更改网格中矩形的颜色

Question

I need help changing the color of a rectangle in a grid. So far, I have the rectangles and the grid (which are lines drawn separating the rectangles), and I want to change the color of a single rectangle when it's clicked.

I added the line "System.out.println("Something")" in the loop where the color is supposed to change, and it always returns "Something." That's why I'm confused. Thanks for any and all help!

Class Grid:

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.util.ArrayList;
import javax.swing.Timer;
import javax.swing.JFrame;
import javax.swing.JPanel;

 public class Grid extends JPanel{

private int a = 50;
private int b = 50;
private Lifeform[][] Life;
private boolean[][]life = new boolean[a][b];
private Timer t;

Grid(){
//creates grid of rectangles
    Life = new Lifeform[a][b];

    int ypos = 0;
    for(int i = 0; i < Life.length; i++){
        int xpos = 0;
        for(int j = 0; j < Life[0].length; j++){

            Rectangle r = new Lifeform();
            r.setBounds(xpos, ypos, 50, 50);
            Life[i][j] = (Lifeform) r;
            xpos += 50;
        }
        ypos += 50;
    }
    t = new Timer(64, new Movement());
    this.addMouseListener(new mouse());
}

public void paintComponent(Graphics g){

    for(Lifeform[] n : Life){
//makes rectangles white
        g.fillRect(this.getX(), this.getY(), this.getWidth(), this.getHeight());
        g.setColor(Color.white);
    }
    for (int i = 0; i <= 25; i++){
        g.drawLine(0, 50*i, 1500, 50*i);
        g.setColor(Color.black);
    }
    for (int i = 0; i <= 25; i++){
        g.drawLine(50*i, 0, 50*i, 750);
        g.setColor(Color.black);
    }
}

private JFrame createGrid(){

    JFrame frame = new JFrame("Alveolate");
    frame.add(this);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(700,700);
    frame.setVisible(true);     
    return frame;
}

public class mouse implements MouseListener{
//colors rectangles (it doesn't work)
    public void mouseClicked(MouseEvent e) {
        Point p = new Point(e.getX(),e.getY());
        for(int i = 0; i < Life.length; i++){
            for(int j = 0; j < Life[i].length; j++){
                Lifeform spot = Life[i][j];

                if (spot.contains(p)){
                    spot.setColor(Color.red);
                    System.out.println("Something");

                }
            }

        }   

    }

    public void mousePressed(MouseEvent e) {}
    public void mouseReleased(MouseEvent e) {}
    public void mouseEntered(MouseEvent e) {}       
    public void mouseExited(MouseEvent e) {}

}

public class Movement implements ActionListener{
    public void actionPerformed ( ActionEvent e ){

        for (int i = 0; i < Life.length; i++){
            for (int j = 0; j < Life[i].length; j++){
                if(Life[i][j].getColor().equals(Color.black)){
                    life[i][j] = true;
                }
                else{
                    life[i][j] = false;
                }

            }       

        }

        repaint();

    }

}

public void startTimer(){
    t.start();
}

public void stopTimer(){
    t.stop();
}

public static void main(String[] args) {

    Grid ABC = new Grid();
    ABC.createGrid();
    ABC.startTimer();
}
}

Class Lifeform:

import java.awt.Color; import java.awt.Rectangle;

public class Lifeform extends Rectangle {
    private Color c;
    public Lifeform() {
        c = Color.WHITE;
    }
    public Color getColor() {
        return c;
    }

    public boolean setColor( Color c ) {
        boolean rtn = false;
        if( c != null ) {
            this.c = c;
            rtn = true;
        }

        return rtn;
    }

    }

Answer 1

try this:

for(int i = 0; i < 50; i++){
   for(int j = 0; j < 50; j++){
    ....  

   }
}

Answer 2

try

for(Lifeform[] n : Life){
    for(Lifeform lf : n){
        g.setColor(lf.getColor());
        g.fillRect((int)lf.getX(), (int)lf.getY(), (int)lf.getWidth(), (int)lf.getHeight());
    }
}

in your paintComponent method

Answer 3

Didn't read all you code but it seems like you definitely set the color of your Lifeform to red. This means that your rendering code never actually uses this fact to display that Lifeform. It seems like the only time you draw your rectangles is in paintComponent. This paint needs to be called each time you want a redraw to happen. You can use repaint on your JFrame or JPanel to get this to happen. Also, the render code you have there seems to only ever display white rectangles

g.fillRect(this.getX(), this.getY(), this.getWidth(), this.getHeight());
g.setColor(Color.white);

This is in a loop through your Lifeform[][]. Instead you should probably have a double for loop to get every Lifeform and use the x and y and color from that to draw. Something like:

g.fillRect(Life[i][j].getX(), Life[i][j].getY(), ..., ..., Life[i][j].getColor())

Also, Life should be named life with a lowercase 'l'. It's way confusing seeing names without conventions.