调整 Java 框架大小时调整组件大小

Question

我在调整GUI大小时遇到了一些问题，希望能够调整GUI中组件的大小。目前，当我改变GUI大小时，组件的大小不会改变，它们仍然保持静态大小。当我调整GUI大小超过显示组件所需的最小大小时，它们就不再显示了。我希望在调整GUI大小时，它们能够按比例缩放并保持一个纵横比。

这是我的GUI代码：

import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.awt.image.ImageObserver;
import java.io.*;
import java.net.*;

import javax.imageio.ImageIO;
import javax.swing.*;
import javax.swing.border.Border;
import javax.swing.text.*;
import javax.swing.text.html.*;

public class DraftGUI implements MouseListener {

private JPanel jpPack;
private JPanel jpCards;
private JPanel jpInfo;
private JPanel jpChat;
private TextField tf;
private StyledDocument doc;
private JTextPane tp;
private JScrollPane sp;

public void mousePressed(MouseEvent e) {
}

public void mouseReleased(MouseEvent e) {
}

public void mouseEntered(MouseEvent e) {
    }

    public void mouseExited(MouseEvent e) {
    }

public void mouseClicked(MouseEvent e) {
    e.getComponent().setVisible(false);
}

private Client client;


public GUI(Client client) throws IOException {

    JFrame frame = new JFrame("Draft");

    //set the size to fullscreen to start
    frame.setSize(Toolkit.getDefaultToolkit().getScreenSize().width, Toolkit.getDefaultToolkit().getScreenSize().height);

    //set the content pane, we'll add everything to it and then add it to the frame
    JPanel contentPane = new JPanel();
    contentPane.setSize(Toolkit.getDefaultToolkit().getScreenSize().width, Toolkit.getDefaultToolkit().getScreenSize().height);
    contentPane.setLayout(new GridBagLayout());

    //creates some panels with some default values for now
    JPanel jpCards = new JPanel(new BorderLayout());
    jpCards.setOpaque(true); //ensures it paints every pixel
    jpCards.setBackground(Color.BLUE);

    JPanel jpInfo = new JPanel();
    jpInfo.setOpaque(true);
    jpInfo.setBackground(Color.GREEN);

    JPanel jpPack = new JPanel(new GridBagLayout());
    jpPack.setOpaque(true);
    jpPack.setBackground(Color.RED);

    //grab some info to make the JTextPane and make it scroll
    this.client = client;
    tf = new TextField();
    doc = new DefaultStyledDocument();
    tp = new JTextPane(doc);
    tp.setEditable(false);
    tf.addActionListener(this.client);
    sp = new JScrollPane(tp);

    //adding the quantities to the chat panel
    JPanel jpChat = new JPanel();
    jpChat.setLayout(new BorderLayout());
    jpChat.add("North", tf);
    jpChat.add("Center", sp);

    //a new GridBagConstraints used to set the properties/location of the panels
    GridBagConstraints c = new GridBagConstraints(); 

    //adding some panels to the content pane
    //set it to start from the top left of the quadrant if it's too small
    c.anchor = GridBagConstraints.FIRST_LINE_START; 
    c.fill = GridBagConstraints.BOTH; //set it to fill both vertically and horizontally
    c.gridx = 0; //set it to quadrant x=0 and
    c.gridy = 0; //set it to quadrant y=0
    c.weightx = 0.7;
    c.weighty = 0.3;
    contentPane.add(jpCards, c);

    c.gridx = 1;
    c.gridy = 0;
    c.weightx = 0.3;
    c.weighty = 0.3;
    contentPane.add(jpInfo, c);

    c.gridx = 0;
    c.gridy = 1;
    c.weightx = 0.7;
    c.weighty = 0.7;
    contentPane.add(jpPack, c);

    c.gridx = 1;
    c.gridy = 1;
    c.weightx = 0.3;
    c.weighty = 0.7;
    contentPane.add(jpChat, c);

    //set some necessary values 
    frame.setContentPane(contentPane);
    frame.setLocationByPlatform(true);
    frame.setVisible(true);

    //This code works for adding an Image
    //need to learn how to specify a path not dependent on the specific users's machine
    //this is not a high priority for now though
    GridBagConstraints d = new GridBagConstraints();
    d.gridx = 0;
    d.gridy = 0;

    ImageLabel imageLabel1 = new ImageLabel("path-to-file");

    imageLabel1.setPreferredSize(new Dimension(223, 310));
    jpPack.add(imageLabel1, d);

    ImageLabel imageLabel2 = new ImageLabel("path-to-file");
    imageLabel2.setPreferredSize(new Dimension(223, 310));
    ImageLabel imageLabel3 = new ImageLabel("path-to-file");
    imageLabel3.setPreferredSize(new Dimension(223, 310));
    d.gridx = 1;
    jpPack.add(imageLabel2, d);
    d.gridy = 1;
    jpPack.add(imageLabel3, d);

    imageLabel1.addMouseListener(this);
    imageLabel2.addMouseListener(this);
    imageLabel3.addMouseListener(this);

    //223, 310 are the aspect values for a card image, width, height
    //these need to be maintained as the GUI size changes

    }

}


class ImageLabel extends JLabel {
   Image image;
   ImageObserver imageObserver; 

   // constructor with filename     
   ImageLabel(String filename) {
      ImageIcon icon = new ImageIcon(filename);
      image = icon.getImage();
      imageObserver = icon.getImageObserver();
   }

   // constructor with icon
   ImageLabel(ImageIcon icon) {
      image = icon.getImage();
      imageObserver = icon.getImageObserver();
   }

   // overload setIcon method
   void setIcon(ImageIcon icon) {
      image = icon.getImage();
      imageObserver = icon.getImageObserver();
   }

   // overload paint()
   public void paint( Graphics g ) {
       super.paint( g );
       g.drawImage(image,  0 , 0 , getWidth() , getHeight() , imageObserver);

   }

}

由于某些原因，框架的组件没有默认的调整大小属性，因此当框架调整大小时，组件不会做出任何响应。我不确定我做错了什么或者漏掉了什么，但显然我漏掉了一些东西。

此外，如果有人知道，ImageLabels周围会占用额外的空间。填充默认设置为0，所以我不确定为什么它们会创建像边框一样的东西。

谢谢。

针对Guillaume的编辑：

我知道如果我想要将其作为独立运行，则需要一个主要函数，它当前是另一个应用程序的一部分，并从其中单独调用。发布它时没有主函数可能不是最好的决定，但无论如何，这不可能是一个大问题。

您的代码删除了实际显示图片的部分。 "path-to-file"应替换为实际的图像文件路径，以便显示图像。当它只是文本时，很难看到实际问题。

当您正确显示图像并尝试调整整个GUI大小时，您会注意到图像不会缩小。它保持其首选大小，并在变小时遇到问题。在我的代码中，当无法显示至少首选大小时，它停止显示图片。在您的代码中，它在缩小时切掉部分图片。

我想要的是实际调整包含图片的JLabel的大小，以便随着GUI的调整而调整图像。对于我的程序，必须相应地缩小图像。用户最终将根据单击图像的功能进行操作，因此仅显示某些图像或其中的部分将不起作用。

请再次尝试您的代码/我的代码，并使用图片重现我遇到的问题，以便我们可以找到正确的解决方案。谢谢。

- Michael Yousef

---

你需要使用一个不同的布局管理器，而不是网格袋布局，因为它会尊重可用的首选大小。我一时想不起来推荐哪个。问题在于如何确定“纵横比”。 - MadProgrammer

请看我的更新答案。 - Guillaume Polet

你和@GuillaumePolet的一个区别是，你主动短路了标签的自我调整大小：一般规则是永远不要调用任何setXXSize方法。话虽如此：图像具有固定大小，如果你想缩放它，你必须自己实现缩放。 - kleopatra

再看一遍，有些问题：a）imageLabel.setIcon（ImageIcon）_不是_覆盖label.setIcon（Icon）b）在swing中，覆盖paintComponent 而不是 paint。 - kleopatra

你解决了吗？随意回答自己的问题。 - Igor L.

Answer 1

1. JFrame.setVisible(true)应该是你调用的最后一行。
2. GridBagLayout可以根据框架大小适应组件的大小，只要您使用weightx/weighty和fill

更新:

1. 忘记设置首选大小，这只会导致GUI问题
2. 如果使用LayoutManager（这是一个非常好的主意），请勿调用setSize()/setBounds()/setLocation()，LayoutManager将覆盖它们
3. 您需要注意调整图像的大小以保持原始图像比例
4. 如果使用weightx/weighty，则还应使用anchor和/或fill
5. 使用frame.pack()正确调整框架大小
6. 使用setExtendedState()来最大化框架

顺便说一句，SSCCE意味着为其他人创建可运行的示例，包括将本地路径更改为在线URL（请参阅下面的示例）。

使用以下代码片段，一切似乎都正常工作：

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.TextField;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.net.MalformedURLException;
import java.net.URL;

import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.SwingUtilities;
import javax.swing.text.DefaultStyledDocument;
import javax.swing.text.StyledDocument;

public class DraftGUI implements MouseListener {

    private static final String IMAGE_URL = "http://images.paramountbusinessjets.com/space/spaceshuttle.jpg";
    private JPanel jpPack;
    private JPanel jpCards;
    private JPanel jpInfo;
    private JPanel jpChat;
    private TextField tf;
    private StyledDocument doc;
    private JTextPane tp;
    private JScrollPane sp;

    @Override
    public void mousePressed(MouseEvent e) {
    }

    @Override
    public void mouseReleased(MouseEvent e) {
    }

    @Override
    public void mouseEntered(MouseEvent e) {
    }

    @Override
    public void mouseExited(MouseEvent e) {
    }

    @Override
    public void mouseClicked(MouseEvent e) {
    }

    public DraftGUI() throws MalformedURLException {

        final JFrame frame = new JFrame("Draft");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        // set the content pane, we'll add everything to it and then add it to the frame
        JPanel contentPane = new JPanel();
        contentPane.setLayout(new GridBagLayout());

        // creates some panels with some default values for now
        JPanel jpCards = new JPanel(new BorderLayout());
        jpCards.setBackground(Color.BLUE);

        JPanel jpInfo = new JPanel();
        jpInfo.setBackground(Color.GREEN);

        JPanel jpPack = new JPanel(new GridBagLayout());
        jpPack.setBackground(Color.RED);

        // grab some info to make the JTextPane and make it scroll
        tf = new TextField();
        doc = new DefaultStyledDocument();
        tp = new JTextPane(doc);
        tp.setEditable(false);
        sp = new JScrollPane(tp);

        // adding the quantities to the chat panel
        JPanel jpChat = new JPanel();
        jpChat.setLayout(new BorderLayout());
        jpChat.add("North", tf);
        jpChat.add("Center", sp);

        // a new GridBagConstraints used to set the properties/location of the panels
        GridBagConstraints c = new GridBagConstraints();

        // adding some panels to the content pane
        // set it to start from the top left of the quadrant if it's too small
        c.anchor = GridBagConstraints.FIRST_LINE_START;
        c.fill = GridBagConstraints.BOTH; // set it to fill both vertically and horizontally
        c.gridx = 0; // set it to quadrant x=0 and
        c.gridy = 0; // set it to quadrant y=0
        c.weightx = 0.7;
        c.weighty = 0.3;
        contentPane.add(jpCards, c);

        c.gridx = 1;
        c.gridy = 0;
        c.weightx = 0.3;
        c.weighty = 0.3;
        contentPane.add(jpInfo, c);

        c.gridx = 0;
        c.gridy = 1;
        c.weightx = 0.7;
        c.weighty = 0.7;
        contentPane.add(jpPack, c);

        c.gridx = 1;
        c.gridy = 1;
        c.weightx = 0.3;
        c.weighty = 0.7;
        contentPane.add(jpChat, c);

        // set some necessary values
        frame.setContentPane(contentPane);
        frame.setLocationByPlatform(true);

        // This code works for adding an Image
        // need to learn how to specify a path not dependent on the specific users's machine
        // this is not a high priority for now though
        GridBagConstraints d = new GridBagConstraints();
        d.weightx = 1.0;
        d.weighty = 1.0;
        d.fill = GridBagConstraints.BOTH;
        d.gridx = 0;
        d.gridy = 0;
        ImageLabel imageLabel1 = new ImageLabel(new ImageIcon(new URL(IMAGE_URL)));
        jpPack.add(imageLabel1, d);
        ImageLabel imageLabel2 = new ImageLabel(new ImageIcon(new URL(IMAGE_URL)));
        d.gridx++;
        jpPack.add(imageLabel2, d);

        ImageLabel imageLabel3 = new ImageLabel(new ImageIcon(new URL(IMAGE_URL)));
        d.gridy++;
        jpPack.add(imageLabel3, d);

        imageLabel1.addMouseListener(this);
        imageLabel2.addMouseListener(this);
        imageLabel3.addMouseListener(this);
        frame.pack();
        // 223, 310 are the aspect values for a card image, width, height
        // these need to be maintained as the GUI size changes
            frame.setExtendedState(frame.getExtendedState() | JFrame.MAXIMIZED_BOTH);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    new DraftGUI();
                } catch (MalformedURLException e) {
                    e.printStackTrace();
                }
            }
        });
    }

    public static class ImageLabel extends JPanel {
        private static int counter = 1;
        private ImageIcon icon;
        private int id = counter++;

        public ImageLabel(ImageIcon icon) {
            super();
            setOpaque(false);
            this.icon = icon;
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(icon.getIconWidth(), icon.getIconHeight());
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            double zoom = Math.min((double) getWidth() / icon.getIconWidth(), (double) getHeight() / icon.getIconHeight());
            int width = (int) (zoom * icon.getIconWidth());
            int height = (int) (zoom * icon.getIconHeight());
            g.drawImage(icon.getImage(), (getWidth() - width) / 2, (getHeight() - height) / 2, width, height, this);
            g.setFont(g.getFont().deriveFont(36.0f));
            g.drawString(String.valueOf(id), getWidth() / 2, getHeight() / 2);
        }
    }
}

- Guillaume Polet

---

我尝试了这段代码，但它没有起作用。据我所知，它并没有做任何与我已有的代码不同的事情。重量和填充属性已经设置好了，所以你所做的只是添加了一个setVisible和一个main（这是不必要的，我已经以其他方式调用它了）。你还删除了我添加的ImageLabel代码，以使图片自适应面板大小。还有其他想法吗？ - Michael Yousef

@MichaelYousef 对我来说它是有效的。我删除了所有不相关的部分并添加了一个main（这是基本的！），实际上是你的工作的一部分：只显示必要的内容并提供一个“可运行”的示例（请参见SSCCE）。如果对你不起作用，请重点解释哪些部分不起作用以及你期望什么。 - Guillaume Polet

我已经更新了原始帖子以反映我所需的内容，因为我没有足够的空间在这里放置它。 - Michael Yousef

非常感谢Guillaume，代码运行得非常好。我仍然需要做一些最大和最小尺寸的调整，但这不应该太难。看起来我们之前只是有点走错了方向。它可以很好地调整大小，我感到非常兴奋。再次感谢。 - Michael Yousef

Answer 2

我建议使用这种方法来调整窗口的大小。

JPanel jPanel = new JPanel(new BorderLayout()); // Create a panel that contains the elements you want to resize, in this example I use BorderLayout as the layout manager
jPanel.add(somePanel, BorderLayout.NORTH);
        // this will resize the con
        this.addComponentListener(new ComponentAdapter() {
            @Override
            public void componentResized(ComponentEvent e) {
                somePanel.setSize(e.getComponent().getSize());
                jPanel.paintComponents(getGraphics());
            }
        });

- Ilan Granot