面板的java坐标规范

Question

如何指定以下面板的坐标，而不是使其与中心对齐

我已经尝试了很多，使用了不同的布局，但仍然无法让它工作。请帮我解决这个问题。谢谢

这是我的密码

import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;

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

public class Lesson2 extends JFrame {

    private static final long serialVersionUID = -198253288329146091L;
    private JPanel contentPane;

    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    Lesson2 frame = new Lesson2();
                    frame.pack();
                    frame.setLocationRelativeTo(null);
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * Create the frame.
     */
    public Lesson2() {

        contentPane = new JPanel();
        setContentPane(contentPane);

        JPanel panel = new JPanel() {

            private static final long serialVersionUID = -5974584127539186578L;

            @Override
            protected void paintComponent(Graphics g) {
                super.paintComponent(g);
                g.setColor(Color.GREEN);
                g.fillRect(0, 0, 500, 500);
            }

            @Override
            public Dimension getPreferredSize() {
                return new Dimension(500, 500);
            }

        };

        contentPane.add(panel);

    }

}

下面是一个它现在看起来如何的例子 https://prnt.sc/moe3al

下面是使用设置大小的空布局编辑的最终代码

import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Graphics;

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

public class Lesson1 extends JFrame {

    private static final long serialVersionUID = -198253288329146091L;
    private JPanel contentPane;

    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    Lesson1 frame = new Lesson1();
                    frame.setSize(1000, 1000);
                    frame.setLocationRelativeTo(null);
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * Create the frame.
     */
    public Lesson1() {

        contentPane = new JPanel();
        setContentPane(contentPane);
        contentPane.setLayout(null);

        JPanel panel = new JPanel() {

            private static final long serialVersionUID = -5974584127539186578L;

            @Override
            protected void paintComponent(Graphics g) {
                super.paintComponent(g);
                g.setColor(Color.GREEN);
                g.fillRect(0, 0, 500, 500);
            }
        };

        panel.setLayout(null);
        panel.setSize(500, 500);

        contentPane.add(panel);

    }

}

Answer 1

所有Swing/AWT容器都使用FlowLayout作为默认布局管理器，这会导致组件居中。如果需要更多控制，可以通过调用contentPane使用Absolute Positioning。setLayout（null）并通过面板设置组件的坐标。setBounds（），但请注意，它可能无法优雅地调整窗口大小