Java 鼠标监听器不工作

Question

当鼠标在 RenderCanvas 类的对象内按下时，我试图让控制台打印，该类扩展 JPanel。但是，当我在窗口中按下鼠标时，我没有收到任何反馈。关于我可以更改哪些内容以使 MouseListener 正常工作，有什么建议吗？

这是我的代码:

RenderCanvas 类:

import java.awt.event.MouseEvent;
import java.util.ArrayList;
import java.util.List;
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JPanel;
import java.awt.event.MouseAdapter;


public class RenderCanvas extends JPanel {
    private List<Rect> rectangles = new ArrayList<Rect>();
    private List<Line> lines = new ArrayList<Line>();

    public void renderCanvas() {
        addMouseListener(new MouseAdapter() {
            public void mousePressed(MouseEvent e) {
                addRect(0, 0, 200, 200, Color.ORANGE);
                System.out.println(e);
            }
        });
    }

    public void paintComponent(Graphics g) {
        for (Rect rectangle : rectangles) {
            rectangle.draw(g);
        }
        for (Line line : lines) {
            line.draw(g);
        }
    }

    public void addRect(int x, int y, int width, int height, Color color) {
        Rect rectangle = new Rect(x, y, width, height, color);
        this.rectangles.add(rectangle);
    }

    public void addLine(int y, int width, Color color) {
        Line line = new Line(y, width, color);
        this.lines.add(line);
    }
}

主类:

import javax.swing.*;
import java.awt.*;
import java.util.Random;

public class Main {
    public static void main(String[] args) {
        JFrame window = new JFrame("Window");
        RenderCanvas canvas = new RenderCanvas();
        window.setContentPane(canvas);
        window.setSize(640, 360);
        window.setLocation(640, 360);
        window.setVisible(true);
    }
}

预先感谢您的帮助!

Answer 1

public void renderCanvas() 不是构造函数。改变

public void renderCanvas()

至

public RenderCanvas()

注意大写的“R”并且没有“void”返回类型