设置 JComboBox PopupMenu 的大小答案

【问题标题】：Set Size of JComboBox PopupMenu设置 JComboBox PopupMenu 的大小
【发布时间】：2011-11-28 01:47:13
【问题描述】：

我正在编写一个扩展 JComboBox 的自定义组件。我的问题是，如果我添加或删除一个项目，PopupMenu 不会实现它的大小。所以有例如列表中有 2 个项目，但如果之前有 4 个，我在 PopupMenu 中也有 2 个“空”项目。

我发现的唯一解决方法是（在 JIntelligentComboBox.java 第 213 行）

this.setPopupVisible(false); this.setPopupVisible(true);

但结果将是一个闪烁的 PopupMenu :-(

那么我还能做些什么来刷新/重新绘制 PopupMenu 而不会闪烁？

用于测试：the component 和一点点test programm
要生成我的问题，您可以例如：

键入“e”
按“返回”
输入“m”

提前致谢

编辑：我的目标是一个组合框，例如Firefox 或 Chrome 中的地址栏，我想显示包含键入字符的 PopupMenu 的所有项目。

cboxtester.java：

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;

import javax.swing.DefaultComboBoxModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.plaf.basic.BasicComboBoxRenderer;


public class cboxtester extends JFrame {

    private DefaultComboBoxModel dcm = new DefaultComboBoxModel(new Object[][] {new Object[] {"Mittagessen", "", 0}, 
                                                                                new Object[] {"Essen", "", 0}, 
                                                                                new Object[] {"Frühstück", "", 0}, 
                                                                                new Object[] {"Abendessen", "", 0}});

    private JIntelligentComboBox icb = new JIntelligentComboBox(dcm);

    private cboxtester(){
        this.add(icb, BorderLayout.CENTER);

        this.add(new JButton("bla"), BorderLayout.EAST);

        this.pack();
        this.setVisible(true);
        this.setDefaultCloseOperation(EXIT_ON_CLOSE);
    }

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        cboxtester cbt = new cboxtester();
    }

}

JIntelligentComboBox.java:

import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.ArrayList;
import java.util.Vector;

import javax.swing.ComboBoxEditor;
import javax.swing.ComboBoxModel;
import javax.swing.DefaultListCellRenderer;
import javax.swing.DefaultRowSorter;
import javax.swing.JComboBox;
import javax.swing.JList;
import javax.swing.JTextField;
import javax.swing.ListCellRenderer;
import javax.swing.MutableComboBoxModel;
import javax.swing.border.Border;
import javax.swing.border.EmptyBorder;
import javax.swing.event.PopupMenuEvent;
import javax.swing.event.PopupMenuListener;
import javax.swing.plaf.basic.BasicComboBoxEditor;
import javax.swing.plaf.basic.BasicComboBoxRenderer;
import javax.swing.plaf.metal.MetalComboBoxEditor;


public class JIntelligentComboBox extends JComboBox {

    private ArrayList<Object> itemBackup = new ArrayList<Object>();

    /**  Initisiert die JIntelligentComboBox */
    private void init(){

        class searchComboBoxEditor extends BasicComboBoxEditor {
            public searchComboBoxEditor(){
                super();
            }

            @Override
            public void setItem(Object anObject){
                if (anObject == null) {
                    super.setItem(anObject);
                } else {
                    Object[] o = (Object[]) anObject;
                    super.setItem(o[0]);
                }
            }

            @Override
            public Object getItem(){
                return new Object[]{super.getItem(), super.getItem(), 0};
            }
        }

        this.setEditor(new searchComboBoxEditor());

        this.setEditable(true);

        class searchRenderer extends BasicComboBoxRenderer {

            public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus){
                if (index == 0) {
                    setText("");
                    this.setPreferredSize(new Dimension(1, 1));
                    return this;
                }

                this.setPreferredSize(new Dimension(160, 17));

                if (index == list.getModel().getSize() - 1) {
                    this.setBorder(new EmptyBorder(0, 3, 1, 3));
                } else {
                    this.setBorder(new EmptyBorder(0, 3, 0, 3));
                }

                Object[] v = (Object[]) value;
                //System.out.println(v[0]);
                this.setFont(new Font("Arial", Font.PLAIN, 12));
                this.setBackground(Color.white);

                String s = (String) v[0];
                String lowerS = s.toLowerCase();
                String sf = (String) v[1];
                String lowerSf = sf.toLowerCase();
                ArrayList<String> notMatching = new ArrayList<String>();

                if (!sf.equals("")){
                    int fs = -1;
                    int lastFs = 0;
                    while ((fs = lowerS.indexOf((String) lowerSf, (lastFs == 0) ? -1 : lastFs)) > -1) {
                        notMatching.add(s.substring(lastFs, fs));
                        lastFs = fs + sf.length();
                        //System.out.println(fs+sf.length());
                    }
                    notMatching.add(s.substring(lastFs));
                    //System.out.println(notMatching);
                }

                String html = "";

                if (notMatching.size() > 1) {
                    html = notMatching.get(0);
                    int start = html.length();
                    int sfl = sf.length();
                    for (int i = 1; i < notMatching.size(); i++) {
                        String t = notMatching.get(i);
                        html += "<b style=\"color: black;\">" + s.substring(start, start + sfl) + "</b>" + t;
                        start += sfl + t.length();
                    }
                }

                System.out.println(index + html);

                this.setText("<html><head></head><body style=\"color: gray;\">" + html + "</body></head>");
                return this;
            }

        }  

        this.setRenderer(new searchRenderer());

        // leeres Element oben einfügen
        int size = this.getModel().getSize();
        Object[] tmp = new Object[this.getModel().getSize()];

        for (int i = 0; i < size; i++) {
            tmp[i] = this.getModel().getElementAt(i);
            itemBackup.add(tmp[i]);
        }

        this.removeAllItems();

        this.getModel().addElement(new Object[]{"", "", 0});
        for (int i = 0; i < tmp.length; i++) {
            this.getModel().addElement(tmp[i]);
        }

        // keylistener hinzufügen
        this.getEditor().getEditorComponent().addKeyListener(new KeyListener() {

            @Override
            public void keyPressed(KeyEvent e) {
                // TODO Auto-generated method stub
            }

            @Override
            public void keyReleased(KeyEvent e) {
                // TODO Auto-generated method stub
                searchAndListEntries(((JTextField)JIntelligentComboBox.this.getEditor().getEditorComponent()).getText());
                //System.out.println(((JTextField)JIntelligentComboBox.this.getEditor().getEditorComponent()).getText());
            }

            @Override
            public void keyTyped(KeyEvent e) {
                // TODO Auto-generated method stub
            }
        });
    }

    public JIntelligentComboBox(){
        super();
    }

    public JIntelligentComboBox(MutableComboBoxModel aModel){
        super(aModel);
        init();
    }

    public JIntelligentComboBox(Object[] items){
        super(items);
        init();
    }

    public JIntelligentComboBox(Vector<?> items){
        super(items);
        init();
    }

    @Override
    public MutableComboBoxModel getModel(){
        return (MutableComboBoxModel) super.getModel();
    }

    private void searchAndListEntries(Object searchFor){        
        ArrayList<Object> found = new ArrayList<Object>();

        //System.out.println("sf: "+searchFor);

        for (int i = 0; i < this.itemBackup.size(); i++) {
            Object tmp = this.itemBackup.get(i);
            if (tmp == null || searchFor == null) continue;

            Object[] o = (Object[]) tmp;
            String s = (String) o[0];
            if (s.matches("(?i).*" + searchFor + ".*")){
                found.add(new Object[]{((Object[])tmp)[0], searchFor, ((Object[])tmp)[2]});
            }
        }

        this.removeAllItems();          

        this.getModel().addElement(new Object[] {searchFor, searchFor, 0});

        for (int i = 0; i < found.size(); i++) {
            this.getModel().addElement(found.get(i));
        }

        this.setPopupVisible(true);     
    }



}

【问题讨论】：

在论坛中发布您的SSCCE 代码，而不是使用指向其他网站的链接。
请学习java命名约定并遵守它们

标签： java swing jcombobox popupmenu

【解决方案1】：

在扩展 AbstractListModel & 的 ComboboxModel 中使用 Vector 数组时遇到了同样的问题实现 MutableComboBoxModel。使用 setMaximumRowCount 解决：

遍历数据库值并将它们保存到 public ArrayList listInCombobox = new ArrayList();
myComboBox.setMaximumRowCount(listInCombobox.size());
在 myComboBox MouseListener (mousePressed) 中执行上述操作。

【讨论】：

【解决方案2】：

我在下面修改了你的sscce，我注意到了一些事情：

您观察到的异常在使用 apple.laf.AquaComboBoxUI 时并不明显。特别是，输入和删除文本会按预期增长和缩小列表。您可以在您的平台上尝试修改后的代码。
为了方便起见，我从KeyListener 切换到KeyAdapter，但这不是解决方案。您可能应该使用DocumentListener。它不能在使用时变异，就像你现在正在做的那样，所以我没有进一步追求。
始终在 event dispatch thread 上构建 GUI。
硬编码的尺寸和新颖的字体很少在其他外观实现中看起来正确。我只是删除了你的以显示外观。
您的构造函数在构造父模型后修改模型，因此结果取决于实例化的顺序。单独的模型可能更容易管理。

更新：添加了验证@camickr 的solution 的代码。

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Window;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.util.ArrayList;
import java.util.List;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JTextField;
import javax.swing.MutableComboBoxModel;
import javax.swing.SwingUtilities;
import javax.swing.plaf.basic.BasicComboBoxEditor;
import javax.swing.plaf.basic.BasicComboBoxRenderer;
import javax.swing.plaf.basic.BasicComboPopup;

public class CBoxTest extends JFrame {

    private CBoxTest() {
        DefaultComboBoxModel dcm = new DefaultComboBoxModel();
        StringBuilder s = new StringBuilder();
        for (char i = 'a'; i < 'm'; i++) {
            s.append(i);
            dcm.addElement(new Object[]{s.toString(), "", 0});
        }
        JIntelligentComboBox icb = new JIntelligentComboBox(dcm);
        this.setDefaultCloseOperation(EXIT_ON_CLOSE);
        this.add(icb, BorderLayout.CENTER);
        this.add(new JButton("Button"), BorderLayout.EAST);
        this.pack();
        this.setLocationRelativeTo(null);
        this.setVisible(true);
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                CBoxTest cbt = new CBoxTest();
            }
        });
    }

    class JIntelligentComboBox extends JComboBox {

        private List<Object> itemBackup = new ArrayList<Object>();

        public JIntelligentComboBox(MutableComboBoxModel aModel) {
            super(aModel);
            init();
        }

        private void init() {
            this.setRenderer(new searchRenderer());
            this.setEditor(new searchComboBoxEditor());
            this.setEditable(true);
            int size = this.getModel().getSize();
            Object[] tmp = new Object[this.getModel().getSize()];
            for (int i = 0; i < size; i++) {
                tmp[i] = this.getModel().getElementAt(i);
                itemBackup.add(tmp[i]);
            }
            this.removeAllItems();
            this.getModel().addElement(new Object[]{"", "", 0});
            for (int i = 0; i < tmp.length; i++) {
                this.getModel().addElement(tmp[i]);
            }
            final JTextField jtf = (JTextField) this.getEditor().getEditorComponent();
            jtf.addKeyListener(new KeyAdapter() {

                @Override
                public void keyReleased(KeyEvent e) {
                    searchAndListEntries(jtf.getText());
                }
            });
        }

        @Override
        public MutableComboBoxModel getModel() {
            return (MutableComboBoxModel) super.getModel();
        }

        private void searchAndListEntries(Object searchFor) {
            List<Object> found = new ArrayList<Object>();
            for (int i = 0; i < this.itemBackup.size(); i++) {
                Object tmp = this.itemBackup.get(i);
                if (tmp == null || searchFor == null) {
                    continue;
                }
                Object[] o = (Object[]) tmp;
                String s = (String) o[0];
                if (s.matches("(?i).*" + searchFor + ".*")) {
                    found.add(new Object[]{
                            ((Object[]) tmp)[0], searchFor, ((Object[]) tmp)[2]
                        });
                }
            }
            this.removeAllItems();
            this.getModel().addElement(new Object[]{searchFor, searchFor, 0});
            for (int i = 0; i < found.size(); i++) {
                this.getModel().addElement(found.get(i));
            }
            this.setPopupVisible(true);
            // https://stackoverflow.com/questions/7605995
            BasicComboPopup popup =
                (BasicComboPopup) this.getAccessibleContext().getAccessibleChild(0);
            Window popupWindow = SwingUtilities.windowForComponent(popup);
            Window comboWindow = SwingUtilities.windowForComponent(this);

            if (comboWindow.equals(popupWindow)) {
                Component c = popup.getParent();
                Dimension d = c.getPreferredSize();
                c.setSize(d);
            } else {
                popupWindow.pack();
            }
        }

        class searchRenderer extends BasicComboBoxRenderer {

            @Override
            public Component getListCellRendererComponent(JList list,
                Object value, int index, boolean isSelected, boolean cellHasFocus) {
                if (index == 0) {
                    setText("");
                    return this;
                }
                Object[] v = (Object[]) value;
                String s = (String) v[0];
                String lowerS = s.toLowerCase();
                String sf = (String) v[1];
                String lowerSf = sf.toLowerCase();
                List<String> notMatching = new ArrayList<String>();

                if (!sf.equals("")) {
                    int fs = -1;
                    int lastFs = 0;
                    while ((fs = lowerS.indexOf(lowerSf, (lastFs == 0) ? -1 : lastFs)) > -1) {
                        notMatching.add(s.substring(lastFs, fs));
                        lastFs = fs + sf.length();
                    }
                    notMatching.add(s.substring(lastFs));
                }
                String html = "";
                if (notMatching.size() > 1) {
                    html = notMatching.get(0);
                    int start = html.length();
                    int sfl = sf.length();
                    for (int i = 1; i < notMatching.size(); i++) {
                        String t = notMatching.get(i);
                        html += "<b style=\"color: black;\">"
                            + s.substring(start, start + sfl) + "</b>" + t;
                        start += sfl + t.length();
                    }
                }
                this.setText("<html><head></head><body style=\"color: gray;\">"
                    + html + "</body></head>");
                return this;
            }
        }

        class searchComboBoxEditor extends BasicComboBoxEditor {

            public searchComboBoxEditor() {
                super();
            }

            @Override
            public void setItem(Object anObject) {
                if (anObject == null) {
                    super.setItem(anObject);
                } else {
                    Object[] o = (Object[]) anObject;
                    super.setItem(o[0]);
                }
            }

            @Override
            public Object getItem() {
                return new Object[]{super.getItem(), super.getItem(), 0};
            }
        }
    }
}

【讨论】：

【解决方案3】：

以下解决方案的基础是每次调用searchAndListRoutine 时调整弹出窗口的大小。您需要考虑到，当弹出窗口显示在父框架的边界之外时，弹出窗口可以显示在自己的窗口中，也可以显示在父框架的分层窗格中：

import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
import java.util.Vector;

import javax.swing.*;
import javax.swing.border.*;
import javax.swing.event.*;
import javax.swing.plaf.basic.*;
import javax.swing.plaf.metal.*;
import javax.swing.plaf.basic.*;


public class JIntelligentComboBox extends JComboBox {

    private ArrayList<Object> itemBackup = new ArrayList<Object>();

    /**  Initisiert die JIntelligentComboBox */
    private void init(){

        class searchComboBoxEditor extends BasicComboBoxEditor {
            public searchComboBoxEditor(){
                super();
            }

            @Override
            public void setItem(Object anObject){
                if (anObject == null) {
                    super.setItem(anObject);
                } else {
                    Object[] o = (Object[]) anObject;
                    super.setItem(o[0]);
                }
            }

            @Override
            public Object getItem(){
                return new Object[]{super.getItem(), super.getItem(), 0};
            }
        }

        this.setEditor(new searchComboBoxEditor()); 

        this.setEditable(true); 

        class searchRenderer extends BasicComboBoxRenderer { 

            public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus){
                if (index == 0) { 
                    setText(""); 
                    this.setPreferredSize(new Dimension(1, 1)); 
                    return this; 
                } 

                this.setPreferredSize(new Dimension(160, 17)); 

                if (index == list.getModel().getSize() - 1) { 
                    this.setBorder(new EmptyBorder(0, 3, 1, 3)); 
                } else { 
                    this.setBorder(new EmptyBorder(0, 3, 0, 3)); 
                }

                Object[] v = (Object[]) value; 
                //System.out.println(v[0]);
                this.setFont(new Font("Arial", Font.PLAIN, 12));
                this.setBackground(Color.white);

                String s = (String) v[0];
                String lowerS = s.toLowerCase();
                String sf = (String) v[1];
                String lowerSf = sf.toLowerCase();
                ArrayList<String> notMatching = new ArrayList<String>();

                if (!sf.equals("")){
                    int fs = -1;
                    int lastFs = 0;
                    while ((fs = lowerS.indexOf((String) lowerSf, (lastFs == 0) ? -1 : lastFs)) > -1) {
                        notMatching.add(s.substring(lastFs, fs));
                        lastFs = fs + sf.length();
                        //System.out.println(fs+sf.length());
                    }
                    notMatching.add(s.substring(lastFs));
                    //System.out.println(notMatching);
                }

                String html = "";

                if (notMatching.size() > 1) {
                    html = notMatching.get(0);
                    int start = html.length();
                    int sfl = sf.length();
                    for (int i = 1; i < notMatching.size(); i++) {
                        String t = notMatching.get(i);
                        html += "<b style=\"color: black;\">" + s.substring(start, start + sfl) + "</b>" + t;
                        start += sfl + t.length();
                    }
                }

                this.setText("<html><head></head><body style=\"color: gray;\">" + html + "</body></head>");
                return this;
            }

        }

        this.setRenderer(new searchRenderer());

        //
        int size = this.getModel().getSize();
        Object[] tmp = new Object[this.getModel().getSize()];

        for (int i = 0; i < size; i++) {
            tmp[i] = this.getModel().getElementAt(i);
            itemBackup.add(tmp[i]);
        }

        this.removeAllItems();

        this.getModel().addElement(new Object[]{"", "", 0});
        for (int i = 0; i < tmp.length; i++) {
            this.getModel().addElement(tmp[i]);
        }

        //
        this.getEditor().getEditorComponent().addKeyListener(new KeyListener() { 

            @Override 
            public void keyPressed(KeyEvent e) { 
                // TODO Auto-generated method stub 
            } 

            @Override 
            public void keyReleased(KeyEvent e) { 
                // TODO Auto-generated method stub 
                searchAndListEntries(((JTextField)JIntelligentComboBox.this.getEditor().getEditorComponent()).getText()); 
                //System.out.println(((JTextField)JIntelligentComboBox.this.getEditor().getEditorComponent()).getText()); 
            } 

            @Override 
            public void keyTyped(KeyEvent e) {
                // TODO Auto-generated method stub 
            }
        });
    }

    public JIntelligentComboBox(){ 
        super(); 
    } 

    public JIntelligentComboBox(MutableComboBoxModel aModel){
        super(aModel); 
        init(); 
    } 

    public JIntelligentComboBox(Object[] items){
        super(items);
        init();
    }

    public JIntelligentComboBox(Vector<?> items){
        super(items);
        init();
    }

    @Override
    public MutableComboBoxModel getModel(){
        return (MutableComboBoxModel) super.getModel();
    }

    private void searchAndListEntries(Object searchFor){
        ArrayList<Object> found = new ArrayList<Object>();

        //System.out.println("sf: "+searchFor);

        for (int i = 0; i < this.itemBackup.size(); i++) {
            Object tmp = this.itemBackup.get(i);
            if (tmp == null || searchFor == null) continue;

            Object[] o = (Object[]) tmp;
            String s = (String) o[0];
            if (s.matches("(?i).*" + searchFor + ".*")){
                found.add(new Object[]{((Object[])tmp)[0], searchFor, ((Object[])tmp)[2]});
            }
        }

        this.removeAllItems();

        this.getModel().addElement(new Object[] {searchFor, searchFor, 0});

        for (int i = 0; i < found.size(); i++) {
            this.getModel().addElement(found.get(i));
        }

        //this.setPopupVisible(true);
        int size = this.getModel().getSize() - 1;

        System.out.println("Elements: " + size);

        if (size == 0)
        {
            this.setPopupVisible( false );
            return;
        }

        this.setPopupVisible(true);

        BasicComboPopup popup =
            (BasicComboPopup)this.getAccessibleContext().getAccessibleChild(0);
        Window popupWindow = SwingUtilities.windowForComponent(popup);
        Window comboWindow = SwingUtilities.windowForComponent(this);

        if (comboWindow.equals(popupWindow))
        {
            Component c = popup.getParent();
            Dimension d = c.getPreferredSize();
            c.setSize(d);
        }
        else
        {
            popupWindow.pack();
        }
    }
}

一个问题是，当组合框字段为空时，模型包含 4 个条目。我猜你的匹配逻辑有问题。

【讨论】：

+1 我在com.apple.laf.AquaLookAndFeel 上看到了类似的结果。
请学习 java 命名约定并遵守它们（无法抗拒:-)
就是这样！！非常感谢 :-) 我的计划也是访问 PopupMenu，但我不知道该怎么做@kleopatra 你有命名约定的链接吗？我通常用 c++ 或 delphi/pascal 编程，而且我对 java 比较陌生，这可能会导致一些问题 ;-)

【解决方案4】：

没有测试你的代码，

请对 Renderer here 和 AutoComplete JComboBox here 的内容提出建议

【讨论】：

好吧，我都检查了它们，但它们没有帮助“渲染器”可能是一个即将出现的问题，如果我用更多条目测试我的盒子;-) 另一个不使用PopupMenu 永久...我尝试在 Firefox 或 chrome 中获得像地址栏这样的组合框（没有网络搜索选项 ;-)）
+1 这是另一个JComboBox variation。
这种变化非常好，但不是我真正需要的，因为这个版本似乎不支持可编辑的组合框，这是一种避免我的弹出刷新问题的方法，但不是我想要的想。此外，如果您键入“ball”，则不支持列出“football”。但无论如何谢谢......我现在要睡觉了，请不要指望我在下一个我们的答复内;-)

【解决方案5】：

你试过了吗？

http://download.oracle.com/javase/6/docs/api/javax/swing/JComboBox.html#updateUI()

【讨论】：

是的，但结果是，ComboBox 失去了焦点，PopupMenu 崩溃了 -.-
-1 任何使用 updateUI() 方法的建议几乎肯定是错误的。 LAF 没有改变。