paintComponent() 没有正确绘制矩形

Question

I have a painted grid of custom rectangles inside a JPanel. I have rectangles stored in a list of rectangles. I have added a MouseMotionListener and a MouseListener to the JPanel; Both of these components will listen to either the users click or their click and hold, find out the position of where the mouse reticle is, loop through my list of rectangles and update its enum value accordingly. I then call repaint() to redraw the rectangles in the list on JPanel. The only thing is that on repainting the list, instead of just painting that one rectangle, it paints the entire column. Please Help.

My Initialization of the initial rectangle list

for(int i = 0; i < 10; i++)
        {
            for(int j = 0; i < 10; i++)
            {
                initList.add(new PathRectangle(i*49, j*49, 49, 49));
            }
        }
        
        mainPanel = new MainPanel(10, 10, initList);
        mainFrame.add(mainPanel);

My Rectangle Class

import  java.awt.*;

public class PathRectangle extends Rectangle
{

    private recType recVal = recType.UNDECLARED;

    //double pythHeurVal, manhattanHeurVal;

    public PathRectangle(int x, int y, int width, int height)
    {
        super(x, y, width, height);
    }

    public enum recType{WALL, STARTNODE, ENDNODE, UNDECLARED}

    public recType getRecVal() {
        return this.recVal;
    }

    public void setRecVal(recType wall) {
        this.recVal = wall;
    }


}

Adding Mouse Motion Listener

addMouseMotionListener(new MouseAdapter()
        {
            @Override
            public void mouseDragged(MouseEvent e) 
            {
                   //System.out.println(e.getPoint());
                    for(int i = 0; i < paintedRectangles.size(); i++)
                    {
                        if(paintedRectangles.get(i).contains(e.getPoint()))
                        {
                            //This will have to change in the future just testing it right now
                            paintedRectangles.get(i).setRecVal(PathRectangle.recType.WALL);
                            
                            
                            repaint();
                        }
                    }
            }
        });

Adding MouseListener

addMouseListener(new MouseAdapter()
        {
           
            @Override
            public void mousePressed(MouseEvent e) {
                
                for(int i = 0; i < paintedRectangles.size(); i++)
                    {
                        if(paintedRectangles.get(i).contains(e.getPoint()))
                        {
                            //This will have to change in the future just testing it right now
                            paintedRectangles.get(i).setRecVal(PathRectangle.recType.WALL);
                            
                            
                            repaint();
                        }
                    }
            }
        });

paintComponent method

public void paintComponent(Graphics g)
    {
        super.paintComponent(g);

        Graphics2D g2D = (Graphics2D) g;

        for(int i = 0; i < rows; i++)
        {
            for(int j = 0; j < cols; j++)
            {
                
                switch(paintedRectangles.get(i).getRecVal())
                {
                    case UNDECLARED:
                    g2D.drawRect(i*rectLenWidSize, j*rectLenWidSize, rectLenWidSize, rectLenWidSize);
                    break;

                    case WALL:
                    g2D.setColor(Color.BLACK);
                    g2D.fillRect(i*rectLenWidSize, j * rectLenWidSize, rectLenWidSize, rectLenWidSize);
                    break;

                    case STARTNODE:
                    g2D.setColor(Color.GREEN);
                    g2D.fillRect(i*rectLenWidSize, j*rectLenWidSize, rectLenWidSize, rectLenWidSize);
                    break;

                    case ENDNODE:
                    g2D.setColor(Color.RED);
                    g2D.fillRect(i*rectLenWidSize, j*rectLenWidSize, rectLenWidSize, rectLenWidSize);
                    break;
                }
            }
        }
    }

Answer 1

To do something like this you are going to need two-dimensional ArrayLists. One-dimensional ArrayLists don't represent the Grid correctly.

I also noticed I made a couple mistakes when making the first initialization ArrayList

My Initialization of the initialization of the rectangle list

for(int i = 0; i < 10; i++)
        {
            ArrayList<PathRectangle> initColList = new ArrayList<PathRectangle>();

            for(int j = 0; j < 10; j++)
            {
                initColList.add(new PathRectangle(i*49, j*49, 49, 49));
            }

            initList.add(initColList);
        }

paintComponent method

public void paintComponent(Graphics g)
{
    super.paintComponent(g);
    
    Graphics2D g2D = (Graphics2D) g;

    for(int i = 0; i < paintedRectangles.size(); i++)
    {
        for(int j = 0; j < paintedRectangles.get(0).size(); j++)
        {
            
            //System.out.println(paintedRectangles.get(i).get(j).getRecVal());
            switch(paintedRectangles.get(i).get(j).getRecVal())
            {
                case UNDECLARED:
                g2D.drawRect(i*rectLenWidSize, j*rectLenWidSize, rectLenWidSize, rectLenWidSize);
                break;

                case WALL:
                g2D.setColor(Color.BLACK);
                g2D.fillRect(i*rectLenWidSize, j * rectLenWidSize, rectLenWidSize, rectLenWidSize);
                break;

                case STARTNODE:
                g2D.setColor(Color.GREEN);
                g2D.fillRect(i*rectLenWidSize, j*rectLenWidSize, rectLenWidSize, rectLenWidSize);
                break;

                case ENDNODE:
                g2D.setColor(Color.RED);
                g2D.fillRect(i*rectLenWidSize, j*rectLenWidSize, rectLenWidSize, rectLenWidSize);
                break;
            }
        }
    }
}