Image not showing on JLabel

Question

I've been tasked to make a java replica of Candy Crush Saga. Right now im quite stuck on the GUI part. I've decided that each candy will be represented by a JLabel holding the candy icon, and a mouselistener to control the functionality. What happens is, after i finish running the screen shows, the mouse listeners respond but the image doesn't show, meaning i can press the labels get a response but cannot see the icons. I take this as the labels are on the panel but somehow not visible or the icon is not loaded correctly - although when checking the ImageIcon.toString it shows the path to the file. Any ideas?

Here is the code:

public class Board extends JPanel {
Candy[][] board;
static final int TILE_SIZE = 55;
static final int  TILES_MARGIN = 8;


public Board() {
    setFocusable(true);

    board = new Candy[13][13];
    Candy c;
    for (int i = 0; i < 13; i++)
        for (int j = 0; j < 13; j++) {
            if (i != 0 && i != 1 && j != 0 && j != 1 && i != 11 && i != 12 && j != 11 && j != 12) {
                Random rand = new Random();
                int randomNum = rand.nextInt((6 - 1) + 1) + 1;
                c = new Basic(randomNum, this);
            } else {
                c = new Basic(0, this);
            }
            setAt(i, j, c);
        }
    repaint();
}

public void drawCandy(Graphics g2, Candy candy, int x, int y) {
    Graphics2D g = ((Graphics2D) g2);
    g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
    g.setRenderingHint(RenderingHints.KEY_STROKE_CONTROL, RenderingHints.VALUE_STROKE_NORMALIZE);
    int value = candy.getClr();
    int xOffset = offsetCoors(x);
    int yOffset = offsetCoors(y);
    ImageIcon myImg = candy.switchIcon();
    JLabel toAdd = new JLabel(myImg);
    toAdd.setIcon(myImg);
    toAdd.setLocation(xOffset,yOffset);
    toAdd.setSize(TILE_SIZE,TILE_SIZE);
    toAdd.addMouseListener(new ButtonPressed(x,y,candy));
    toAdd.setVisible(true);
    if (value != 0)
        add(toAdd);
}
private static int offsetCoors(int arg) {
    return (arg-2) * (TILES_MARGIN + TILE_SIZE) + TILES_MARGIN;
}

public void paint(Graphics g) {
    super.paint(g);
    removeAll();
    requestFocusInWindow();
    g.setColor(Color.black);
    g.fillRect(0, 0, this.getSize().width, this.getSize().height);

    for (int x = 2; x < 11; x++) {
        for (int y = 2; y < 11; y++) {
            drawCandy(g, board[x][y], x, y);
        }
    }

    validate();
}

and the JFrame :

public Game() {
    super("Candy Crush Game");
    setDefaultLookAndFeelDecorated(true);
    setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    getContentPane().setLayout(new BorderLayout());
    setSize(600, 600);
    setResizable(false);
    setLocationRelativeTo(null);
    this.board = new Board();


    this.score = 0;
    this.moves = 20;

    this.getContentPane().add(board, BorderLayout.CENTER);
    setVisible(true);


     board.checkSquare(2, 2, 10, 10);


}

I'm quite frustrated, any help will be great!

`removeAll(); requestFocusInWindow();` Don't call these methods from within a paint method. — Andrew Thompson, Jun 14 '14 at 10:06
Please share a minimal testable code. Are you able to get the images? — Braj, Jun 14 '14 at 10:13
I've tried removing both requestFocus and removeAll. Still doesnt show Images. Do i have to call removeAll? i mean the code gets called quite a few times because the board gets updated, is it necessary to remove all labels before adding them back? — vito, Jun 14 '14 at 10:17

score 3 · Accepted Answer · edited May 23 '17 at 12:23

3

Instead of overriding paint() method use paintComponent() method for JPanel.

@Overrie
public void paintComponent(Graphics g) {
     super.paintComponent(g);
     //your custom painting here
}

There might be some issue in reading image icon. My another post might help you.

ImageIcon does not work with me

Instead of creating new JLabel simply change it's icon.

edited May 23 '17 at 12:23

Community

1
1

answered Jun 14 '14 at 10:05

Braj

46,415
5
60
76

That's great advice, but doesn't answer the question and Andrew hit on the main cause of the problem – MadProgrammer Jun 14 '14 at 10:10
The code is not complete, I can't test it. Meanwhile I am trying to investigate it. – Braj Jun 14 '14 at 10:11
Then you should have sake for more ;) Take close look at the paint method...and the fact that the OP doesn't understand how basic painting is done ;) – MadProgrammer Jun 14 '14 at 10:12
and instead of calling repaint() straightforward calling paintComponent() every time theres a change in the board? – vito Jun 14 '14 at 10:19
`repaint` internally call `paintComponent` – Braj Jun 14 '14 at 10:20
Thank you so much!! It really did the trick, replacing paint() with paintComponent() solved it! THANKS – vito Jun 14 '14 at 10:22
Oh another problem occurred. Now i'm getting all the boards painted. Meaning after every change at the board nothing gets deleted only added.. Is there a way around this? EDIT: ok, just added removeAll() inside the paintComponent() was good enough. – vito Jun 14 '14 at 10:25

Image not showing on JLabel

1 Answers1