java - PaintComponent 不绘制图 block 或绘制字符串

Question

我为我的学校项目编写了一些代码，使用二维数组和函数 PaintComponent 创建 10 x 10 的网格。

我的问题是它不显示网格或显示字符串。 (编译器不会显示任何错误。)

这是我的代码:

Board.java

public class Board extends JComponent implements KeyListener{

    public Board() {

    }

    public static String[] gameElements = new String[100];


    private String[][] map = new String[10][10];
    private String currentLevel = "1";
    private boolean paintComponentExecuted = false;
    Player hero;


    @Override
    public void paintComponent(Graphics g) {
        if(paintComponentExecuted == false) {
            loadLevel();
            int i = 0;
            int positionX = 50;
            int positionY = 50;
            for (int y = 0; y < map.length; y++) {
                for (int x = 0; x < map.length; x++) {
                    new Tile(x, y).paintComponent(g);
                    g.drawString(gameElements[i], positionY, positionX);
                    map[y][x] = gameElements[i];
                    positionY += 50;
                    System.out.print("[" + map[y][x] + "]");
                    i++;
                }
                positionY = 50;
                positionX += 50;
                System.out.println();
                paintComponentExecuted = true;

            }
        }
    }

    public void readTextFile(String fileName) {
        try {
            FileReader fileReader = new FileReader(fileName + ".txt");
            BufferedReader buffer = new BufferedReader(fileReader);
            String splitBy = ",";
            String line = buffer.readLine();

            for (int i = 0; i < gameElements.length; i++) {
                gameElements = line.split(splitBy);
            }

        } catch (FileNotFoundException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IOException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    public void loadLevel() {
        readTextFile(currentLevel);
    }

    public static void main(String[] args) {

        JFrame frame = new JFrame();
        frame.setSize(600, 600);
        frame.setTitle("SleutelBarricade");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JComponent chart = new Board();
        frame.add(chart);

        frame.setVisible(true);


    }

    @Override
    public void keyTyped(KeyEvent e) {

    }

    @Override
    public void keyPressed(KeyEvent e) {

    }

    @Override
    public void keyReleased(KeyEvent e) {

    }
}

瓷砖.java

public class Tile extends Board {

    public Tile() {

    }

    final private static int CELL_WIDTH = 50;
    final private static int CELL_HEIGHT = 50;

    final private static int BOARD_X_OFFSET = 25;
    final private static int BOARD_Y_OFFSET = 25;

    private int x;
    private int y;

    private int getScreenX(int x, int y) {
        return BOARD_X_OFFSET + x * CELL_WIDTH;
    }

    private int getScreenY(int x, int y) {
        return BOARD_Y_OFFSET + y * CELL_HEIGHT;
    }

    public Tile(int x, int y) {
        this.x = x;
        this.y = y;
    }

    @Override
    public void paintComponent(Graphics g) {
        g.setColor(Color.BLACK);
        g.drawRect(
                getScreenX(x, y),
                getScreenY(x, y),
                CELL_WIDTH,
                CELL_HEIGHT);

    }

}

提前致谢!

Answer 1

您必须删除此条件:

if(paintComponentExecuted == false) {


  paintComponentExecuted = true;
}

将该 block 的其余内容保留在那里。不要堵塞油漆重新油漆；否则你只会看到一次，再也不会出现。

您需要在构造函数中创建图 block :

假设你有这个全局变量

Tile tiles=new Tile[10][10];

然后在构造函数中

   for (int y = 0; y < tiles[0].length; y++)
      for (int x = 0; x < tiles.length; x++)
        tiles[x][y]=new Tile(x, y);

然后在你调用的paintComponent中

tiles[x][y].paintComponent(g);

此外，Tile 最好不要扩展任何东西，因为您是在板上绘图。也许其中一些会有所帮助。