I'm trying to draw lines between cells which are JLabel but fail to get their coordinates. The lines must follow a path from a startPoint to an endPoint.
In my View class, the below code creates the grid:
void createGrid(int rows, int cols) {
MyMouseListener listener = new MyMouseListener();
setRows(rows);
mainPanel.setLayout(new GridLayout(rows, cols, 1, 1));
mainPanel.setBorder(BorderFactory.createLineBorder(Color.BLACK));
mainPanel.setBackground(Color.DARK_GRAY);
grid = new JLabel[rows][cols];
for (int r = 0; r < grid.length; r++) {
for (int c = 0; c < grid[r].length; c++) {
grid[r][c] = new JLabel(iconMap.get(Token.VIDE));
grid[r][c].addMouseListener(listener);
grid[r][c].setOpaque(true);
grid[r][c].setBackground(Color.WHITE);
//grid[r][c].setPreferredSize(new Dimension(ICON_W, ICON_W));
mainPanel.add(grid[r][c]);
}
}
}
While this one creates the icons:
private Icon createIcon(Color color) {
BufferedImage img = new BufferedImage(ICON_W, ICON_W, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = img.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setColor(color);
g2.fillOval(1, 1, ICON_W - 2, ICON_W - 2); // int ICON_W = 20;
g2.dispose();
return new ImageIcon(img);
}
The whole code for the View class: https://pastebin.com/sgyn6rSR Code for the path algo: https://pastebin.com/Gcw9YVMF
I've tried something like below, but doesn't work
Graphics2D g2d = (Graphics2D) g.create();
for (JLabel[] grid : cells) {
g2d.setColor(Color.BLUE);
Point startPoint = grid[0].getLocation();
Point endPoint = grid[1].getLocation();
startPoint.x += (grid[0].getWidth() / 2);
startPoint.y += (grid[1].getHeight()/ 2);
endPoint.x += (grid[0].getWidth() / 2);
endPoint.y += (grid[1].getHeight()/ 2);
if(startPoint != null){
g2d.draw(new Line2D.Double(startPoint, endPoint));
}
startPoint = endPoint;
}
Here is the View class modified to add lines as requested.
Please review and see comments :
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.beans.PropertyChangeListener;
import java.util.EnumMap;
import java.util.Map;
import javax.swing.BorderFactory;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class View {
public static final String CELL_SELECTION = "cell selection";
private final static int GAP = 2;
private static int iconWidth;
private int rows;
private JPanel mainPanel;
private JLabel[][] grid;
private Map<Token, Icon> iconMap = new EnumMap<>(Token.class);
private int selectedRow;
private int selectedCol;
//a collection of cells representing a path
private CellsList path;
//a pane to hold two panels one on top of the other
JPanel layeredPanel;
View() {
mainPanel = new JPanel();
//add layerd pane to hold two panels one on top of the other
layeredPanel = new JPanel();
//set GridBagLayout to allow placing two components one on top of the other
layeredPanel.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 1;
gbc.weighty = 1;
gbc.fill = GridBagConstraints.BOTH;
//add main panel to layered panel
layeredPanel.add(mainPanel, gbc);
//create and add a drawing panel
DrawJPanel drawPanel = new DrawJPanel();
drawPanel.setOpaque(false); //set if to transparent so it does not
//hide mainPanel under it
layeredPanel.add(drawPanel, gbc);
//set z-order (depth) of two panels
layeredPanel.setComponentZOrder(mainPanel,1);
layeredPanel.setComponentZOrder(drawPanel,0);
}
void createGrid(int rows, int cols) {
MyMouseListener listener = new MyMouseListener();
setRows(rows);
setIcons();
mainPanel.setLayout(new GridLayout(rows, cols, 1, 1));
mainPanel.setBorder(BorderFactory.createLineBorder(Color.BLACK));
mainPanel.setBackground(Color.BLACK);
grid = new JLabel[rows][cols];
for (int r = 0; r < grid.length; r++) {
for (int c = 0; c < grid[r].length; c++) {
grid[r][c] = new JLabel(iconMap.get(Token.VIDE));
grid[r][c].addMouseListener(listener);
grid[r][c].setOpaque(true);
grid[r][c].setBackground(Color.WHITE);
mainPanel.add(grid[r][c]);
}
}
layeredPanel.setPreferredSize(mainPanel.getPreferredSize());
}
int getSelectedRow() {
return selectedRow;
}
int getSelectedCol() {
return selectedCol;
}
void setCell(Token token, int row, int col) {
grid[row][col].setIcon(iconMap.get(token));
}
int getRows() {
return rows;
}
void setRows(int rows) {
this.rows = rows;
}
//added to each cell to listen to mouse clicks
//fires property change with cell index
private class MyMouseListener extends MouseAdapter {
@Override
public void mousePressed(MouseEvent e) {
JLabel selection = (JLabel) e.getSource();
for (int r = 0; r < grid.length; r++) {
for (int c = 0; c < grid[r].length; c++) {
if (selection == grid[r][c]) {
selectedRow = r;
selectedCol = c;
int index = (r * grid[r].length) + c;
mainPanel.firePropertyChange(CELL_SELECTION, -1, index);
}
}
}
}
}
void start() {
JFrame frame = new JFrame("MVC Pha");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(layeredPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
//add listener to listen to property changes fired by MyMouseListener
void addPropertyChangeListener(PropertyChangeListener viewListener) {
mainPanel.addPropertyChangeListener(viewListener);
}
void setPath(CellsList path) {
this.path = path;
if(path != null) {
drawPath();
}
}
//highlight path by changing background color.
//It can be changed to draw lines between cells
private void drawPath() {
for (int row = 0; row < grid.length; row++) {
for (int col = 0; col < grid[row].length; col++) {
if((path != null) && path.contains(new int[] {row,col})) {
grid[row][col].setBackground(Color.YELLOW);
} else {
grid[row][col].setBackground(Color.WHITE);
}
}
}
}
//receives rectangle and returns its center point
private Point getComponentCenter(Rectangle bounds) {
int xCenter = (int) ((bounds.getX()+ bounds.getMaxX())/2);
int yCenter = (int) ((bounds.getMinY()+ bounds.getMaxY())/2);
return new Point(xCenter, yCenter);
}
void refresh() {
layeredPanel.repaint();
}
private void setIcons() {
if(rows <= 20) {
iconWidth = 24;
} else if( rows <= 40 ) {
iconWidth = 20;
} else if( rows <= 60 ) {
iconWidth = 15;
} else if( rows <= 80 ) {
iconWidth = 12;
} else {
iconWidth = 8;
}
iconMap.put(Token.VIDE, createIcon(new Color(0, 0, 0, 0)));
iconMap.put(Token.CERCLE_BLEU, createIcon(Color.BLUE));
iconMap.put(Token.CERCLE_ROUGE, createIcon(Color.RED));
}
private Icon createIcon(Color color) {
BufferedImage img = new BufferedImage(iconWidth, iconWidth, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = img.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setColor(color);
g2.fillOval(1, 1, iconWidth - GAP, iconWidth - GAP);
g2.dispose();
return new ImageIcon(img);
}
//a panel to draw line on
class DrawJPanel extends JPanel {
@Override
protected void paintComponent(Graphics g){
super.paintComponent(g);
if((path == null) || path.isEmpty() ) {
return;
}
//calculate points to construct line along the path
Point[] polygon = new Point[path.size()];
int i=0;
for(int[] address : path) { //iterate over path
//get cell location (row / col)
int row = address[0]; int col = address[1];
//get label in that location
JLabel lable = grid[row][col];
//add center of label as a point in polygon
polygon[i++] = getComponentCenter(lable.getBounds());
}
//draw points in polygon
g.setColor(Color.CYAN); //set line color and width
Graphics2D g2 = (Graphics2D) g;
g2.setStroke(new BasicStroke(2));
int j;
for (j = 0; j < (polygon.length -1); j++) {
Point point1 = polygon[j];
Point point2 = polygon[j+1];
g2.draw(new Line2D.Float(point1, point2));
}
//add line to connect last point to first
g2.draw(new Line2D.Float(polygon[j], polygon[0]));
}
}
}