使用JFrame调整大小来调整Graphics2D对象的大小

Question

我正在制作一个在JFrame的JPanel上绘制有Graphics2D对象的GUI。 当我调整窗口大小时，Graphics2D对象缩小为一个小矩形。 当用户调整窗口大小时，如何设置图形以使用JFrame调整大小？

我尝试使用gridlayout，flowlayout，borderlayout，并确定为gridbaglayout。 这有助于调整btnPanel和JButton的大小，但不适用于Graphics2D对象。

这是我自包含的示例：

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Ellipse2D;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;

public class DrawPanelMain extends JPanel {

    /*
    * Variables used to set the value of preferred height and width
    */
    public static final double version = 0.0;
    JPanel btnPanel = new JPanel();
    JPanel switchPanel = new JPanel();

    DrawEllipses drawEllipses = new DrawEllipses(POINT_LIST);

    public static void main(String[] args) {

        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                initializePointList();
                createAndShowGui();
            }
        });
    }

    public static java.util.List<Point> POINT_LIST = new ArrayList<>();

    /*
    * This loop will initialize POINT_LIST with the set of points for drawing the ellipses.
    * The for each loop initializes points for the top row and the second for loop draws the
    * right triangle.
    */
    public static void initializePointList() {

        int ellipsePointsYCoordinate[] = {140, 200, 260, 320, 380, 440, 500, 560, 620};
        int ellipsePointsXCoordinate[] = {140, 200, 260, 320, 380, 440, 500, 560, 620, 680};
        int xx = 80;

        for (int aXt : ellipsePointsXCoordinate) {
            POINT_LIST.add(new Point(aXt, xx));
        }

        for (int i = 0; i < ellipsePointsYCoordinate.length; i++) {
            for (int j = i; j < ellipsePointsYCoordinate.length; j++) {
                POINT_LIST.add(new Point(ellipsePointsXCoordinate[i], ellipsePointsYCoordinate[j]));
            }
        }
    }

    public DrawPanelMain() {

        switchPanel.setBorder(BorderFactory.createLoweredSoftBevelBorder());
        switchPanel.setBackground(Color.DARK_GRAY);
        switchPanel.add(drawEllipses);
        switchPanel.revalidate();

        setLayout(new GridBagLayout());
        GridBagConstraints c = new GridBagConstraints();

        // first column
        c.gridx = 0;
        add(switchPanel, c);

        // second column
        c.gridx = 1;
        add(switchPanel, c);

        // first row
        c.gridy = 0;

        // second row
        c. gridy = 1;
        add(btnPanel, c);

        btnPanel.add(new JButton(new AddSwitchAction("Add Switch Panel")));
    }

    public static void createAndShowGui() {

        JFrame frame = new JFrame("RF Connection Panel " + version);

        frame.setLayout(new BorderLayout());
        frame.add(new DrawPanelMain());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLocationByPlatform(false);
        //frame.setLocationRelativeTo(null);
        frame.pack();
        frame.setVisible(true);
    }

    /*
    * AddSwitchAction will add a new pane to the tabbedPane when the add switch button is clicked
    */
    private class AddSwitchAction extends AbstractAction {
        public AddSwitchAction(String name) {
            super(name);
            int mnemonic = (int) name.charAt(0);
            putValue(MNEMONIC_KEY, mnemonic);
        }

        @Override
        public void actionPerformed(ActionEvent e) {
            String title = "Switch ";
            DrawEllipses tabComponent = new DrawEllipses(POINT_LIST);
            switchPanel.add(title, tabComponent);

        }
    }

}

@SuppressWarnings("serial")
class DrawEllipses extends JPanel {
    private final int PREF_W = 750; //Window width
    private final int PREF_H = 750; //Window height
    private final int OVAL_WIDTH = 30;
    private static final Color INACTIVE_COLOR = Color.RED;
    private static final Color ACTIVE_COLOR = Color.green;
    private java.util.List<Point> points;
    private java.util.List<Ellipse2D> ellipses = new ArrayList<>();
    private Map<Ellipse2D, Color> ellipseColorMap = new HashMap<>();

    /*
     * This method is used to populate "ellipses" with the initialized ellipse2D dimensions
     */
    public DrawEllipses(java.util.List<Point> points) {
        this.points = points;
        for (Point p : points) {
            int x = p.x - OVAL_WIDTH / 2;
            int y = p.y - OVAL_WIDTH / 2;
            int w = OVAL_WIDTH;
            int h = OVAL_WIDTH;
            Ellipse2D ellipse = new Ellipse2D.Double(x, y, w, h);
            ellipses.add(ellipse);
            ellipseColorMap.put(ellipse, INACTIVE_COLOR);
        }

        MyMouseAdapter mListener = new MyMouseAdapter();
        addMouseListener(mListener);
        addMouseMotionListener(mListener);
    }

    /*
     * paintComponent is used to paint the ellipses
     */
    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2 = (Graphics2D) g;
        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                RenderingHints.VALUE_ANTIALIAS_ON);
        for (Ellipse2D ellipse : ellipses) {
            g2.setColor(ellipseColorMap.get(ellipse));
            g2.fill(ellipse);
            g2.setColor(Color.BLACK);
            g2.setStroke(new BasicStroke(2));
            g2.draw(ellipse);
        }

        /*
         * Set the font characteristics, color, and draw the row labels.
         */
        g.setFont(new Font("TimesRoman", Font.BOLD, 18));
        g.setColor(Color.BLACK);

        //Along the top row
        g.drawString("External Port", 10, 50);
        g.drawString("1", 135, 50);
        g.drawString("2", 195, 50);
        g.drawString("3", 255, 50);
        g.drawString("4", 315, 50);
        g.drawString("5", 375, 50);
        g.drawString("6", 435, 50);
        g.drawString("7", 495, 50);
        g.drawString("8", 555, 50);
        g.drawString("9", 615, 50);
        g.drawString("10", 672, 50);

        //Along the Y-axis
        g.drawString("Radio 2", 40, 145);
        g.drawString("3", 90, 205);
        g.drawString("4", 90, 265);
        g.drawString("5", 90, 325);
        g.drawString("6", 90, 385);
        g.drawString("7", 90, 445);
        g.drawString("8", 90, 505);
        g.drawString("9", 90, 565);
        g.drawString("10", 90, 625);

        //Along the X-Axis
        g.drawString("1", 135, 670);
        g.drawString("2", 195, 670);
        g.drawString("3", 255, 670);
        g.drawString("4", 315, 670);
        g.drawString("5", 375, 670);
        g.drawString("6", 435, 670);
        g.drawString("7", 495, 670);
        g.drawString("8", 555, 670);
        g.drawString("9", 615, 670);

        //Draws a 3DRect around the top row of ellipse2D objects
        g2.setColor(Color.lightGray);
        g2.draw3DRect(120, 60, 580, 40, true);
        g2.draw3DRect(121, 61, 578, 38, true);
        g2.draw3DRect(122, 62, 576, 36, true);

    }

    /*
     * MouseAdapter is extended for mousePressed Event that detects if the x, y coordinates
     * of a drawn ellipse are clicked.  If the color is INACTIVE it is changed to ACTIVE and
     * vice versa.
     */
    private class MyMouseAdapter extends MouseAdapter {
        @Override
        /*
         * When mousePressed event occurs, the color is toggled between ACTIVE and INACTIVE
         */
        public void mousePressed(MouseEvent e) {
            Color c;
            for (Ellipse2D ellipse : ellipses) {
                if (ellipse.contains(e.getPoint())) {
                    c = (ellipseColorMap.get(ellipse) == INACTIVE_COLOR) ? ACTIVE_COLOR : INACTIVE_COLOR;
                    ellipseColorMap.put(ellipse, c);
                }
            }
            repaint();
        }
    }

    /*
* This method will set the dimensions of the JFrame equal to the preferred H x W
*/
    @Override
    public Dimension getPreferredSize() {
        if (isPreferredSizeSet()) {
            return super.getPreferredSize();
        }
        return new Dimension(PREF_W, PREF_H);
    }


    /*
     * Used for button click action to change all ellipses to ACTIVE_COLOR
     */
    public void activateAll(){
        for (Ellipse2D ellipse : ellipses){
            ellipseColorMap.put(ellipse, ACTIVE_COLOR);
        }
        repaint();
    }

    /*
     * Used for button click action to change all ellipses to INACTIVE_COLOR
     */
    public void deactivateAll(){
        for (Ellipse2D ellipse : ellipses){
            ellipseColorMap.put(ellipse, INACTIVE_COLOR);
        }
        repaint();
    }
}

Answer 1

该方法将JFrame的尺寸设置为首选的H x W

不，它设置面板的首选大小。 框架的大小将是添加到框架中的所有组件的首选大小，再加上框架装饰（标题栏，边框）。

当我调整窗口大小时，Graphics2D对象缩小为一个小矩形。

GridBagLayout遵循组件的首选大小。 如果没有足够的空间来显示组件，它将缩小为“最小大小”。

您可能需要重写getMinimumSize()方法以等于首选大小。 然后，在这种情况下，如果没有可用空间，则该组件应被截断。

如果要实际绘画缩小，则需要在绘画代码中建立逻辑，以便相对于面板上的可用空间进行绘画。

Answer 2

尝试将2D对象作为ImageIcon的BufferedImage添加到JLabel。 您可以通过以下方式做到这一点：

JLabel label2 = new JLabel(new ImageIcon(//Location of your Image);

或者我认为您也可以添加Graphics2D对象，直接在标签bu中创建它们，我不确定