounter = 0;
foregroundColour = colours[colourCounter];
drawingArea.setXYColourValues(x, y, backgroundColour
, foregroundColour);
//drawingArea.setForegroundForBall(foregroundColour);
colourButton.setBackground(foregroundColour);
colourButton.revalidate();
colourButton.repaint();
//timer.start();
}
});
colourButton.setBorder(BorderFactory.createLineBorder(
Color.WHITE, 2, true));
buttonPanel.add(colourButton);
exitButton = new JButton("EXIT");
exitButton.setBackground(Color.RED.darker());
exitButton.setForeground(Color.WHITE.brighter());
exitButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
System.out.println("EXIT JButton Clicked!");
timer.stop();
System.exit(0);
}
});
exitButton.setBorder(BorderFactory.createLineBorder(
Color.RED.darker().darker(), 4, true));
buttonPanel.add(exitButton);
return buttonPanel;
}
private int getX()
{
if (x < 0)
positiveX = true;
else if (x >= drawingArea.getWidth() - diameter)
positiveX = false;
return (calculateX());
}
private int calculateX()
{
if (positiveX)
return (x += speedValue);
else
return (x -= speedValue);
}
private int getY()
{
if (y < 0)
positiveY = true;
else if (y >= drawingArea.getHeight() - diameter)
positiveY = false;
return (calculateY());
}
private int calculateY()
{
if (positiveY)
return (y += speedValue);
else
return (y -= speedValue);
}
public static void main(String... args)
{
Runnable runnable = new Runnable()
{
public void run()
{
new BallAnimation().createAndDisplayGUI();
}
};
SwingUtilities.invokeLater(runnable);
}
}
class DrawingArea extends JComponent
{
private int x;
private int y;
private int ballDiameter;
private Color backgroundColor;
private Color foregroundColor;
public DrawingArea(int x, int y
, Color bColor, Color fColor, int dia)
{
this.x = x;
this.y = y;
ballDiameter = dia;
backgroundColor = bColor;
foregroundColor = fColor;
setBorder(BorderFactory.createLineBorder(
Color.DARK_GRAY.darker(), 5, true));
}
public void setXYColourValues(int x, int y
, Color bColor, Color fColor)
{
this.x = x;
this.y = y;
backgroundColor = bColor;
foregroundColor = fColor;
repaint();
}
public Dimension getPreferredSize()
{
return (new Dimension(500, 400));
}
public void paintComponent(Graphics g)
{
g.setColor(backgroundColor);
g.fillRect(0, 0, getWidth(), getHeight());
g.setColor(foregroundColor);
g.fillOval(x, y, ballDiameter, ballDiameter);
}
}
**LATEST EDIT : **

The problem with your very nice example may be platform dependent, but I can offer a few observations:
You're not adding or removing components, so you don't need revalidate().
Because the background color is a bound property of the buttons, you don't need the subsequent calls to repaint().
You do need repaint() in your custom DrawingArea, but you may want to experiment with adding property change support, as suggested here.
Color.white can't be brighter() and Color.black can't be darker(); Color.darkGray.darker() is Color.black().
The variation below uses a Queue<Color> to simplify changing colors.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.Queue;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
/** #see https://stackoverflow.com/q/9849950/230513 */
public class BallAnimation {
private int x;
private int y;
private boolean positiveX;
private boolean positiveY;
private boolean isTimerRunning;
private int speedValue;
private int diameter;
private DrawingArea drawingArea;
private Timer timer;
private Queue<Color> clut = new LinkedList<Color>(Arrays.asList(
Color.BLUE.darker(),
Color.MAGENTA.darker(),
Color.BLACK,
Color.RED.darker(),
Color.PINK,
Color.CYAN.darker(),
Color.DARK_GRAY,
Color.YELLOW.darker(),
Color.GREEN.darker()));
private Color backgroundColour;
private Color foregroundColour;
private ActionListener timerAction = new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
x = getX();
y = getY();
drawingArea.setXYColourValues(x, y, backgroundColour, foregroundColour);
}
};
private JPanel buttonPanel;
private JButton startStopButton;
private JButton speedIncButton;
private JButton speedDecButton;
private JButton resetButton;
private JButton colourButton;
private JButton exitButton;
private ComponentAdapter componentAdapter = new ComponentAdapter() {
#Override
public void componentResized(ComponentEvent ce) {
timer.restart();
startStopButton.setText("Stop");
isTimerRunning = true;
}
};
public BallAnimation() {
x = y = 0;
positiveX = positiveY = true;
speedValue = 1;
isTimerRunning = false;
diameter = 50;
backgroundColour = Color.white;
foregroundColour = clut.peek();
timer = new Timer(10, timerAction);
}
private void createAndDisplayGUI() {
JFrame frame = new JFrame("Ball Animation");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationByPlatform(true);
drawingArea = new DrawingArea(x, y, backgroundColour, foregroundColour, diameter);
drawingArea.addComponentListener(componentAdapter);
frame.add(makeButtonPanel(), BorderLayout.LINE_END);
frame.add(drawingArea, BorderLayout.CENTER);
frame.pack();
frame.setVisible(true);
}
private JPanel makeButtonPanel() {
buttonPanel = new JPanel(new GridLayout(0, 1));
buttonPanel.setBorder(BorderFactory.createLineBorder(Color.darkGray, 5));
startStopButton = new JButton("Start");
startStopButton.setOpaque(true);
startStopButton.setForeground(Color.white);
startStopButton.setBackground(Color.green.darker());
startStopButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
if (!isTimerRunning) {
startStopButton.setText("Stop");
timer.start();
isTimerRunning = true;
} else if (isTimerRunning) {
startStopButton.setText("Start");
timer.stop();
isTimerRunning = false;
}
}
});
startStopButton.setBorder(BorderFactory.createLineBorder(Color.gray, 4));
buttonPanel.add(startStopButton);
colourButton = new JButton("Change Color");
colourButton.setOpaque(true);
colourButton.setForeground(Color.white);
colourButton.setBackground(clut.peek());
colourButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
//timer.restart();
clut.add(clut.remove());
foregroundColour = clut.peek();
drawingArea.setXYColourValues(x, y, backgroundColour, foregroundColour);
colourButton.setBackground(foregroundColour);
}
});
colourButton.setBorder(BorderFactory.createLineBorder(Color.gray, 4));
buttonPanel.add(colourButton);
exitButton = new JButton("Exit");
exitButton.setBackground(Color.red);
exitButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
timer.stop();
System.exit(0);
}
});
exitButton.setBorder(BorderFactory.createLineBorder(Color.red.darker(), 4));
buttonPanel.add(exitButton);
return buttonPanel;
}
private int getX() {
if (x < 0) {
positiveX = true;
} else if (x >= drawingArea.getWidth() - diameter) {
positiveX = false;
}
return (calculateX());
}
private int calculateX() {
if (positiveX) {
return (x += speedValue);
} else {
return (x -= speedValue);
}
}
private int getY() {
if (y < 0) {
positiveY = true;
} else if (y >= drawingArea.getHeight() - diameter) {
positiveY = false;
}
return (calculateY());
}
private int calculateY() {
if (positiveY) {
return (y += speedValue);
} else {
return (y -= speedValue);
}
}
public static void main(String... args) {
Runnable runnable = new Runnable() {
#Override
public void run() {
new BallAnimation().createAndDisplayGUI();
}
};
SwingUtilities.invokeLater(runnable);
}
}
class DrawingArea extends JComponent {
private int x;
private int y;
private int ballDiameter;
private Color backgroundColor;
private Color foregroundColor;
public DrawingArea(int x, int y, Color bColor, Color fColor, int dia) {
this.x = x;
this.y = y;
ballDiameter = dia;
backgroundColor = bColor;
foregroundColor = fColor;
setBorder(BorderFactory.createLineBorder(Color.DARK_GRAY, 5));
}
public void setXYColourValues(int x, int y, Color bColor, Color fColor) {
this.x = x;
this.y = y;
backgroundColor = bColor;
foregroundColor = fColor;
repaint();
}
#Override
public Dimension getPreferredSize() {
return (new Dimension(500, 400));
}
#Override
public void paintComponent(Graphics g) {
g.setColor(backgroundColor);
g.fillRect(0, 0, getWidth(), getHeight());
g.setColor(foregroundColor);
g.fillOval(x, y, ballDiameter, ballDiameter);
}
}

Seems like there is something wrong with BorderLayout.LINE_END thingy, only when I place the buttonPanel on LINE_END, I am getting undesirable results. I had tried to use only one JButton, instead of three as the latest measure, to sort out thingies. Now the problem that use to come as shown in this pic :
has been sorted out by changing the position of the JButton Panel to LINE_START or using JRE version 1.6 update 31, in the pic as below :
Here is the code used for this example :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class BallAnimation
{
private int x;
private int y;
private boolean positiveX;
private boolean positiveY;
private boolean isTimerRunning;
private int speedValue;
private int diameter;
private DrawingArea drawingArea;
private Timer timer;
private int colourCounter;
Color[] colours = {
Color.BLUE.darker(),
Color.MAGENTA.darker(),
Color.BLACK.darker(),
Color.RED.darker(),
Color.PINK.darker(),
Color.CYAN.darker(),
Color.DARK_GRAY.darker(),
Color.YELLOW.darker(),
Color.GREEN.darker()
};
private Color backgroundColour;
private Color foregroundColour;
private ActionListener timerAction = new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
x = getX();
y = getY();
drawingArea.setXYColourValues(x, y, backgroundColour
, foregroundColour);
}
};
private JPanel buttonPanel;
private JButton startStopButton;
private JButton speedIncButton;
private JButton speedDecButton;
private JButton resetButton;
private JButton colourButton;
private JButton exitButton;
private ComponentAdapter componentAdapter = new ComponentAdapter()
{
public void componentResized(ComponentEvent ce)
{
timer.restart();
}
};
public BallAnimation()
{
x = y = 0;
positiveX = positiveY = true;
speedValue = 1;
colourCounter = 0;
isTimerRunning = false;
diameter = 50;
backgroundColour = Color.WHITE.brighter();
foregroundColour = colours[colourCounter];
timer = new Timer(10, timerAction);
}
private void createAndDisplayGUI()
{
JFrame frame = new JFrame("Ball Animation");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationByPlatform(true);
drawingArea = new DrawingArea(x, y
, backgroundColour, foregroundColour, diameter);
drawingArea.addComponentListener(componentAdapter);
frame.add(makeButtonPanel(), BorderLayout.LINE_START);
frame.add(drawingArea, BorderLayout.CENTER);
frame.pack();
frame.setVisible(true);
}
private JPanel makeButtonPanel()
{
buttonPanel = new JPanel();
buttonPanel.setLayout(new GridLayout(0, 1));
buttonPanel.setBorder(BorderFactory.createLineBorder(
Color.DARK_GRAY, 5, true));
colourButton = new JButton("BALL COLOUR");
colourButton.setOpaque(true);
colourButton.setBackground(colours[colourCounter]);
colourButton.setForeground(Color.WHITE);
colourButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
System.out.println("COLOUR JButton Clicked!");
if (timer.isRunning())
timer.stop();
colourCounter++;
if (colourCounter == 9)
colourCounter = 0;
foregroundColour = colours[colourCounter];
drawingArea.setXYColourValues(x, y, backgroundColour
, foregroundColour);
colourButton.setBackground(foregroundColour);
if (!timer.isRunning())
timer.start();
}
});
colourButton.setBorder(BorderFactory.createLineBorder(
Color.WHITE, 2, true));
buttonPanel.add(colourButton);
return buttonPanel;
}
private int getX()
{
if (x < 0)
positiveX = true;
else if (x >= drawingArea.getWidth() - diameter)
positiveX = false;
return (calculateX());
}
private int calculateX()
{
if (positiveX)
return (x += speedValue);
else
return (x -= speedValue);
}
private int getY()
{
if (y < 0)
positiveY = true;
else if (y >= drawingArea.getHeight() - diameter)
positiveY = false;
return (calculateY());
}
private int calculateY()
{
if (positiveY)
return (y += speedValue);
else
return (y -= speedValue);
}
public static void main(String... args)
{
Runnable runnable = new Runnable()
{
public void run()
{
new BallAnimation().createAndDisplayGUI();
}
};
SwingUtilities.invokeLater(runnable);
}
}
class DrawingArea extends JComponent
{
private int x;
private int y;
private int ballDiameter;
private Color backgroundColor;
private Color foregroundColor;
public DrawingArea(int x, int y
, Color bColor, Color fColor, int dia)
{
this.x = x;
this.y = y;
ballDiameter = dia;
backgroundColor = bColor;
foregroundColor = fColor;
setBorder(BorderFactory.createLineBorder(
Color.DARK_GRAY.darker(), 5, true));
}
public void setXYColourValues(int x, int y
, Color bColor, Color fColor)
{
this.x = x;
this.y = y;
backgroundColor = bColor;
foregroundColor = fColor;
repaint();
}
public Dimension getPreferredSize()
{
return (new Dimension(500, 400));
}
public void paintComponent(Graphics g)
{
g.setColor(backgroundColor);
g.fillRect(0, 0, getWidth(), getHeight());
g.setColor(foregroundColor);
g.fillOval(x, y, ballDiameter, ballDiameter);
}
}

maybe will help you with two parts of, I think that Graphics/2D is designated to use Swing Timer exclusively,

I am unsure whether I found a solution for your system, but adjusting the code to
colourButton = new JButton( "BALL COLOUR" );
colourButton.setOpaque( true );
colourButton.setBackground( colours[ colourCounter ] );
colourButton.setForeground( Color.WHITE );
works on my system (OS X with Java 1.7). Note the setOpaque call, which is needed so that the setBackground call has any effect as stated in the javadoc of that method:
Sets the background color of this component. The background color is used only if the component is opaque
On OS X, without that setOpaque call your code does not even work before a resize

Java: JSplitPane duplicates top panel's contents to bottom panel when Timer is active

So I have a JSplitPane, and two JPanels - one on top, one on the bottom. In both panels I overrode the paintComponent method and added my own graphics. In the bottom panel, I wanted to add an animation. When the panel does not repaint, it's fine, but as soon as the Timer (javax.swing.Timer) starts to call repaints, the bottom panel mimics the appearance of the top panel and glitches out. The actual animations are not refreshed, but rather it keeps on adding (like a dragged paintbrush instead of a moving object).
Here's the code for the Bottom Panel class:
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.JPanel;
import javax.swing.Timer;
public class WaitControls extends JPanel {
private int pos;
public WaitControls(){
setBackground(Color.gray);
pos = 0;
}
public void progress(){
//animation timer:
Timer timer = new Timer(30, new ActionListener(){
#Override
public void actionPerformed(ActionEvent e) {
pos++;
repaint();
}
});
timer.start();
}
#Override
public void paintComponent(Graphics g){
g.fillRect(pos, pos, 10, 20);
}
}
And here's the code for the Splitpane class:
//my classes (imported packages)
import rcc.controls.ControlPanel;
import rcc.controls.InitControls;
import rcc.controls.WaitControls;
import rcc.video.Screen;
import javax.swing.JSplitPane;
public class MainPanel extends JSplitPane{
public RCC rcc;
public Screen screen;
private int height;
public ControlPanel curPanel;
public MainPanel(RCC rcc, Screen screen, int height){
super(JSplitPane.VERTICAL_SPLIT);
this.rcc = rcc;
this.screen = screen;
this.height = height;
setDividerSize(2);
setEnabled(false);
setTopComponent(screen);
setToInitControls();
}
//sets the control panel to init controls ***WORKS FINE***
public void setToInitControls(){
InitControls initCtrls = new InitControls(this);
setBottomComponent(initCtrls);
curPanel = initCtrls;
setDividerLocation(height / 4 * 3);
}
//sets the control panel to wait controls (trying to connect) ***GLITCHES***
public void setToWaitControls(){
WaitControls waitCtrls = new WaitControls();
setBottomComponent(waitCtrls);
curPanel = waitCtrls;
setDividerLocation(height / 4 * 3);
waitCtrls.progress();
}
}
The top panel is a bit complicated. It involves mouse action (including a MouseEntered listener) and animates to interact with user mouse input.
The strange thing is, I have another bottom panel that was swapped out that also uses animations, and a timer, and does not have this glitch.
Any ideas what may have caused this? Thank you for all your help!

I can't imagine how your animations works,
1/ but if animation(s) depends of by any of Listener then Timer must be Timer#restart();
2/ check (example), how to pass addNotify()/removeNotify() for start/stop animatiom(s)
NOTE required fullHD monitor for better output or change code line
for (int iPanels = 0; iPanels < 3; iPanels++) {
to
for (int iPanels = 0; iPanels < 2; iPanels++) {
Example:
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
public class AnimationBackground {
public AnimationBackground() {
Random random = new Random();
JFrame frame = new JFrame("Animation Background");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
frame.setLayout(new GridLayout(0, 3, 10, 10));
for (int iPanels = 0; iPanels < 3; iPanels++) {
final MyJPanel panel = new MyJPanel();
panel.setBackground(Color.BLACK);
for (int i = 0; i < 50; i++) {
Star star = new Star(new Point(random.nextInt(490), random.nextInt(490)));
star.setColor(new Color(100 + random.nextInt(155), 100 + random.nextInt(155), 100 + random.nextInt(155)));
star.setxIncr(-3 + random.nextInt(7));
star.setyIncr(-3 + random.nextInt(7));
panel.add(star);
}
panel.setLayout(new GridLayout(10, 1));
JLabel label = new JLabel("This is a Starry background.", JLabel.CENTER);
label.setForeground(Color.WHITE);
panel.add(label);
JPanel stopPanel = new JPanel();
stopPanel.setOpaque(false);
stopPanel.add(new JButton(new AbstractAction("Stop this madness!!") {
private static final long serialVersionUID = 1L;
#Override
public void actionPerformed(ActionEvent e) {
panel.stopAnimation();
}
}));
panel.add(stopPanel);
JPanel startPanel = new JPanel();
startPanel.setOpaque(false);
startPanel.add(new JButton(new AbstractAction("Start moving...") {
private static final long serialVersionUID = 1L;
#Override
public void actionPerformed(ActionEvent e) {
panel.startAnimation();
}
}));
panel.add(startPanel);
frame.add(panel);
}
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
AnimationBackground animationBackground = new AnimationBackground();
}
});
}
class Star extends Polygon {
private static final long serialVersionUID = 1L;
private Point location = null;
private Color color = Color.YELLOW;
private int xIncr, yIncr;
static final int WIDTH = 500, HEIGHT = 500;
Star(Point location) {
int x = location.x;
int y = location.y;
this.location = location;
this.addPoint(x, y + 8);
this.addPoint(x + 8, y + 8);
this.addPoint(x + 11, y);
this.addPoint(x + 14, y + 8);
this.addPoint(x + 22, y + 8);
this.addPoint(x + 17, y + 12);
this.addPoint(x + 21, y + 20);
this.addPoint(x + 11, y + 14);
this.addPoint(x + 3, y + 20);
this.addPoint(x + 6, y + 12);
}
public void setColor(Color color) {
this.color = color;
}
public void move() {
if (location.x < 0 || location.x > WIDTH) {
xIncr = -xIncr;
}
if (location.y < 0 || location.y > WIDTH) {
yIncr = -yIncr;
}
translate(xIncr, yIncr);
location.setLocation(location.x + xIncr, location.y + yIncr);
}
public void setxIncr(int xIncr) {
this.xIncr = xIncr;
}
public void setyIncr(int yIncr) {
this.yIncr = yIncr;
}
public Color getColor() {
return color;
}
}
class MyJPanel extends JPanel {
private static final long serialVersionUID = 1L;
private ArrayList<Star> stars = new ArrayList<Star>();
private Timer timer = new Timer(20, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
for (Star star : stars) {
star.move();
}
repaint();
}
});
public void stopAnimation() {
if (timer.isRunning()) {
timer.stop();
}
}
public void startAnimation() {
if (!timer.isRunning()) {
timer.start();
}
}
#Override
public void addNotify() {
super.addNotify();
timer.start();
}
#Override
public void removeNotify() {
super.removeNotify();
timer.stop();
}
MyJPanel() {
this.setPreferredSize(new Dimension(520, 520));
}
public void add(Star star) {
stars.add(star);
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
((Graphics2D) g).setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
for (Star star : stars) {
g.setColor(star.getColor());
g.fillPolygon(star);
}
}
}
}

Problem with extending class JLabel to add to it property dragging

I have class JLabelExtended, which extends class javax.swing.JLabel.
I extend it, because I want to add property dragging using mouse.
Here is my code:
public class JLabelExtended extends JLabel {
private MouseMotionAdapter mouseMotionAdapter;
private JLabelExtended jLabelExtended;
public LabelEasy(String text) {
super(text);
jLabelExtended = this;
mouseMotionAdapter = new MouseMotionAdapter() {
#Override
public void mouseDragged(MouseEvent e) {
System.out.println(e.getX() + " : " + e.getY());
jLabelExtended.setLocation(e.getX(), e.getY()
);
}
};
jLabelExtended.addMouseMotionListener(mouseMotionAdapter);
}
}
This is console part after label dragged:
163 : 163
144 : -87
163 : 162
144 : -88
163 : 161
144 : -89
I have several questions:
Why e.getY() takes negative results?
When I drag my label there are appeares copy of label which drags near my label. How can I fix it?
When I drag my label, it drags very slowly.For example: when I move my cursor on 10 points my label moves only on 5 point. How can I fix it?
Thanks in advance
Here are else one way to extend JLabel:
public class LabelEasy extends JLabel {
private MouseAdapter moveMouseAdapter;
private MouseMotionAdapter mouseMotionAdapter;
private LabelEasy jLabelExtended;
private int xAdjustment, yAdjustment;
Boolean count = false;
public LabelEasy(String text) {
super(text);
jLabelExtended = this;
moveMouseAdapter = new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
if (e.getButton() == 1) {
xAdjustment = e.getX();
yAdjustment = e.getY();
}
}
};
mouseMotionAdapter = new MouseMotionAdapter() {
#Override
public void mouseDragged(MouseEvent e) {
if (count) {
System.out.println(e.getX() + " : " + e.getY());
jLabelExtended.setLocation(xAdjustment + e.getX(), yAdjustment + e.getY());
count = false;
} else {
count = true;
}
;
}
};
jLabelExtended.addMouseMotionListener(mouseMotionAdapter);
jLabelExtended.addMouseListener(moveMouseAdapter);
}
}
But it works like previous variant.

I think you're doing it wrong. The MouseMotionListener is added to the JLabel and its location is relative to the JLabel, not the Container which holds the JLabel, so the information is useless to help you drag it. You may wish to use a MouseAdapter and add it both as a MouseListener and a MouseMotionListener. On mousePressed, get the location of the JLabel and the mouse relative to the screen and then use that for your dragging on mouseDragged. Myself, I wouldn't extend JLabel to do this but would rather just use a regular JLabel, but that's my preference.
Edit: it worked better for me when I dealt with the mouse's position relative to the screen (by calling getLocationOnScreen) and the JLabel's position relative to its Container (by calling getLocation). For e.g.,
import java.awt.*;
import java.awt.event.*;
import java.util.Random;
import javax.swing.*;
public class DragLabelEg {
private static final String[] LABEL_STRINGS = { "Do", "Re", "Me", "Fa",
"So", "La", "Ti" };
private static final int HEIGHT = 400;
private static final int WIDTH = 600;
private static final Dimension MAIN_PANEL_SIZE = new Dimension(WIDTH,
HEIGHT);
private static final int LBL_WIDTH = 60;
private static final int LBL_HEIGHT = 40;
private static final Dimension LABEL_SIZE = new Dimension(LBL_WIDTH,
LBL_HEIGHT);
private JPanel mainPanel = new JPanel();
private Random random = new Random();
public DragLabelEg() {
mainPanel.setPreferredSize(MAIN_PANEL_SIZE);
mainPanel.setLayout(null);
MyMouseAdapter myMouseAdapter = new MyMouseAdapter();
for (int i = 0; i < LABEL_STRINGS.length; i++) {
JLabel label = new JLabel(LABEL_STRINGS[i], SwingConstants.CENTER);
label.setSize(LABEL_SIZE);
label.setOpaque(true);
label.setLocation(random.nextInt(WIDTH - LBL_WIDTH),
random.nextInt(HEIGHT - LBL_HEIGHT));
label.setBackground(new Color(150 + random.nextInt(105),
150 + random.nextInt(105), 150 + random.nextInt(105)));
label.addMouseListener(myMouseAdapter);
label.addMouseMotionListener(myMouseAdapter);
mainPanel.add(label);
}
}
public JComponent getMainPanel() {
return mainPanel;
}
private class MyMouseAdapter extends MouseAdapter {
private Point initLabelLocation = null;
private Point initMouseLocationOnScreen = null;
#Override
public void mousePressed(MouseEvent e) {
JLabel label = (JLabel)e.getSource();
// get label's initial location relative to its container
initLabelLocation = label.getLocation();
// get Mouse's initial location relative to the screen
initMouseLocationOnScreen = e.getLocationOnScreen();
}
#Override
public void mouseReleased(MouseEvent e) {
initLabelLocation = null;
initMouseLocationOnScreen = null;
}
#Override
public void mouseDragged(MouseEvent e) {
// if not dragging a JLabel
if (initLabelLocation == null || initMouseLocationOnScreen == null) {
return;
}
JLabel label = (JLabel)e.getSource();
// get mouse's new location relative to the screen
Point mouseLocation = e.getLocationOnScreen();
// and see how this differs from the initial location.
int deltaX = mouseLocation.x - initMouseLocationOnScreen.x;
int deltaY = mouseLocation.y - initMouseLocationOnScreen.y;
// change label's position by the same difference, the "delta" vector
int labelX = initLabelLocation.x + deltaX;
int labelY = initLabelLocation.y + deltaY;
label.setLocation(labelX, labelY);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createGui();
}
});
}
private static void createGui() {
JFrame frame = new JFrame("App");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new DragLabelEg().getMainPanel());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}

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Java is a programming language and computing platform first released by Sun Microsystems in 1995.

Moving a JLabel Around JPanel - java

I have a JPanel that has 2+ JLables on it, I would like to be able to grab a label then move it to a different location on the JPanel. How can I do that? The only things I can find on this are moving a label from component "A" to component "B", nothing about moving it around on a Panel.

You are probably getting it for the label itself. Try observing the coordinates of the panel. It should work

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