Question

我必须做一个练习，需要在左边放置一个黑色JPanel，我必须在那里画一个星形 GeneralPath和一些按钮右边必须移动该通用路径，再加上一个重置按钮，它将在面板中间设置一般路径的位置。

这是代码：

import java.awt.*;
import java.awt.geom.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.border.*;

public class SunGUI extends JFrame {
    private Space space;
    private Control control;
    private final int DELTA = 50;
    private int posX, posY;

    public SunGUI() {
        Container cnt = getContentPane();

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLayout(new BorderLayout());

        space = new Space();
        control = new Control();

        cnt.add(space, BorderLayout.CENTER);
        cnt.add(control, BorderLayout.EAST);

        pack();
        setVisible(true);

    }

    public class Space extends JPanel {
        private GeneralPath sun;

        public Space() {
            setPreferredSize(new Dimension(800, 600));
            sun = createSun();

        }

        public GeneralPath createSun() {
            GeneralPath sun = new GeneralPath();

            sun.moveTo(-30, -30);
            sun.lineTo(50, 50);
            sun.moveTo(50, -30);
            sun.lineTo(-30, 50);
            sun.moveTo(10, -35);
            sun.lineTo(10, 55);
            sun.moveTo(-35, 10);
            sun.lineTo(55, 10);
            sun.moveTo(-5, -25);
            sun.lineTo(25, 45);
            sun.moveTo(25, -25);
            sun.lineTo(-5, 45);
            sun.moveTo(-25, -5);
            sun.lineTo(45, 25);
            sun.moveTo(45, -5);
            sun.lineTo(-25, 25);

            sun.closePath();
            return sun;

        }

        @Override
        public void paintComponent(Graphics g) {
            super.paintComponent(g);
            Graphics2D g2 = (Graphics2D)g;

            setBorder(BorderFactory.createLineBorder(Color.red));
            setBackground(Color.black);

            g2.setPaint(Color.white);
            g2.draw(sun);

        }
    }

    public class Control extends JPanel {
        private JButton up, down, left, right, reset;
        private JPanel arrows, panel, resetPanel, container;

        public Control() {
            setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));

            panel = new JPanel();
            arrows = new JPanel();
            resetPanel = new JPanel();
            container = new JPanel();

            arrows.setLayout(new GridLayout(1, 4));
            resetPanel.setLayout(new GridLayout(1, 1));
            container.setLayout(new GridLayout(2, 1));

            up = new JButton("^");
            down = new JButton("v");
            left = new JButton("<");
            right = new JButton(">");
            reset = new JButton("R");

            arrows.add(up);
            arrows.add(left);
            arrows.add(right);
            arrows.add(down);

            resetPanel.add(reset);

            container.add(arrows);
            container.add(resetPanel);
            arrows.setPreferredSize(new Dimension(160, 20));
            resetPanel.setPreferredSize(new Dimension(160, 20));

            panel.add(container);
            panel.setBorder(new TitledBorder("Comandi"));
            add(panel);

        }
    }

    public static void main(String args[]) {
        new SunGUI();

    }
}

现在这段代码只会在左上角显示一个带有星形常规路径的静态GUI，但我想要做的是把它放在黑色的中间面板。

我在网上搜索过但我一无所获，是否有人有想法？

Answer 1

super.paintComponent(g);
AffineTransform move = AffineTransform.getTranslateInstance(x,y);
g.setTransform(move);
// draw the shape...

Answer 2

您可以使用g2.translate翻译整个图形上下文，由Andrew Thompson回答（然后重置转换），或使用AffineTransform的createTransformedShape方法仅转换形状。以下是一个示例：How to have rotated Ellipse shape in Java?

如何在JPanel中设置GeneralPath的位置？

2 个答案: