我正在寻找一种解决方案，该解决方案是我希望根据键入内容在JComboBox中自动选择项目。我正在使用以下代码：
package autocompletion;
/**
*
* @author admin
*/
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.ComboBoxEditor;
import javax.swing.ComboBoxModel;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.JTextComponent;
import javax.swing.text.PlainDocument;
public class AutoCompletion extends PlainDocument {
JComboBox comboBox;
ComboBoxModel model;
JTextComponent editor;
// flag to indicate if setSelectedItem has been called
// subsequent calls to remove/insertString should be ignored
boolean selecting=false;
boolean hidePopupOnFocusLoss;
boolean hitBackspace=false;
boolean hitBackspaceOnSelection;
KeyListener editorKeyListener;
FocusListener editorFocusListener;
public AutoCompletion(final JComboBox comboBox) {
this.comboBox = comboBox;
model = comboBox.getModel();
editor = (JTextComponent) comboBox.getEditor().getEditorComponent();
editor.setDocument(this);
comboBox.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (!selecting) highlightCompletedText(0);
}
});
editor.addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent e) {
if (comboBox.isDisplayable()) comboBox.setPopupVisible(true);
}
});
// Bug 5100422 on Java 1.5: Editable JComboBox won't hide popup when tabbing out
hidePopupOnFocusLoss=System.getProperty("java.version").startsWith("1.5");
// Highlight whole text when gaining focus
editor.addFocusListener(new FocusAdapter() {
public void focusGained(FocusEvent e) {
highlightCompletedText(0);
}
public void focusLost(FocusEvent e) {
// Workaround for Bug 5100422 - Hide Popup on focus loss
if (hidePopupOnFocusLoss) comboBox.setPopupVisible(false);
}
});
// Handle initially selected object
Object selected = comboBox.getSelectedItem();
if (selected!=null) setText(selected.toString());
highlightCompletedText(0);
}
public static void enable(JComboBox comboBox) {
// has to be editable
comboBox.setEditable(true);
// change the editor's document
new AutoCompletion(comboBox);
}
void configureEditor(ComboBoxEditor newEditor) {
if (editor != null) {
editor.removeKeyListener(editorKeyListener);
editor.removeFocusListener(editorFocusListener);
}
if (newEditor != null) {
editor = (JTextComponent) newEditor.getEditorComponent();
editor.addKeyListener(editorKeyListener);
editor.addFocusListener(editorFocusListener);
editor.setDocument(this);
}
}
public void remove(int offs, int len) throws BadLocationException {
// return immediately when selecting an item
if (selecting) return;
//System.out.println("remove " + len + " at " + offs);
super.remove(offs, len);
}
public void insertString(int offs, String str, AttributeSet a) throws BadLocationException {
// return immediately when selecting an item
if (selecting) return;
// insert the string into the document
super.insertString(offs, str, a);
// lookup and select a matching item
Object item = lookupItem(getText(0, getLength()));
if (item != null) {
setSelectedItem(item);
} else {
// keep old item selected if there is no match
item = comboBox.getSelectedItem();
// imitate no insert (later on offs will be incremented by str.length(): selection won't move forward)
offs = offs-str.length();
// provide feedback to the user that his input has been received but can not be accepted
comboBox.getToolkit().beep(); // when available use: UIManager.getLookAndFeel().provideErrorFeedback(comboBox);
}
setText(item.toString());
// select the completed part
highlightCompletedText(offs+str.length());
}
private void setText(String text) {
try {
// remove all text and insert the completed string
super.remove(0, getLength());
super.insertString(0, text, null);
} catch (BadLocationException e) {
throw new RuntimeException(e.toString());
}
}
private void highlightCompletedText(int start) {
editor.setCaretPosition(getLength());
editor.moveCaretPosition(start);
}
private void setSelectedItem(Object item) {
selecting = true;
model.setSelectedItem(item);
selecting = false;
}
private Object lookupItem(String pattern) {
Object selectedItem = model.getSelectedItem();
// only search for a different item if the currently selected does not match
if (selectedItem != null && startsWithIgnoreCase(selectedItem.toString(), pattern)) {
return selectedItem;
} else {
// iterate over all items
for (int i=0, n=model.getSize(); i < n; i++) {
Object currentItem = model.getElementAt(i);
// current item starts with the pattern?
if (currentItem != null && startsWithIgnoreCase(currentItem.toString(), pattern)) {
return currentItem;
}
}
}
// no item starts with the pattern => return null
return null;
}
// checks if str1 starts with str2 - ignores case
private boolean startsWithIgnoreCase(String str1, String str2) {
return str1.toUpperCase().startsWith(str2.toUpperCase());
}
private static void createAndShowGUI() {
// the combo box (add/modify items if you like to)
final JComboBox comboBox = new JComboBox(new Object[] {"Ester", "Jordi", "Jordina", "Jorge", "Sergi"});
enable(comboBox);
// create and show a window containing the combo box
final JFrame frame = new JFrame();
frame.setDefaultCloseOperation(3);
frame.getContentPane().add(comboBox);
frame.pack(); frame.setVisible(true);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
当我键入项目的第一个字母时，自动选择工作正常。但是，当我尝试从项目的中间键入内容时，即如果我键入“ ter” ，它将自动选择“ Ester” 。
请让我知道解决方法。
答案 0 :(得分：0)
我认为您要查找的是键入的单词和列表中的单词之间的'Levenshtein distance'。 Levenshtein距离最小的单词是最可能的匹配项（尽管请注意，可能有多个紧密匹配项，因此您需要弄清楚如何处理这些匹配项）。
我将从拥有两个列表而不是只有一个列表开始：显示列表和匹配列表。匹配的列表将全部小写，以使搜索更加容易。从那里开始，尝试学习以下课程来比较两个单词：https://commons.apache.org/proper/commons-text/jacoco/org.apache.commons.text.similarity/LevenshteinDistance.java.html