Java JScrollPane Remove Components Without Changing Viewport - java

When there are more than 50 components in my JScrollPane, every time the user decides to go to the next page, the first 10 components in the JScrollPane are cleared.
This functionality works fine and is desirable, but when the components are removed, the viewport/scroll is changed. The view of the scrollpane jumps back each time the components are cleared.
What I'd like is to keep the viewport at exactly the same place, while removing the first components from the JScrollPane.
At the moment I have a workaround, but it's not elegant, and although it finds where the user last was, it's choppy, and jumps the scrollpane which doesn't look right:
if (middlePanel.getComponents().length > 50)
{
Component currentScroll = scrollPane.getViewport().getView();
for (int counter = 0; counter < memeAnchors.size(); counter++)
{
middlePanel.remove(counter);
}
scrollPane.setViewportView(currentScroll);
scrollPane.getVerticalScrollBar().setValue(scrollPane.getVerticalScrollBar().getValue() - 800);
}
Is what I want to do even possible?
Thanks in advance everyone,

OK, I lied about not responding.
One way to do it is as noted below in my SSCCE. Note use of Scrollable. Explanation is in comments:
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.LayoutManager;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
#SuppressWarnings("serial")
public class Sscce extends JPanel {
private static final int INITIAL_ROW_COUNT = 100;
public static final int INCREMENTAL_ADD_ROW_COUNT = 10;
private static final int MIN_VERT_PERCENT = 4;
private static final int TIMER_DELAY = 250;
private ViewportViewPanel viewportViewPanel = new ViewportViewPanel(
new GridLayout(0, 1));
private JScrollPane scrollPane = new JScrollPane(viewportViewPanel);
private BoundedRangeModel vertModel;
private Timer vertChangeTimer;
private int viewportViewPanelIndex = 0;
public Component firstViewedComp;
public Sscce() {
setLayout(new BorderLayout());
add(scrollPane);
for (viewportViewPanelIndex = 0; viewportViewPanelIndex < INITIAL_ROW_COUNT; viewportViewPanelIndex++) {
viewportViewPanel.add(new ViewablePanel(viewportViewPanelIndex));
}
vertModel = scrollPane.getVerticalScrollBar().getModel();
vertModel.addChangeListener(new VertModelChangeListener());
}
private class VertModelChangeListener implements ChangeListener {
#Override
public void stateChanged(ChangeEvent cEvt) {
// if timer is running, get out of here
if (vertChangeTimer != null && vertChangeTimer.isRunning()) {
return;
}
// if haven't set firstViewedComp back to null (done in Timer) get out of here
if (firstViewedComp != null) {
return;
}
// check to see if near bottom
int diff = vertModel.getMaximum() - vertModel.getValue()
- vertModel.getExtent();
int normalizedDiff = (100 * diff) / vertModel.getMaximum();
// if not near bottom, get out of here
if (normalizedDiff >= MIN_VERT_PERCENT) {
return;
}
// create and start timer
vertChangeTimer = new Timer(TIMER_DELAY, new VertChangeTimerListener());
vertChangeTimer.setRepeats(false);
vertChangeTimer.start();
// get viewport and its rectangle
JViewport viewport = scrollPane.getViewport();
Rectangle viewRect = viewport.getViewRect();
// find first component that is inside of viewport's rectangle
Component[] components = viewportViewPanel.getComponents();
for (Component component : components) {
if (viewRect.contains(component.getBounds())) {
if (firstViewedComp == null) {
firstViewedComp = component; // first component found
break;
}
}
}
// delete 10 components at start
// add 10 components add end
for (int i = 0; i < INCREMENTAL_ADD_ROW_COUNT; i++) {
viewportViewPanel.remove(components[i]);
viewportViewPanel.add(new ViewablePanel(viewportViewPanelIndex));
viewportViewPanelIndex++;
}
// redo laying out components and repainting the container
viewportViewPanel.revalidate();
viewportViewPanel.repaint();
// scroll back to first viewed component, but give a little delay to allow
// layout out above to complete. So queue it on the event queue via invokeLater
SwingUtilities.invokeLater(new Runnable() {
public void run() {
viewportViewPanel.scrollRectToVisible(firstViewedComp
.getBounds());
}
});
}
}
// the timer listener. it just nulls out the first viewed component
private class VertChangeTimerListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
firstViewedComp = null;
}
}
private static void createAndShowGui() {
Sscce mainPanel = new Sscce();
JFrame frame = new JFrame("Sscce");
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();
}
});
}
}
// JPanel that is held by the JScrollPane's JViewport and that holds the smaller
// JPanels. Note that it implements Scrollable
#SuppressWarnings("serial")
class ViewportViewPanel extends JPanel implements Scrollable {
private static final int BLOCK = 8;
public ViewportViewPanel(LayoutManager layout) {
super(layout);
}
#Override
public Dimension getPreferredScrollableViewportSize() {
int scrollWidth = ViewablePanel.PREF_W;
int scrollHeight = ViewablePanel.PREF_H * BLOCK;
return new Dimension(scrollWidth, scrollHeight);
}
#Override
public int getScrollableBlockIncrement(Rectangle visibleRectangle,
int orientation, int direction) {
if (orientation == SwingConstants.VERTICAL) {
return ViewablePanel.PREF_H * (3 * BLOCK) / 4;
}
return 0;
}
#Override
public boolean getScrollableTracksViewportHeight() {
return false;
}
#Override
public boolean getScrollableTracksViewportWidth() {
return true;
}
#Override
public int getScrollableUnitIncrement(Rectangle visibleRect,
int orientation, int direction) {
if (orientation == SwingConstants.VERTICAL) {
return ViewablePanel.PREF_H;
}
return 1;
}
}
// small JPanel. Many of these are held in a single GridLayout column
// by the JPanel above.
#SuppressWarnings("serial")
class ViewablePanel extends JPanel {
public static final int PREF_W = 400;
public static final int PREF_H = 50;
private int index;
public ViewablePanel(int index) {
this.setIndex(index);
String title = "index " + index;
setBorder(BorderFactory.createTitledBorder(title));
}
#Override
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
public int getIndex() {
return index;
}
public void setIndex(int index) {
this.index = index;
}
}

Related

Click Event - Accessing a boolean variable from another class [closed]

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Stuck on a problem that requires grabbing a boolean variable from another class.
I have the following for-loop, boolean and if-else statements
import java.awt.*;
import javax.swing.*;
import java.awt.Color.*;
import java.awt.event.MouseListener;
import java.awt.event.MouseEvent;
import java.util.Random;
public class Checkers extends JFrame
{
Random random = new Random();
private final int ROWS = 2;
private final int COLS = 5;
private final int GAP = 2;
private final int NUM = ROWS * COLS;
private int i;
private int score;
private JPanel pane = new JPanel(new GridLayout(ROWS,COLS, GAP,GAP));
private JPanel pane2 = new JPanel();
private JPanel pane3 = new JPanel();
private JButton btn1 = new JButton("Play A Game");
private JButton btn2 = new JButton("Exit");
private JButton btn3 = new JButton("Easy");
private JButton btn4 = new JButton("Intermediate");
private JButton btn5 = new JButton("Difficult");
private JLabel lbl1 = new JLabel ("score: " + score);
private JLabel gameLost = new JLabel("You lose! You got: " + score + " points");
private JButton btnRestart = new JButton("Restart");
private MyPanel [] panel = new MyPanel[NUM];
private Color col1 = Color.RED;
private Color col2 = Color.WHITE;
private Color col3 = Color.GREEN;
private Color tempColor;
private boolean isPanelDisabled;
//Starts the checkers GUI, calling the constructor below this.
public static void main(String[] args){
new Checkers();
}
//Sets the dimensions of the GUI, visibility, background color and
//contents via the setBoard();
public Checkers()
{
super("Checkers");
setSize(600,600);
setVisible(true);
setBackground(Color.BLACK);
setBoard();
}
//Makes the grid, contains a conditional boolean, adds the panels to grid based on i value.
//sets Colours accordingly
public void setBoard()
{
boolean isPanelDisabled = false;
for (int i = 0; i < panel.length; i++) {
panel[i] = new MyPanel(this);
pane.add(panel[i]);
if (i % COLS == 0) {
tempColor = col1;
}
if (i == 9 || i <8) {
panel[i].setBackground(col1);
}
if(i == 8){
isPanelDisabled = true;
panel[i].setBackground(col3);
}
}
//pane background colour and the size of this pane.
pane.setBackground(Color.BLACK);
pane.setPreferredSize(new Dimension(300,300));
//pane background colour and size of this pane.
pane2.setBackground(Color.white);
pane2.setPreferredSize(new Dimension(300,300));
//directions on the board where these panes appear.
add(pane, BorderLayout.WEST);
add(pane2, BorderLayout.EAST);
pane2.add(lbl1);
pane2.add(btnRestart);
btnRestart.addActionListener( e -> restartBoard());
pane2.setLayout(new BoxLayout(pane2, BoxLayout.PAGE_AXIS));
}
//increments the score for the user based on current points.
public void incrementScore(){
if (score != 5){
score++;
lbl1.setText("Score: " + Integer.toString(score));
}
else if(score == 5){
lbl1.setText("Congratulations!, you've won!, your score is:" + score);
}
}
}
and this mouseClicked Event
import java.awt.Color;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.*;
import java.awt.event.*;
import javax.swing.JPanel;
public class MyPanel extends JPanel implements MouseListener, ActionListener {
private final Checkers checkers;
private boolean isPanelDisabled;
//MyPanel Constructor that initiates a instance of checkers.
public MyPanel(Checkers checkers) {
this.checkers = checkers;
addMouseListener(this);
}
#Override
public void actionPerformed(ActionEvent e){
}
// Sets the panel colours according to their int number and the boolean condiiton.
#Override
public void mouseClicked(MouseEvent e) {
if (isPanelDisabled == true){
setBackground(Color.CYAN);
}
else{
setBackground(Color.BLACK);
checkers.incrementScore();
}
}
My Expected result of this should be that if the user clicks the 8th panel in that grid, then the color of that panel will be cyan when pressed and not black, but it cant access the boolean variable? where am i going wrong here?
Your question involves communication between objects of different classes, and there are several ways to do this, but most basic is to call a method of an object in one class to the other.
First lets set up the problem,... I've created classes called MyPanel2 and Checkers2, to distinguish them from yours.
Say in MyPanel2 we have a Checkers2 field and a boolean field called selected that is set to false:
private Checkers2 checkers;
private boolean selected = false;
along with appropriate boolean getter and setter:
public void setSelected(boolean selected) {
this.selected = selected;
}
public boolean isSelected() {
return selected;
}
And say within the Checkers2 class you have a 10 instances of MyPanel2 held within an array, and you want the user to be able to "select" instances of the class, but only allow 7 of them to be selected, and assume that you want to user the set up that you're currently using, you could give the main class, a method, public boolean isPanelDisabled(), and have the MyPanel2 class call this method to determine if selection is allowed. So within MyPanel2 you could have a MouseListener with something like:
#Override
public void mousePressed(MouseEvent e) {
if (selected) {
return;
}
// call the Checkers2 boolean method to check
if (checkers.isPanelDisabled()) {
setBackground(DISABLED_COLOR);
} else {
setBackground(SELECTED_COLOR);
setSelected(true);
}
}
Within Checkers2 .isPanelDisabled() method you'd iterate through the array of MyPanel2 instances to see how many have been selected, something like this could work:
public boolean isPanelDisabled() {
int count = 0;
for (MyPanel2 panel2 : myPanels) {
if (panel2.isSelected()) {
count++;
}
}
return count >= MAX_COUNT;
}
The whole MCVE testable code could look like:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Checkers2 extends JFrame {
private static final int MAX_COUNT = 7;
private final int ROWS = 2;
private final int COLS = 5;
private final int GAP = 2;
private final int NUM = ROWS * COLS;
private MyPanel2[] myPanels = new MyPanel2[NUM];
public Checkers2() {
super("Checkers");
setDefaultCloseOperation(EXIT_ON_CLOSE);
JPanel gridPanel = new JPanel(new GridLayout(ROWS, COLS, 1, 1));
gridPanel.setBackground(Color.BLACK);
gridPanel.setBorder(BorderFactory.createLineBorder(Color.BLACK));
for (int i = 0; i < myPanels.length; i++) {
MyPanel2 myPanel = new MyPanel2(this);
gridPanel.add(myPanel);
myPanels[i] = myPanel;
}
JButton resetButton = new JButton("Reset");
resetButton.setMnemonic(KeyEvent.VK_R);
resetButton.addActionListener(evt -> {
for (MyPanel2 myPanel2 : myPanels) {
myPanel2.reset();
}
});
JButton exitButton = new JButton("Exit");
exitButton.setMnemonic(KeyEvent.VK_X);
exitButton.addActionListener(evt -> System.exit(0));
JPanel buttonPanel = new JPanel();
buttonPanel.add(resetButton);
add(gridPanel);
add(buttonPanel, BorderLayout.PAGE_END);
pack();
setLocationRelativeTo(null);
}
public boolean isPanelDisabled() {
int count = 0;
for (MyPanel2 panel2 : myPanels) {
if (panel2.isSelected()) {
count++;
}
}
return count >= MAX_COUNT;
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
new Checkers2().setVisible(true);
});
}
}
class MyPanel2 extends JPanel {
private static final int PREF_W = 200;
private static final int PREF_H = PREF_W;
private static final int GR = 240;
public static final Color BASE_COLOR = new Color(GR, GR, GR);
public static final Color DISABLED_COLOR = Color.CYAN;
public static final Color SELECTED_COLOR = Color.BLACK;
private Checkers2 checkers;
private boolean selected = false;
public MyPanel2(Checkers2 checkers) {
setBackground(BASE_COLOR);
this.checkers = checkers;
setPreferredSize(new Dimension(PREF_W, PREF_H));
addMouseListener(new MyMouse());
}
public void setSelected(boolean selected) {
this.selected = selected;
}
public boolean isSelected() {
return selected;
}
public void reset() {
setBackground(BASE_COLOR);
setSelected(false);
}
private class MyMouse extends MouseAdapter {
#Override
public void mousePressed(MouseEvent e) {
if (selected) {
return;
}
if (checkers.isPanelDisabled()) {
setBackground(DISABLED_COLOR);
} else {
setBackground(SELECTED_COLOR);
setSelected(true);
}
}
}
}
Another Option is to take all the logic out of MyPanel and put it into the main program, something like:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
#SuppressWarnings("serial")
public class Checkers3 extends JPanel {
private static final int MAX_COUNT = 7;
private final int ROWS = 2;
private final int COLS = 5;
private final int GAP = 2;
private final int NUM = ROWS * COLS;
private MyPanel3[] myPanels = new MyPanel3[NUM];
public Checkers3() {
JPanel gridPanel = new JPanel(new GridLayout(ROWS, COLS, 1, 1));
gridPanel.setBackground(Color.BLACK);
gridPanel.setBorder(BorderFactory.createLineBorder(Color.BLACK));
MyMouse myMouse = new MyMouse();
for (int i = 0; i < myPanels.length; i++) {
MyPanel3 myPanel = new MyPanel3();
myPanel.addMouseListener(myMouse);
gridPanel.add(myPanel);
myPanels[i] = myPanel;
}
JButton resetButton = new JButton("Reset");
resetButton.setMnemonic(KeyEvent.VK_R);
resetButton.addActionListener(evt -> {
for (MyPanel3 myPanel : myPanels) {
myPanel.reset();
}
});
JButton exitButton = new JButton("Exit");
exitButton.setMnemonic(KeyEvent.VK_X);
exitButton.addActionListener(evt -> System.exit(0));
JPanel buttonPanel = new JPanel();
buttonPanel.add(resetButton);
setLayout(new BorderLayout());
add(gridPanel);
add(buttonPanel, BorderLayout.PAGE_END);
}
public boolean isPanelDisabled() {
int count = 0;
for (MyPanel3 panel : myPanels) {
if (panel.isSelected()) {
count++;
}
}
return count >= MAX_COUNT;
}
private class MyMouse extends MouseAdapter {
#Override
public void mousePressed(MouseEvent e) {
MyPanel3 myPanel = (MyPanel3) e.getSource();
if (myPanel.isSelected()) {
return; // it's already selected
} else if (isPanelDisabled()) {
myPanel.setSelected(false);
} else {
myPanel.setSelected(true);
}
}
}
private static void createAndShowGui() {
Checkers3 mainPanel = new Checkers3();
JFrame frame = new JFrame("Checkers");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}
#SuppressWarnings("serial")
class MyPanel3 extends JPanel {
private static final int PREF_W = 200;
private static final int PREF_H = PREF_W;
private static final int GR = 240;
public static final Color BASE_COLOR = new Color(GR, GR, GR);
public static final Color DISABLED_COLOR = Color.CYAN;
public static final Color SELECTED_COLOR = Color.BLACK;
private boolean selected = false;
public MyPanel3() {
setBackground(BASE_COLOR);
setPreferredSize(new Dimension(PREF_W, PREF_H));
}
public void setSelected(boolean selected) {
this.selected = selected;
Color background = selected ? SELECTED_COLOR : DISABLED_COLOR;
setBackground(background);
}
public boolean isSelected() {
return selected;
}
public void reset() {
setSelected(false);
setBackground(BASE_COLOR);
}
}
But the BEST option is to put all logic within a separate model class (or classes) and make the GUI's as dumb as possible.

Why do the panels disappear when i press UP?

This is my code for a game im making. At the moment im not worried about how the game functions I've been more so worried about the fact that each time I hit the UP button the panels disappear and sometimes when i hit the LEFT button as well. Is there an explanation to this can anyone help me understand why this happens?? I have a feeling it has something to do with my if statements but im not really sure. also, im messing around with the key listener and if you could give me some advice on key listeners like some dos and donts I really appreciate the help!!
import javax.swing.*;
import java.applet.*;
import java.awt.event.*;
import java.awt.*;
public class Game extends Applet implements ActionListener,KeyListener {
Image image;
MediaTracker tr;
JLabel label,computerLabel;
JPanel panel,computerPanel;
Button start,up,down;
Label result;
Dimension SIZE = new Dimension(50,50);
int x = 0;
int y = 0;
int w = 100;
int q = 100;
int WIDTH = 50;
int HEIGHT = 50;
//Player Integers
int zeroPosX,zeroPosY,xLeft,xUp;
//Computer integers
int compZeroPosX,compZeroPosY,compXLeft,compXUp;
//--------------------------------------
public void init() {
setLayout(new FlowLayout());
start = new Button("Start");
up = new Button("UP");
down = new Button("LEFT");
//PlayerPiece stuff
ImageIcon icon = new ImageIcon("playerpiece.png");
label = new JLabel(icon);
panel = new JPanel();
label.setVisible(true);
panel.add(label);
panel.setPreferredSize(SIZE);
//ComputerPiece Stuff
ImageIcon computerIcon = new ImageIcon("computerPiece.png");
computerPanel = new JPanel();
computerLabel = new JLabel(computerIcon);
computerLabel.setVisible(true);
computerPanel.add(computerLabel);
computerPanel.setPreferredSize(SIZE);
//===============================================
result = new Label("=========");
addKeyListener(this);
setSize(650,650);
up.addActionListener(this);
down.addActionListener(this);
start.addActionListener(this);
label.setSize(WIDTH,HEIGHT);
label.setLocation(0,0);
add(computerPanel);
add(panel);
add(start);
add(up);
add(down);
add(result);
}
//--------------------------------------
public void paint(Graphics g) {
Graphics2D firstLayer = (Graphics2D)g;
Graphics2D secondLayer = (Graphics2D)g;
Graphics2D thirdLayer = (Graphics2D)g;
secondLayer.setColor(Color.BLACK);
for(x=100; x<=500; x+=100)
for(y=100; y <=500; y+=100)
{
firstLayer.fillRect(x,y,WIDTH,HEIGHT);
}
for(w=150; w<=500; w+=100)
for(q=150; q <=500; q+=100)
{
secondLayer.fillRect(w,q,WIDTH,HEIGHT);
}
}
//--------------------------------------
public void actionPerformed(ActionEvent ae) {
int [] range = {50,0,0,0,0};
int selection = (int)Math.random()*5 ;
//~~~~~~~~~~~~~~~~~~~~~~~~~
//PlayerPositioning
zeroPosX = panel.getX();
zeroPosY = panel.getY();
xLeft = zeroPosX - 50;
xUp = zeroPosY - 50;
//ComputerPositioning
compZeroPosX = computerPanel.getX();
compZeroPosY = computerPanel.getY();
compXLeft = compZeroPosX - range[selection];
compXUp = compZeroPosY - range[selection];
//~~~~~~~~~~~~~~~~~~~~~~~~~~
Button user = (Button)ae.getSource();
//Starting the game
if(user.getLabel() == "Start") {
result.setText("=========");
//playersetup
label.setLocation(0,0);
panel.setLocation(300,500);
//============================
//npc setup
computerLabel.setLocation(0,0);
computerPanel.setLocation(500,300);
}
if(compZeroPosX >= 150) {
if(compZeroPosY >= 150) {
if(zeroPosX >= 150) {
if(zeroPosY >=150) {
if(user.getLabel() == "UP") {
panel.setLocation(zeroPosX,xUp);
}
else
computerPanel.setLocation(compZeroPosX,compXUp);
if(user.getLabel() == "LEFT") {
panel.setLocation(xLeft,zeroPosY);
}
else
computerPanel.setLocation(compXLeft,compZeroPosY);
if(panel.getX() < 150)
result.setText("GAME-OVER");
if(panel.getY() < 150)
result.setText("GAME-OVER");
}
}
}
}
}
#Override
public void keyPressed(KeyEvent kp) {
int keycode = kp.getKeyCode();
switch (keycode) {
case KeyEvent.VK_W:
panel.setLocation(xLeft,zeroPosY);
break;
}
}
#Override
public void keyReleased(KeyEvent kr) {
}
#Override
public void keyTyped(KeyEvent kt) {
}
}
Issues and suggestions:
You're mixing AWT (e.g., Applet, Button, Label) with Swing (e.g., JPanel, JLabel) dangerously and without need. Stick with Swing and get rid of all vestiges of AWT.
You're painting directly in a top-level window, here the Applet, a dangerous thing to do. Don't. Follow the Swing graphics tutorials and do your drawing in a JPanel's paintComponent method.
You're not calling the super method within your painting method override, another dangerous thing to do, and another indication that you're trying to do this without reading the important relevant tutorials.
Don't compare Strings using == or !=. Use the equals(...) or the equalsIgnoreCase(...) method instead. Understand that == checks if the two object references are the same which is not what you're interested in. The methods on the other hand check if the two Strings have the same characters in the same order, and that's what matters here.
You're trying to directly set the location of a component such as a JPanel without regard for the layout managers. Don't do this. Instead move logical (non-component) entities and display the movement in your graphics.
You can find links to the Swing tutorials and to other Swing resources here: Swing Info
Later we can talk why you should avoid applets of all flavors...
Myself, I'd move ImageIcons around a grid of JLabels and not directly use a painting method at all. For example,
To see, run the following code:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import javax.imageio.ImageIO;
import javax.swing.*;
#SuppressWarnings("serial")
public class Game2 extends JPanel {
private static final String CPU_PATH = "https://upload.wikimedia.org/wikipedia/commons/thumb/4/4f/"
+ "Gorilla-thinclient.svg/50px-Gorilla-thinclient.svg.png";
private static final String PERSON_PATH = "https://upload.wikimedia.org/wikipedia/commons/thumb/d/d8/"
+ "Emblem-person-blue.svg/50px-Emblem-person-blue.svg.png";
private static final int SQR_WIDTH = 50;
private static final int SIDES = 10;
private static final Dimension SQR_SIZE = new Dimension(SQR_WIDTH, SQR_WIDTH);
private static final Color DARK = new Color(149, 69, 53);
private static final Color LIGHT = new Color(240, 220, 130);
private JLabel[][] labelGrid = new JLabel[SIDES][SIDES];
private Icon playerIcon;
private Icon computerIcon;
public Game2() throws IOException {
// would use images instead
playerIcon = createIcon(PERSON_PATH);
computerIcon = createIcon(CPU_PATH);
JPanel buttonPanel = new JPanel();
buttonPanel.add(new JButton(new StartAction("Start", KeyEvent.VK_S)));
buttonPanel.add(new JButton(new UpAction("Up", KeyEvent.VK_U)));
buttonPanel.add(new JButton(new LeftAction("Left", KeyEvent.VK_L)));
JPanel gameBrd = new JPanel(new GridLayout(SIDES, SIDES));
gameBrd.setBorder(BorderFactory.createLineBorder(Color.BLACK));
for (int i = 0; i < labelGrid.length; i++) {
for (int j = 0; j < labelGrid[i].length; j++) {
JLabel label = new JLabel();
label.setPreferredSize(SQR_SIZE);
label.setOpaque(true);
Color c = i % 2 == j % 2 ? DARK : LIGHT;
label.setBackground(c);
gameBrd.add(label);
labelGrid[i][j] = label;
}
}
setLayout(new BorderLayout());
add(buttonPanel, BorderLayout.PAGE_START);
add(gameBrd);
// random placement, just for example
labelGrid[4][4].setIcon(computerIcon);
labelGrid[5][5].setIcon(playerIcon);
}
private Icon createIcon(String path) throws IOException {
URL url = new URL(path);
BufferedImage img = ImageIO.read(url);
return new ImageIcon(img);
}
private abstract class MyAction extends AbstractAction {
public MyAction(String name, int mnemonic) {
super(name);
putValue(MNEMONIC_KEY, mnemonic);
}
}
private class StartAction extends MyAction {
public StartAction(String name, int mnemonic) {
super(name, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
// TODO start game code
}
}
// move all icons up
private class UpAction extends MyAction {
public UpAction(String name, int mnemonic) {
super(name, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
// collection to hold label that needs to be moved
Map<JLabel, Icon> labelMap = new HashMap<>();
for (int i = 0; i < labelGrid.length; i++) {
for (int j = 0; j < labelGrid[i].length; j++) {
Icon icon = labelGrid[i][j].getIcon();
if (icon != null) {
int newI = i == 0 ? labelGrid.length - 1 : i - 1;
labelGrid[i][j].setIcon(null);
labelMap.put(labelGrid[newI][j], icon);
}
}
}
// move the icon after the iteration complete so as not to move it twice
for (JLabel label : labelMap.keySet()) {
label.setIcon(labelMap.get(label));
}
}
}
// move all icons left
private class LeftAction extends MyAction {
public LeftAction(String name, int mnemonic) {
super(name, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
Map<JLabel, Icon> labelMap = new HashMap<>();
for (int i = 0; i < labelGrid.length; i++) {
for (int j = 0; j < labelGrid[i].length; j++) {
Icon icon = labelGrid[i][j].getIcon();
if (icon != null) {
int newJ = j == 0 ? labelGrid[i].length - 1 : j - 1;
labelGrid[i][j].setIcon(null);
labelMap.put(labelGrid[i][newJ], icon);
}
}
}
for (JLabel label : labelMap.keySet()) {
label.setIcon(labelMap.get(label));
}
}
}
private static void createAndShowGui() {
Game2 mainPanel = null;
try {
mainPanel = new Game2();
} catch (IOException e) {
e.printStackTrace();
System.exit(-1);
}
JFrame frame = new JFrame("Game2");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
createAndShowGui();
});
}
}

How to make two thread communicate through handler?

I have form that button can auto re-size their size when mouse hover on button and default their size when mouse is exited. It work normally first time but after i try it more than one time their size is enlarged that i can not control normally.
ImageIcon ima=new ImageIcon("C:\\Users\\chen rina\\Pictures\\win.png");
ImageIcon icon;
Thread thr;
Runnable r=new Runnable() {
#Override
public void run() {
int i=40;
while(i!=80){
try{
Thread.sleep(20);
Image scale=ima.getImage().getScaledInstance(i,i,Image.SCALE_FAST);
icon=new ImageIcon(scale);
btn2.setIcon(icon);
i=i+5;
}
catch(Exception ex){}
}
}
};
private void btn2MouseEntered(java.awt.event.MouseEvent evt) {
// TODO add your handling code here:
thr=new Thread(r);
thr.start();
}
Runnable res=new Runnable() {
int i;
#Override
public void run() {
int i=80;
while(i!=40){
try{
Thread.sleep(20);
Image scale=ima.getImage().getScaledInstance(i,i,Image.SCALE_AREA_AVERAGING);
icon=new ImageIcon(scale);
btn2.setIcon(icon);
i=i-5;
}
catch(Exception ex){}
}
}
};
private void btn2MouseExited(java.awt.event.MouseEvent evt) {
thr=new Thread(res);
thr.start();
}
Your code violates Swing thread integrity rules by making Swing calls, here setIcon(...) from within a background state. Having said that, why not simplify all of this by:
Reading in and creating and storing your ImageIcons once and only once
Never ignore exceptions as you're doing. That's unsafe coding.
Most important, use a Swing Timer to simply swap icons every 20 msec, and have no fear about violating Swing threading rules.
Your grow Timer's ActionListener could be as simple as this:
// a private inner class
private class GrowListener implements ActionListener {
private int index = 0;
#Override
public void actionPerformed(ActionEvent e) {
// assuming the button is called button and the list iconList
button.setIcon(iconList.get(index));
index++;
if (index >= iconList.size()) {
((Timer) e.getSource()).stop();
}
}
}
The iconList would look something like:
private List<Icon> iconList = new ArrayList<>();
And you could fill it with code looking something like:
for (int i = startLength; i <= endLength; i += step) {
Image img = originalImg.getScaledInstance(i, i, Image.SCALE_FAST);
iconList.add(new ImageIcon(img));
}
And a more complete and runnable example:
import java.awt.Dimension;
import java.awt.Image;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import javax.imageio.ImageIO;
import javax.swing.*;
#SuppressWarnings("serial")
public class ResizeIconTest extends JPanel {
private static final int PREF_W = 400;
private static final int PREF_H = PREF_W;
private static final int START_LENGTH = 40;
private static final int END_LENGTH = 120;
private static final int STEP = 5;
private static final int TIMER_DELAY = 20;
private static final String URL_SPEC = "https://upload.wikimedia.org/wikipedia/commons/"
+ "thumb/2/2b/Oryx_gazella_-_Etosha_2014_square_crop.jpg/"
+ "600px-Oryx_gazella_-_Etosha_2014_square_crop.jpg";
private JButton button = new JButton();
private ResizeIcon resizeIcon;
public ResizeIconTest() throws IOException {
add(button);
URL imageUrl = new URL(URL_SPEC);
BufferedImage originalImg = ImageIO.read(imageUrl);
resizeIcon = new ResizeIcon(button, originalImg, START_LENGTH,
END_LENGTH, STEP, TIMER_DELAY);
button.setIcon(resizeIcon.getSmallestIcon());
button.addMouseListener(new MouseAdapter() {
#Override
public void mouseEntered(MouseEvent e) {
resizeIcon.grow();
}
#Override
public void mouseExited(MouseEvent e) {
resizeIcon.shrink();
}
});
}
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
private static void createAndShowGui() {
ResizeIconTest mainPanel = null;
try {
mainPanel = new ResizeIconTest();
} catch (IOException e) {
e.printStackTrace();
System.exit(-1);
}
JFrame frame = new JFrame("ResizeIconTest");
frame.setDefaultCloseOperation(JFrame.DISPOSE_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 ResizeIcon {
private List<Icon> iconList = new ArrayList<>();
private AbstractButton button;
private int delayTime;
private Timer growTimer;
private Timer shrinkTimer;
public ResizeIcon(AbstractButton button, BufferedImage originalImg,
int startLength, int endLength, int step, int delayTime) {
this.button = button;
this.delayTime = delayTime;
for (int i = startLength; i <= endLength; i += step) {
Image img = originalImg.getScaledInstance(i, i, Image.SCALE_FAST);
iconList.add(new ImageIcon(img));
}
}
public Icon getSmallestIcon() {
return iconList.get(0);
}
public void grow() {
if (growTimer != null && growTimer.isRunning()) {
return; // let's not run this multiple times
}
if (button.getIcon() == iconList.get(iconList.size() - 1)) {
return; // don't run if already at largest size
}
growTimer = new Timer(delayTime, new GrowListener());
growTimer.start();
}
public void shrink() {
if (shrinkTimer != null && shrinkTimer.isRunning()) {
return; // let's not run this multiple times
}
if (button.getIcon() == iconList.get(0)) {
return; // don't run if already at smallest size
}
shrinkTimer = new Timer(delayTime, new ShrinkListener());
shrinkTimer.start();
}
private class GrowListener implements ActionListener {
private int index = 0;
#Override
public void actionPerformed(ActionEvent e) {
button.setIcon(iconList.get(index));
index++;
if (index >= iconList.size()) {
((Timer) e.getSource()).stop();
}
}
}
private class ShrinkListener implements ActionListener {
private int index = iconList.size() - 1;
#Override
public void actionPerformed(ActionEvent e) {
button.setIcon(iconList.get(index));
index--;
if (index < 0) {
((Timer) e.getSource()).stop();
}
}
}
}

Java - adding JButton array to JFrame

I am trying to add a 2D JButton array to a JFrame, I don't get any errors, just the JButtons don't show up.
Creating the JButtons:
public class TTTGrid {
private static JFrame frame;
private static int[][] coords;
private static int width, height;
public TTTGrid(JFrame frame,int[][] coords, int width, int height){
this.frame = frame;
this.coords = coords;
this.width = width;
this.height = height;
}
static JButton map[][] = new JButton[3][3];
public void Draw(){
for(int i = 0; i<coords.length; i++){
for(int j = 0; j<coords[i].length; j++){
map[i][j] = new JButton();
map[i][j].setBounds(i*100, j*100, width, height);
frame.add(map[i][j]);
}
}
}
}
Where the draw method is called:
public class TTTthread extends TTT implements Runnable {
int[][] map = new int[3][3];
TTTGrid grid = new TTTGrid(frame, map, 100, 100);
#Override
public void run() {
try {
while (true) {
grid.Draw();
Thread.sleep(20);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
If your code is running like I think it's running, you appear to be trying to add 9 JButtons to your GUI 50 times a second! That's a heck of a lot of buttons -- are you sure that this is what you want to be doing? Your code also runs far afoul of Swing threading rules by making Swing calls (a lot of Swing calls!) off of the Swing event thread.
Your main solution is likely to
Add your 9 JButtons to a JPanel that uses a GridLayout(3, 3)
Do this only once not 50 times a second
Then add that JPanel to your GUI, BorderLayout.CENTER and to be sure not to use null layouts.
Not try to set the bounds, size or locations of these JButtons, but rather to let the layout managers to the work
Get rid of that while loop and instead change your code to be more event-driven using Swing's event driven model.
Strive to use mostly non-static variables and methods so that your classes become true OOPS-compliant classes, allowing them to take advantage of the benefits of OOPS programming, including reducing program complexity and interconnectedness (reduce coupling).
For example
import java.awt.Color;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.*;
import javax.swing.*;
public class MyTttFoo extends JPanel {
// it's OK for constants to be static
private static final long serialVersionUID = 1L;
private static final int ROWS = 3;
// use a larger Font to make buttons larger
private static final Font BTN_FONT = new Font(Font.SANS_SERIF, Font.BOLD, 60);
private static final String BLANK = " ";
private static final String X = "X";
private static final String O = "O";
// but not most variables
private JButton[][] buttonGrid = new JButton[ROWS][ROWS];
public MyTttFoo() {
setBackground(Color.black);
// use layout managers to help you create your GUI
setLayout(new GridLayout(ROWS, ROWS, 1, 1));
ActionListener btnListener = new ButtonListener();
// create your buttons and add them only **once**
for (int row = 0; row < buttonGrid.length; row++) {
for (int col = 0; col < buttonGrid[row].length; col++) {
JButton button = new JButton(BLANK);
button.setFont(BTN_FONT);
button.addActionListener(btnListener);
add(button); // add button to a gridlayout using component
buttonGrid[row][col] = button; // and assign into the array
}
}
}
private class ButtonListener implements ActionListener {
private boolean xTurn = true;
#Override
public void actionPerformed(ActionEvent e) {
AbstractButton btn = (AbstractButton) e.getSource();
String txt = btn.getText();
if (txt.equals(BLANK)) {
if (xTurn) {
btn.setText(X);
} else {
btn.setText(O);
}
xTurn = !xTurn;
}
}
}
private static void createAndShowGui() {
MyTttFoo mainPanel = new MyTttFoo();
JFrame frame = new JFrame("MyTttFoo");
frame.setDefaultCloseOperation(JFrame.DISPOSE_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();
}
});
}
}

Toggle read-only in Java

Is there a way to toggle a read-only mode so when you click any object in your window it simply returns what you clicked, ignoring the object's usual event handling? IE, while in this "read-only" mode, if you click on a Button, it simply returns the button, not actually pressing the button. Then I could do something like:
if ("thing pressed" == button) "do this";
else if ("thing pressed" == panel) "do that";
else "do nothing";
Here's my code, its a frame with 3 colored boxes. Clicking the 2nd box, the 3rd box, or the background will display a message. Clicking box 1 does nothing. I like using new mouse adapters so I want to do it this way.
Now what I want is when you click box 1, box 1 is treated as selected (if that helps you get the picture). Then if you click anywhere, including box 1 again, box 1 is deselected and nothing else (meaning that box 2, box 3. or the background's message will display). At that time, only if box 2 or 3 were clicked, they will still not display their normal message but a different message would be displayed.
I'm very sorry if I come off a little short.
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Labels {
public static void main(String[] args) {
new Labels();
}
Square l1, l2, l3;
public Labels() {
JFrame frame = new JFrame();
JPanel panel = new JPanel();
l1 = new Square();
l2 = new Square();
l3 = new Square();
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(120, 150);
frame.setResizable(false);
panel.setVisible(true);
panel.setLayout(null);
l1.setLocation(5, 5);
l2.setLocation(5, 60);
l3.setLocation(60, 5);
l2.setColor("yellow");
l3.setColor("black");
l1.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
//do nothing
}
});
l2.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
System.out.println("Pushed label 2");
}
});
l3.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
System.out.println("Pushed label 3");
}
});
panel.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
System.out.println("pushed background");
}
});
frame.add(panel);
panel.add(l1);
panel.add(l2);
panel.add(l3);
}
class Square extends JLabel{
Color color = Color.blue;
public Square() {
// TODO Auto-generated constructor stub\
setVisible(true);
setSize(50,50);
}
public void paint(Graphics g) {
super.paint(g);
g.setColor(color);
g.fillRect(0, 0, 50, 50);
}
public void setColor(String color){
if (color == "white") this.color = Color.white;
else if (color == "black") this.color = Color.black;
else if (color == "yellow") this.color = Color.yellow;
else {
System.out.println("Invalid color");
return;
}
repaint();
}
}
}
Don't disable anything. Simply change the state of your class, perhaps by using a few boolean flag variables/fields and change these flags depending on what is pressed.
So have boolean fields called label1PressedLast, label2PressedLast, and label3PressedLast or something similar, and when a label is pressed, check the states of all other flags and have your program's behavior change depending on the state of these flags and the label that was just pressed. Then set all flags to false except for the one corresponding to the label that was just pressed.
For example, this little program reacts only if the first and then the third JLabel have been pressed:
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.*;
public class FlagEg extends JPanel {
private static final int LABEL_COUNT = 3;
private JLabel[] labels = new JLabel[LABEL_COUNT];
private boolean[] flags = new boolean[LABEL_COUNT];
public FlagEg() {
setLayout(new GridLayout(1, 0, 20, 0));
setBorder(BorderFactory.createEmptyBorder(15, 15, 15, 15));
// panel mouse listener
addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent arg0) {
inactivateAll();
}
});
MouseListener labelsMouseListener = new MouseAdapter() {
#Override
public void mousePressed(MouseEvent mouseEvt) {
myMousePressed(mouseEvt);
}
};
// create JLabels and add MouseListener
for (int i = 0; i < labels.length; i++) {
labels[i] = new JLabel("Label " + (i + 1));
labels[i].addMouseListener(labelsMouseListener);
labels[i].setOpaque(true);
labels[i].setBorder(BorderFactory.createLineBorder(Color.black));
add(labels[i]);
}
}
private void inactivateAll() {
for (int i = 0; i < labels.length; i++) {
labels[i].setBackground(null);
flags[i] = false;
}
}
private void myMousePressed(MouseEvent mouseEvt) {
JLabel label = (JLabel) mouseEvt.getSource();
// which label was pressed?
int index = -1;
for (int i = 0; i < labels.length; i++) {
if (label == labels[i]) {
index = i;
}
}
// check if first label and then third pressed:
if (flags[0] && index == 2) {
System.out.println("first and then third label pressed!");
}
// reset all labels and flags to initial state
inactivateAll();
// set pressed label background color and set flag of label just pressed
labels[index].setBackground(Color.pink);
flags[index] = true;
}
private static void createAndShowGui() {
FlagEg mainPanel = new FlagEg();
JFrame frame = new JFrame("Flag Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
Logic iteration two: only label 1 is the "primer" JLabel. This is actually easier to implement, because now you only need one boolean flag, that representing label 1 being pressed:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
#SuppressWarnings("serial")
public class FlagEg2 extends JPanel {
private static final int LABEL_COUNT = 3;
private JLabel[] labels = new JLabel[LABEL_COUNT];
private boolean label1Flag = false;
public FlagEg2() {
setLayout(new GridLayout(1, 0, 20, 0));
setBorder(BorderFactory.createEmptyBorder(15, 15, 15, 15));
// panel mouse listener
addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent arg0) {
inactivateAll();
}
});
MouseListener labelsMouseListener = new MouseAdapter() {
#Override
public void mousePressed(MouseEvent mouseEvt) {
myMousePressed(mouseEvt);
}
};
// create JLabels and add MouseListener
for (int i = 0; i < labels.length; i++) {
labels[i] = new JLabel("Label " + (i + 1));
labels[i].addMouseListener(labelsMouseListener);
labels[i].setOpaque(true);
labels[i].setBorder(BorderFactory.createLineBorder(Color.black));
add(labels[i]);
}
}
private void inactivateAll() {
for (int i = 0; i < labels.length; i++) {
labels[i].setBackground(null);
label1Flag = false;
}
}
private void myMousePressed(MouseEvent mouseEvt) {
JLabel label = (JLabel) mouseEvt.getSource();
// which label was pressed?
int index = -1;
for (int i = 0; i < labels.length; i++) {
if (label == labels[i]) {
index = i;
}
}
if (label1Flag) {
if (index == 1) {
System.out.println("Label 1 and label 2 pressed");
} else if (index == 2) {
System.out.println("Label 1 and label 3 pressed");
}
}
// reset all labels and flags to initial state
inactivateAll();
// if label1, then activate it
if (index == 0) {
labels[0].setBackground(Color.pink);
label1Flag = true;
}
}
private static void createAndShowGui() {
FlagEg2 mainPanel = new FlagEg2();
JFrame frame = new JFrame("Flag Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
package javaapplication6;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
/**
*
* #author Jan Vorcak <vorcak#mail.muni.cz>
*/
public class Main {
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
MouseListener listener = new MouseAdapter() {
private int count = 0;
#Override
public void mouseClicked(MouseEvent e) {
if(e.getComponent() instanceof JLabel) {
count++;
if (count >= 2) {
System.out.println("clicked 2 times on labels");
count = 0;
}
} else {
count = 0;
}
}
};
JFrame frame = new JFrame();
JPanel panel = new JPanel();
JLabel l1 = new JLabel("Label 1");
JLabel l2 = new JLabel("Label 2");
JLabel l3 = new JLabel("Label 3");
l1.addMouseListener(listener);
l2.addMouseListener(listener);
l3.addMouseListener(listener);
frame.addMouseListener(listener); // or panel.addMouseListener(listener);
panel.add(l1);
panel.add(l2);
panel.add(l3);
frame.add(panel);
frame.pack();
frame.setVisible(true);
}
}
You could want to create a listener that do the job for using the putClientProperty method of JComponent.
public class JComponentClickCountListener extends MouseAdapter {
private final Integer ONE = 1;
#Override
public void mouseClicked(MouseEvent e) {
if (e.getComponent() instanceof JComponent) {
JComponent jComponent = (JComponent) e.getComponent();
Object property = jComponent.getClientProperty(JComponentClickCountListener.class);
if (property instanceof Number) {
property = ONE + ((Number) property).intValue();
}
else {
property = ONE;
}
jComponent.putClientProperty(JComponentClickCountListener.class, property);
}
}
}
Then in your code you can decide to have a single instace of that class for all of your components or create a new one each time.
This could give you the advantage of using the propertyChangeListener for future actions.
PS.
The code example do not represent all logic for OP question but i could by used as solid base. Later on i will try to update it. To cover that.
EDIT2:
I think that you should separate the logic, of selection and action over selected items. Then the task is divided into two tasks. First is the possibility to store the information about it state, clicked active, clicked again inactive. The second tasks it to operate on that status when a jComponent status was changed.
This is an simple example that i wrote, the functionality is to highlight the background of labels when the are selected and remove it when it was clicked again or the panel was clicked remove all selections.
This example is divided to three elements Enum, Iterface and class that manage the logic of selection
Enum - we store the possible statuses and a property key.
public enum JComponentActivationStatus {
NONE,
ACTIVE,
INACTIVE;
public static final String PROPERTY_KEY = JComponentActivationStatus.class.getCanonicalName();
}
Interface - provide a delegate for action to be taken when jcomponenet status change.
public abstract interface JComponenetActivationStatusChangeAction<T extends JComponent> {
public abstract void onActivation(T object);
public abstract void onDeactivation(T object);
}
Class - This class mange the status logic of jcomponents.
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.JComponent;
public class JComponenetActivationManager {
public static <T extends JComponent> T addMouseStatusControl(T jComponent) {
jComponent.addMouseListener(new JComponentMouseStatusModyfier());
return jComponent;
}
public static <T extends JComponent> T addActivationStatusChangeAction(T jComponenet, JComponenetActivationStatusChangeAction<T> statusChangeAction) {
jComponenet.addPropertyChangeListener(craeteJCompositeActivationStatusChangeListener(statusChangeAction));
return jComponenet;
}
public static <T extends JComponent> PropertyChangeListener craeteJCompositeActivationStatusChangeListener(JComponenetActivationStatusChangeAction<T> action) {
return new JComponentStatusPropertyChangeListener<T>(action);
}
/**
* Class that set the status for the JComponet after doubClicl
*/
private final static class JComponentMouseStatusModyfier extends MouseAdapter {
#Override
public void mouseClicked(MouseEvent e) {
if(e.getComponent() instanceof JComponent) {
JComponent jComponent = (JComponent) e.getComponent();
Object propertyValue = jComponent.getClientProperty(JComponentActivationStatus.PROPERTY_KEY);
if(JComponentActivationStatus.ACTIVE.equals(propertyValue)) { //We check that the ACTIVE status is already selected, if so we inactive.
propertyValue = JComponentActivationStatus.INACTIVE; //If so we inactive it.
} else {
propertyValue = JComponentActivationStatus.ACTIVE; // Otherwise we set it as active
}
jComponent.putClientProperty(JComponentActivationStatus.PROPERTY_KEY, propertyValue); // We use the property key form status
}
}
}
/**
* Help class that fire the actions after status is changed
*/
private static final class JComponentStatusPropertyChangeListener<T extends JComponent> implements PropertyChangeListener {
private final JComponenetActivationStatusChangeAction<T> statusChangeAction;
/**
*
*/
public JComponentStatusPropertyChangeListener(JComponenetActivationStatusChangeAction<T> statusChangeAction) {
if(statusChangeAction == null) {
throw new IllegalArgumentException("action can not be null at this point");
}
this.statusChangeAction = statusChangeAction;
}
#Override
public void propertyChange(PropertyChangeEvent evt) {
if(JComponentActivationStatus.PROPERTY_KEY.equals(evt.getPropertyName())) {
if(JComponentActivationStatus.ACTIVE.equals(evt.getNewValue())) {
statusChangeAction.onActivation((T) evt.getSource());
}
if(JComponentActivationStatus.INACTIVE.equals(evt.getNewValue())){
statusChangeAction.onDeactivation((T) evt.getSource());
}
}
}
}
}
That class contain two public static method, that allow the developer to add the functionality to mange status to any jComponent object, add subscribe the action handler if any change occur.
At the end we have the main method that test our solution
public static void main(String[] args) {
JFrame frame = new JFrame();
JPanel panel = new JPanel();
JLabel l1 = new JLabel("Label 1");
JLabel l2 = new JLabel("Label 2");
JLabel l3 = new JLabel("Label 3");
panel.setBackground(Color.CYAN);
addMouseStatusControl(panel);
addMouseStatusControl(l1);
addMouseStatusControl(l2);
addMouseStatusControl(l3);
JComponenetActivationStatusChangeAction<JLabel> activeBackground = new JComponenetActivationStatusChangeAction<JLabel>() {
#Override
public void onActivation(JLabel object) {
object.setOpaque(true);
object.setBackground(Color.YELLOW);
}
#Override
public void onDeactivation(JLabel object) {
object.setOpaque(false);
object.setBackground(object.getParent().getBackground());
}
};
JComponenetActivationStatusChangeAction<JPanel> deactivateChildrens = new JComponenetActivationStatusChangeAction<JPanel>() {
#Override
public void onDeactivation(JPanel object) {
}
#Override
public void onActivation(JPanel object) {
for(Component component : object.getComponents()) {
if(component instanceof JComponent) {
((JComponent) component).putClientProperty(JComponentActivationStatus.PROPERTY_KEY,JComponentActivationStatus.INACTIVE);
}
}
}
};
addActivationStatusChangeAction(l1, activeBackground);
addActivationStatusChangeAction(l2, activeBackground);
addActivationStatusChangeAction(l3, activeBackground);
addActivationStatusChangeAction(panel, deactivateChildrens);
panel.add(l1);
panel.add(l2);
panel.add(l3);
frame.add(panel);
frame.pack();
frame.setVisible(true);
}
The solution is very flexible and extendable in case you will need to add more labels.
The example is for those that want to learn. Any comment would be appreciate.

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