摆动自定义边框答案

【问题标题】：Swing Custom Border摆动自定义边框
【发布时间】：2013-07-24 12:51:27
【问题描述】：

有什么方法可以实现自定义javax.swing.border.Border 如图所示？

【问题讨论】：

【解决方案1】：

您只需要扩展AbstractBorder 并覆盖其paintBorder() 方法，这是一个相关示例：

import java.awt.*;
import java.awt.event.*;
import java.awt.geom.Line2D;
import java.awt.geom.Line2D.Double;
import javax.swing.*;
import javax.swing.border.AbstractBorder;

public class CustomMarginBorder
{
    private JPanel contentPane;
    private CustomBorder customBorder;

    private void displayGUI()
    {
        JFrame frame = new JFrame("Custom Arrow Border Example");
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

        customBorder = new CustomBorder(Color.BLUE, 15);
        contentPane = new JPanel();     
        contentPane.setBorder(customBorder);    

        frame.setContentPane(contentPane);
        frame.setSize(300, 300);
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    public static void main(String[] args)
    {
        Runnable runnable = new Runnable()
        {
            @Override
            public void run()
            {
                new CustomMarginBorder().displayGUI();
            }
        };
        EventQueue.invokeLater(runnable);
    }
}

class CustomBorder extends AbstractBorder
{
    private Color borderColour;
    private int gap;

    public CustomBorder(Color colour, int g)
    {
        borderColour = colour;
        gap = g;
    }

    @Override
    public void paintBorder(Component c, Graphics g, int x, int y
                                                   , int width
                                                   , int height)
    {
        super.paintBorder(c, g, x, y, width, height);
        Graphics2D g2d = null;
        if (g instanceof Graphics2D)
        {
            g2d = (Graphics2D) g;
            g2d.setColor(borderColour);
            //Left Border
            g2d.draw(new Line2D.Double((double)x + 10, (double)y + 10
                                , (double)x + 10, (double)y + 20));
            g2d.draw(new Line2D.Double( (double)x + 10, (double)y + 10
                                , (double)x + 20, (double)y + 10));
            // Right Border
            g2d.draw(new Line2D.Double( (double)width - 10, (double)y + 10
                                , (double)width - 10, (double)y + 20));
            g2d.draw(new Line2D.Double( (double)width - 10, (double)y + 10
                                , (double)width - 20, (double)y + 10));
            // Lower Left Border
            g2d.draw(new Line2D.Double( (double)x + 10, (double)height - 10
                                , (double)x + 20, (double)height - 10));
            g2d.draw(new Line2D.Double( (double)x + 10, (double)height - 10
                                , (double)x + 10, (double)height - 20));
            // Lower Right Border
            g2d.draw(new Line2D.Double( (double)width - 10, (double)height - 10
                                , (double)width - 20, (double)height - 10));
            g2d.draw(new Line2D.Double( (double)width - 10, (double)height - 10
                                , (double)width - 10, (double)height - 20));
        }
    }

    @Override
    public Insets getBorderInsets(Component c)
    {
        return (getBorderInsets(c, new Insets(gap, gap, gap, gap)));
    }

    @Override
    public Insets getBorderInsets(Component c, Insets insets)
    {
        insets.left = insets.top = insets.right = insets.bottom = gap;
        return insets;
    }

    @Override
    public boolean isBorderOpaque()
    {
        return true;
    }
}

对于粗线边框使用这个：

class CustomBorder extends AbstractBorder
{
    private Color borderColour;
    private int gap;
    private double rectWidth;
    private double rectHeight;

    public CustomBorder(Color colour, int g, double w, double h)
    {
        borderColour = colour;
        gap = g;
        rectWidth = w;
        rectHeight = h;
    }

    @Override
    public void paintBorder(Component c, Graphics g, int x, int y
                                                   , int width
                                                   , int height)
    {
        super.paintBorder(c, g, x, y, width, height);
        Graphics2D g2d = null;
        if (g instanceof Graphics2D)
        {
            g2d = (Graphics2D) g;
            g2d.setColor(borderColour);
            //Left Border
            g2d.fill(new Rectangle2D.Double(
                                  (double)x + gap
                                , (double)y + gap
                                , rectWidth, rectHeight));
            g2d.fill(new Rectangle2D.Double(
                                  (double)x + gap
                                , (double)y + gap + rectHeight
                                , rectHeight, rectWidth));
            // Right Border
            g2d.fill(new Rectangle2D.Double(
                                  (double)width - gap - rectWidth
                                , (double)y + gap
                                , rectWidth, rectHeight));
            g2d.fill(new Rectangle2D.Double(
                                  (double)width - gap - rectHeight
                                , (double)y + gap + rectHeight
                                , rectHeight, rectWidth));
            // Lower Left Border
            g2d.fill(new Rectangle2D.Double(
                                  (double)x + gap
                                , (double)height - gap - rectWidth
                                , rectHeight, rectWidth));
            g2d.fill(new Rectangle2D.Double(
                                  (double)x + gap
                                , (double)height - gap
                                , rectWidth, rectHeight));
            // Lower Right Border
            g2d.fill(new Rectangle2D.Double(
                                  (double)width - gap - rectHeight
                                , (double)height - gap - rectWidth
                                , rectHeight, rectWidth));
            g2d.fill(new Rectangle2D.Double(
                                  (double)width - gap - rectWidth
                                , (double)height - gap
                                , rectWidth, rectHeight));
        }
    }

    @Override
    public Insets getBorderInsets(Component c)
    {
        return (getBorderInsets(c, new Insets(gap, gap, gap, gap)));
    }

    @Override
    public Insets getBorderInsets(Component c, Insets insets)
    {
        insets.left = insets.top = insets.right = insets.bottom = gap;
        return insets;
    }

    @Override
    public boolean isBorderOpaque()
    {
        return true;
    }
}

输出：

细而粗线的边框

对于

【讨论】：

..很好。 :) 另见How do I create screenshots?（有关制作出色截图的技巧）。
@AndrewThompson ：我的鼠标表现得很奇怪，似乎是时候更换鼠标了，因为它在被拖动时很少使用。我将链接添加到我的最爱，因为您之前曾指出过我一次，关于同一件事:-)。其余的你是最欢迎和保持微笑:-)
我主要是在想 Alt+PrintScreen 将如何“自动修剪”活动窗口，现在不确定它在长（长）线程中的位置。 ;)
感谢回复，细线边框代码中的g2d.setStroke(new BasicStroke(5));可以在不更改所有代码的情况下更改为粗线。

【解决方案2】：

是的。示例见this answer。

【讨论】：