带有miglayout和嵌套面板的摆动布局

Question

我有一个使用SwingLayout的Swing程序。Swing组件的结构如下所示。

JFrame
    JPanel (Cardlayout)
        JPanel (Miglayout) - Main panel
            Jpanel (Flowlayout) - Checkbox Panel
            JPanel (Flowlayout) - Option Panel

我现在的问题是，我不知道如何防止复选框面板增长。我不希望它"推"出它在右边的栏。我希望Wraplayout（在选项面板上运行良好）在复选框面板变得太大时包装它的内容。

这是Eclipse内部Windowsbuilder GUI中的视图。带有标签"sites"的面板是复选框面板。复选框面板右侧是选项面板。包含这两者的大面板是主面板。https://i.stack.imgur.com/K7Gp1.png

当我添加太多复选框时，就会发生这种情况https://i.stack.imgur.com/0aJM7.png

我的主要问题是，我不明白为什么当我在站点面板中添加新的复选框时，在主面板中第一列的列约束上设置"grow 0"并不能阻止它的增长（站点面板可以有任意数量的复选框）。

这是我的主面板miglayout。

mainPanel.setLayout(new MigLayout("", "[][grow]", "[][][][][][][][grow]"));

以下是我添加复选框面板时的组件限制

siteCheckBoxPanel = new JPanel();
mainPanel.add(siteCheckBoxPanel, "cell 0 0,alignx left,gapx 0px,aligny center");
siteCheckBoxPanel.setLayout(new FlowLayout(FlowLayout.CENTER, 5, 5));

我也尝试过不使用流布局，但这并不能解决任何问题。你能提供的任何见解都会很棒！如果人们有疑问，我也很乐意提供更多信息。仅供参考，我还尝试过在复选框面板所在单元格的列和行约束上"增长0"。

这是SSCCE。你可以在下面找到来源。您唯一需要的依赖项是miglayout。您可以单击按钮添加复选框。

https://dl.dropbox.com/u/20614368/Test.java

import java.awt.CardLayout;
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.border.EmptyBorder;
import net.miginfocom.swing.MigLayout;

public class Test extends JFrame {

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            private Test frame;
            public void run() {
                try {
                    frame = new Test();
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }
    private JPanel contentPane;
    private JPanel mainPanel;
    private JPanel optionPanel;
    private JButton btnUploadImages;
    private JLabel thumbnailLabel;
    private JTextArea textArea;
    private JPanel checkboxPanel;
    private final Action action = new SwingAction();
    /**
     * Create the frame.
     */
    public Test() {
        setVisible(true);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds(100, 100, 1098, 846);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        setContentPane(contentPane);
        contentPane.setLayout(new CardLayout(0, 0));
        mainPanel = new JPanel();
        mainPanel.setName("");
        contentPane.add(mainPanel, "name_329556913535654");
        mainPanel.setLayout(new MigLayout("", "[][grow]", "[][][][][][][][grow]"));

        JLabel lblPicture = new JLabel("Picture");
        mainPanel.add(lblPicture, "cell 0 1");
        optionPanel = new JPanel();
        optionPanel.setBackground(Color.red);
        mainPanel.add(optionPanel, "cell 1 0 1 5,grow");
        btnUploadImages = new JButton("Upload Images");
        btnUploadImages.setAction(action);
        thumbnailLabel = new JLabel("");
        mainPanel.add(thumbnailLabel, "cell 0 4");
        textArea = new JTextArea();
        mainPanel.add(btnUploadImages, "cell 0 6");
        checkboxPanel = new JPanel();
        checkboxPanel.setBackground(Color.green);
        mainPanel.add(checkboxPanel, "flowx,cell 0 0");
        JLabel lblSites = new JLabel("Sites");
        checkboxPanel.add(lblSites);

    }
    private class SwingAction extends AbstractAction {
        public SwingAction() {
            putValue(NAME, "Add checkbox");
            putValue(SHORT_DESCRIPTION, "Some short description");
        }
        public void actionPerformed(ActionEvent e) {
            JCheckBox box = new JCheckBox();
            box.setName("Foobar!");
            checkboxPanel.add(box);
            contentPane.validate();
            contentPane.repaint();
        }
    }
}

Answer 1

理论上，如果您告诉布局，您的设置应该如您所期望的那样工作

• 通过将最大值设置为百分比，使第一列不超过最大值
• 通过在列约束中将最小值设置为pref，使optionPanel列不收缩到其pref下

列约束示例：

// first column - restrict max  
"[grow, fill, n:pref:30%]" +
// second column - restrict min 
"[grow, pref:pref:n]" 

实际上，无论受到什么限制，我都无法使FlowLayout和MigLayout很好地配合使用：甚至初始布局也被破坏了（例如，optionPanel被推离了框架宽度）。用Rob的WrapLayout替换FlowLayout看起来更好，但并不完全是最优的，因为盒子之间没有完全对齐。

/*
 * Created on 12.09.2012
 *
 */
package layout;
import java.awt.CardLayout;
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.border.EmptyBorder;
import net.miginfocom.swing.MigLayout;
public class MigLayoutNested extends JFrame {

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            private MigLayoutNested frame;
            public void run() {
                try {
                    frame = new MigLayoutNested();
                    frame.pack();
//                    frame.setSize(frame.getWidth(), frame.getHeight()* 2);
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }
    private JPanel contentPane;
    private JPanel mainPanel;
    private JPanel optionPanel;
    private JButton btnUploadImages;
    private JLabel thumbnailLabel;
    private JTextArea textArea;
    private JPanel checkboxPanel;
    private final Action action = new SwingAction();
    /**
     * Create the frame.
     */
    public MigLayoutNested() {
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        contentPane = (JPanel) getContentPane(); //new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        contentPane.setLayout(new CardLayout(0, 0));
        mainPanel = new JPanel();
        contentPane.add(mainPanel, "name_329556913535654");
        mainPanel.setLayout(new MigLayout("debug", 
                "[grow, fill][grow, pref:pref:n]" 
               , "[grow, fill][][][][][][][grow]"
                ));
        // stand-in to simulate a row-spanning all-growing component
        optionPanel = new JPanel();
        ((FlowLayout) optionPanel.getLayout()).setAlignment(JLabel.RIGHT);
        JLabel option = new JLabel("just some label so we see the trailing corner, long enough");
        optionPanel.add(option);
        optionPanel.setBackground(Color.YELLOW);
        mainPanel.add(optionPanel, "cell 1 0 1 5, grow");
        // the panel to dynamically add components to  
        // expected behaviour is to wrap on revalidate if needed
        // not working with FlowLayout, but looks half-way fine
        // with Rob's WrapLayout
        checkboxPanel = new JPanel(new WrapLayout()); 
        checkboxPanel.setBackground(Color.green);
        JLabel lblSites = new JLabel("Sites");
        checkboxPanel.add(lblSites);
        mainPanel.add(checkboxPanel, "cell 0 0");
        JLabel lblPicture = new JLabel("Picture");
        mainPanel.add(lblPicture, "cell 0 1");
        thumbnailLabel = new JLabel("thumb");
        mainPanel.add(thumbnailLabel, "cell 0 3");
        textArea = new JTextArea(10, 10);
        mainPanel.add(textArea, "cell 0 4");
        btnUploadImages = new JButton("Upload Images");
        btnUploadImages.setAction(action);
        mainPanel.add(btnUploadImages, "cell 0 6");

    }
    private class SwingAction extends AbstractAction {
        public SwingAction() {
            putValue(NAME, "Add checkbox");
            putValue(SHORT_DESCRIPTION, "Some short description");
        }
        @Override
        public void actionPerformed(ActionEvent e) {
            JCheckBox box = new JCheckBox();
            box.setName("Foobar!");
            checkboxPanel.add(box);
            checkboxPanel.revalidate();
        }
    }
}