Java Swing mousePressed 和 getSource() 未在 JPanel 上显示绘制的形状

Question

我目前正在尝试开发一个谜题。我得到的只是我的应用程序以及我的游戏 field 和游戏组件。下一步是单击我的一个游戏 block 以选择它，并能够使用箭头键移动它(此外，我希望它们仅移动，如果下一步(将是 100 像素)不包含任何其他游戏件)。

我当前遇到的问题:在我的主 JPanel 上使用 addMouseListener() ，然后使用 getSource() 仅返回我的Playing-field(在我的代码中称为 View)，但我需要它返回所需的游戏 block (例如 topLeft)。我已经尝试将 getSource() 转换为 Piece，但这不起作用(无法将 View 转换为 Piece)。

因此，我需要找到一种方法来添加鼠标监听器，该监听器返回被单击的游戏 block ，以便我可以更改位置并检查与任何其他游戏 block 的任何碰撞。提前致谢!

感谢@camickr编辑了代码。

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Polygon;
import java.awt.Rectangle;
import java.awt.Shape;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.AffineTransform;
import java.util.ArrayList;
import java.util.List;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;

public class Puzzle {

    public static void main(String[] args) {
        SwingUtilities.invokeLater(Puzzle::new);
    }

    private final static int[] SHAPE_X = { -100, 100, 100, 0, 0, -100 };
    private final static int[] SHAPE_Y = { -100, -100, 0, 0, 100, 100 };

    public Puzzle() {
        JFrame frame = new JFrame("Puzzle");
        frame.setSize(400, 600);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        View view = new View();
        frame.setContentPane(view);
        view.addMouseListener(new MouseAdapterMod(view));

        Shape polyShape = new Polygon(SHAPE_X, SHAPE_Y, SHAPE_X.length);
        Piece topLeft = new Piece(Color.YELLOW, polyShape,   0, 100, 100);
        view.pieces.add(topLeft);

        Piece topRight = new Piece(Color.CYAN, polyShape, 90, 300, 100);
        view.pieces.add(topRight);

        Piece bottomRight = new Piece(Color.GREEN,  polyShape, 180, 300, 300);
        view.pieces.add(bottomRight);

        Piece bottomLeft = new Piece(Color.RED,  polyShape, 270, 100, 300);
        view.pieces.add(bottomLeft);

        Piece square = new Piece(Color.ORANGE, new Rectangle(200, 200), 0, 100, 100);
        view.pieces.add(square);

        frame.setVisible(true);
    }

}

class View extends JPanel {

    final List<Piece> pieces = new ArrayList<>();

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);

        Graphics2D gc = (Graphics2D) g;
        for (Piece piece : pieces) {
            piece.draw(gc);
        }

    }
}

class Piece {
    final Color color;
    final Shape shape;
    final int angle;

    int x;
    int y;

    Piece(Color color, Shape shape, int angle, int x, int y) {
        this.color = color;
        this.shape = shape;
        this.angle = angle;
        this.x = x;
        this.y = y;
    }

    void draw(Graphics2D gc) {
        AffineTransform tf = gc.getTransform();
        gc.translate(x, y);
        gc.rotate(Math.toRadians(angle));
        gc.setColor(color);
        gc.fill(shape);
        gc.setTransform(tf);
    }

    Shape getShape() {
    return shape;
    }
}

class MouseAdapterMod extends MouseAdapter {

    final View view;

    public MouseAdapterMod(View view) {
    this.view = view;
    }

    @Override
    public void mousePressed(MouseEvent e) {
    for(Piece piece : view.pieces) {
        if(piece.getShape().contains(e.getX(), e.getY())) {
        System.out.println("yes");
        }
    }
    }
}

Answer 1

So, I need to find a way to add a mouse listener which returns the gaming-piece that was clicked

您可以使用 MouseEvent 中的 getX() 和 getY() 方法。

然后，您迭代“ block ”ArrayList，并对每个 Piece 中包含的 Shape 调用 contains(... 方法查看鼠标点是否包含在棋子中。

因此，您还需要向“Piece”类添加一个 getShape(...) 方法，以便可以访问每个 Piece 的 Shape .

编辑:

所以你的基本逻辑可能是这样的:

//Shape polyShape = new Polygon(SHAPE_X, SHAPE_Y, SHAPE_X.length);
//Piece topLeft = new Piece(Color.YELLOW, polyShape,   0, 100, 100);
Polygon topLeftPolygon = new Polygon(SHAPE_X, SHAPE_Y, SHAPE_X.length);
topLeftPolygon.translate(100, 100);
//topLeftPolygon = ShapeUtils.rotate(...); // do rotation when required
Piece topLeft = new Piece(Color.YELLOW, topLeftPolygon);

那么draw(..)方法中的绘画代码就是:

gc.setColor(color);
gc.fill(shape);

无需转换或翻译。

编辑2:

所以使用形状:

//topLeftPolygon = ShapeUtils.rotate(...); // do rotation when required
//Piece topLeft = new Piece(Color.YELLOW, topLeftPolygon);
Shape topLeftShape = ShapeUtils.rotate(...); // do rotation when required
Piece topLeft = new Piece(Color.YELLOW, topLeftShape);

这当前与您的 Piece 类匹配，无论如何它都需要一个 Shape 对象。请考虑所建议的概念，不要假设发布的代码是完美的，因为它显然尚未经过测试。