用下拉列表在Java中创建文本框自动填入 [英] Create a autocompleting textbox in Java with a dropdown list
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问题描述
我想创建一个自动提示文本框这将每个按键释放事件查询数据库。
这一部分很容易，但我想给不错的视觉它。一些类似于我们在网站上看到像在Facebook中搜索自动提示文本框。
I want to create a auto-suggest text box which would query the database at each key release event. That part is easy, but I want to give nice visual to it. Something similar to the auto-suggest text box we see in websites like searching in Facebook.
如何使这样的接口？
一个天真的想法是有一个JList，只是放在下面的文本框中，并设置它在它的结果可见找到一个。
A naive idea would be to have a JList placed just below the text box and set it visible with the results in it on finding one.
任何更好的想法或做它的标准方式？
Any better idea or a standard way of doing it?
推荐答案
@ syb0rg的答案是比较容易的，因为它使用一个第三方库。
@syb0rg's answer is easier, as it uses an 3rd party library.
不过我用了另一种方式：
However I used an alternate approach:
它使用 AutoSuggestor 调用自定义类，它接受一个的JTextField ，其窗口的的ArrayList＆LT;弦乐＆GT; 。通过传递的JTextField 引用的DocumentListener 添加这将做检查是什么字输入以及是否显示建议工作或者没有，如果有啥显示的建议。当一个单词键入的DocumentListener 将火 wordTyped（字符串wordTyped）方法与目前的字正在键入或（在至少多少字有史以来已输入），在 wordTyped（..）字将针对那些被检查 AutoSuggestor 取值类字典的是字符串这可能是一个基本的的ArrayList 在飞行设置在下面的例子所示：
It uses a custom class called AutoSuggestor which accepts a JTextField, its Window an ArrayList<String> of words to check typed words against, a background color and text color, and suggestion focus colour as well as an opacity value. By passing JTextField reference a DocumentListener is added which will do the work of checking what word is typed and whether to display suggestions or not and if so what suggestions to display. When a word is typed the DocumentListener will firewordTyped(String wordTyped) method with the current word being typed or (at least how much ever of the word has been typed), in wordTyped(..) the word will be checked against those in the AutoSuggestors classes dictionary which is a basic ArrayList of String this can be set on the fly as seen in the below example:
（现在你将不得不使用鼠标点击你想自动完成，或用字<大骨节病>下的横向建议和的文本框和<大骨节病>输入使用遍历时选择建议的下的键，我还没有实施<大骨节病> UP 尚）：
(For now you will have to use mouse and click the word you want to be auto completed, or use DOWN to transverse suggestions and the textfield and ENTER to select suggestion when traversing using down key. I have not yet implemented UP yet):
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.ArrayList;
import javax.swing.AbstractAction;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.JWindow;
import javax.swing.KeyStroke;
import javax.swing.SwingUtilities;
import javax.swing.border.LineBorder;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
/**
* @author David
*/
public class Test {
public Test() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JTextField f = new JTextField(10);
AutoSuggestor autoSuggestor = new AutoSuggestor(f, frame, null, Color.WHITE.brighter(), Color.BLUE, Color.RED, 0.75f) {
@Override
boolean wordTyped(String typedWord) {
//create list for dictionary this in your case might be done via calling a method which queries db and returns results as arraylist
ArrayList<String> words = new ArrayList<>();
words.add("hello");
words.add("heritage");
words.add("happiness");
words.add("goodbye");
words.add("cruel");
words.add("car");
words.add("war");
words.add("will");
words.add("world");
words.add("wall");
setDictionary(words);
//addToDictionary("bye");//adds a single word
return super.wordTyped(typedWord);//now call super to check for any matches against newest dictionary
}
};
JPanel p = new JPanel();
p.add(f);
frame.add(p);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
new Test();
}
});
}
}
class AutoSuggestor {
private final JTextField textField;
private final Window container;
private JPanel suggestionsPanel;
private JWindow autoSuggestionPopUpWindow;
private String typedWord;
private final ArrayList<String> dictionary = new ArrayList<>();
private int currentIndexOfSpace, tW, tH;
private DocumentListener documentListener = new DocumentListener() {
@Override
public void insertUpdate(DocumentEvent de) {
checkForAndShowSuggestions();
}
@Override
public void removeUpdate(DocumentEvent de) {
checkForAndShowSuggestions();
}
@Override
public void changedUpdate(DocumentEvent de) {
checkForAndShowSuggestions();
}
};
private final Color suggestionsTextColor;
private final Color suggestionFocusedColor;
public AutoSuggestor(JTextField textField, Window mainWindow, ArrayList<String> words, Color popUpBackground, Color textColor, Color suggestionFocusedColor, float opacity) {
this.textField = textField;
this.suggestionsTextColor = textColor;
this.container = mainWindow;
this.suggestionFocusedColor = suggestionFocusedColor;
this.textField.getDocument().addDocumentListener(documentListener);
setDictionary(words);
typedWord = "";
currentIndexOfSpace = 0;
tW = 0;
tH = 0;
autoSuggestionPopUpWindow = new JWindow(mainWindow);
autoSuggestionPopUpWindow.setOpacity(opacity);
suggestionsPanel = new JPanel();
suggestionsPanel.setLayout(new GridLayout(0, 1));
suggestionsPanel.setBackground(popUpBackground);
addKeyBindingToRequestFocusInPopUpWindow();
}
private void addKeyBindingToRequestFocusInPopUpWindow() {
textField.getInputMap(JComponent.WHEN_FOCUSED).put(KeyStroke.getKeyStroke(KeyEvent.VK_DOWN, 0, true), "Down released");
textField.getActionMap().put("Down released", new AbstractAction() {
@Override
public void actionPerformed(ActionEvent ae) {//focuses the first label on popwindow
for (int i = 0; i < suggestionsPanel.getComponentCount(); i++) {
if (suggestionsPanel.getComponent(i) instanceof SuggestionLabel) {
((SuggestionLabel) suggestionsPanel.getComponent(i)).setFocused(true);
autoSuggestionPopUpWindow.toFront();
autoSuggestionPopUpWindow.requestFocusInWindow();
suggestionsPanel.requestFocusInWindow();
suggestionsPanel.getComponent(i).requestFocusInWindow();
break;
}
}
}
});
suggestionsPanel.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT).put(KeyStroke.getKeyStroke(KeyEvent.VK_DOWN, 0, true), "Down released");
suggestionsPanel.getActionMap().put("Down released", new AbstractAction() {
int lastFocusableIndex = 0;
@Override
public void actionPerformed(ActionEvent ae) {//allows scrolling of labels in pop window (I know very hacky for now :))
ArrayList<SuggestionLabel> sls = getAddedSuggestionLabels();
int max = sls.size();
if (max > 1) {//more than 1 suggestion
for (int i = 0; i < max; i++) {
SuggestionLabel sl = sls.get(i);
if (sl.isFocused()) {
if (lastFocusableIndex == max - 1) {
lastFocusableIndex = 0;
sl.setFocused(false);
autoSuggestionPopUpWindow.setVisible(false);
setFocusToTextField();
checkForAndShowSuggestions();//fire method as if document listener change occured and fired it
} else {
sl.setFocused(false);
lastFocusableIndex = i;
}
} else if (lastFocusableIndex <= i) {
if (i < max) {
sl.setFocused(true);
autoSuggestionPopUpWindow.toFront();
autoSuggestionPopUpWindow.requestFocusInWindow();
suggestionsPanel.requestFocusInWindow();
suggestionsPanel.getComponent(i).requestFocusInWindow();
lastFocusableIndex = i;
break;
}
}
}
} else {//only a single suggestion was given
autoSuggestionPopUpWindow.setVisible(false);
setFocusToTextField();
checkForAndShowSuggestions();//fire method as if document listener change occured and fired it
}
}
});
}
private void setFocusToTextField() {
container.toFront();
container.requestFocusInWindow();
textField.requestFocusInWindow();
}
public ArrayList<SuggestionLabel> getAddedSuggestionLabels() {
ArrayList<SuggestionLabel> sls = new ArrayList<>();
for (int i = 0; i < suggestionsPanel.getComponentCount(); i++) {
if (suggestionsPanel.getComponent(i) instanceof SuggestionLabel) {
SuggestionLabel sl = (SuggestionLabel) suggestionsPanel.getComponent(i);
sls.add(sl);
}
}
return sls;
}
private void checkForAndShowSuggestions() {
typedWord = getCurrentlyTypedWord();
suggestionsPanel.removeAll();//remove previos words/jlabels that were added
//used to calcualte size of JWindow as new Jlabels are added
tW = 0;
tH = 0;
boolean added = wordTyped(typedWord);
if (!added) {
if (autoSuggestionPopUpWindow.isVisible()) {
autoSuggestionPopUpWindow.setVisible(false);
}
} else {
showPopUpWindow();
setFocusToTextField();
}
}
protected void addWordToSuggestions(String word) {
SuggestionLabel suggestionLabel = new SuggestionLabel(word, suggestionFocusedColor, suggestionsTextColor, this);
calculatePopUpWindowSize(suggestionLabel);
suggestionsPanel.add(suggestionLabel);
}
public String getCurrentlyTypedWord() {//get newest word after last white spaceif any or the first word if no white spaces
String text = textField.getText();
String wordBeingTyped = "";
if (text.contains(" ")) {
int tmp = text.lastIndexOf(" ");
if (tmp >= currentIndexOfSpace) {
currentIndexOfSpace = tmp;
wordBeingTyped = text.substring(text.lastIndexOf(" "));
}
} else {
wordBeingTyped = text;
}
return wordBeingTyped.trim();
}
private void calculatePopUpWindowSize(JLabel label) {
//so we can size the JWindow correctly
if (tW < label.getPreferredSize().width) {
tW = label.getPreferredSize().width;
}
tH += label.getPreferredSize().height;
}
private void showPopUpWindow() {
autoSuggestionPopUpWindow.getContentPane().add(suggestionsPanel);
autoSuggestionPopUpWindow.setMinimumSize(new Dimension(textField.getWidth(), 30));
autoSuggestionPopUpWindow.setSize(tW, tH);
autoSuggestionPopUpWindow.setVisible(true);
int windowX = 0;
int windowY = 0;
windowX = container.getX() + textField.getX() + 5;
if (suggestionsPanel.getHeight() > autoSuggestionPopUpWindow.getMinimumSize().height) {
windowY = container.getY() + textField.getY() + textField.getHeight() + autoSuggestionPopUpWindow.getMinimumSize().height;
} else {
windowY = container.getY() + textField.getY() + textField.getHeight() + autoSuggestionPopUpWindow.getHeight();
}
autoSuggestionPopUpWindow.setLocation(windowX, windowY);
autoSuggestionPopUpWindow.setMinimumSize(new Dimension(textField.getWidth(), 30));
autoSuggestionPopUpWindow.revalidate();
autoSuggestionPopUpWindow.repaint();
}
public void setDictionary(ArrayList<String> words) {
dictionary.clear();
if (words == null) {
return;//so we can call constructor with null value for dictionary without exception thrown
}
for (String word : words) {
dictionary.add(word);
}
}
public JWindow getAutoSuggestionPopUpWindow() {
return autoSuggestionPopUpWindow;
}
public Window getContainer() {
return container;
}
public JTextField getTextField() {
return textField;
}
public void addToDictionary(String word) {
dictionary.add(word);
}
boolean wordTyped(String typedWord) {
if (typedWord.isEmpty()) {
return false;
}
//System.out.println("Typed word: " + typedWord);
boolean suggestionAdded = false;
for (String word : dictionary) {//get words in the dictionary which we added
boolean fullymatches = true;
for (int i = 0; i < typedWord.length(); i++) {//each string in the word
if (!typedWord.toLowerCase().startsWith(String.valueOf(word.toLowerCase().charAt(i)), i)) {//check for match
fullymatches = false;
break;
}
}
if (fullymatches) {
addWordToSuggestions(word);
suggestionAdded = true;
}
}
return suggestionAdded;
}
}
class SuggestionLabel extends JLabel {
private boolean focused = false;
private final JWindow autoSuggestionsPopUpWindow;
private final JTextField textField;
private final AutoSuggestor autoSuggestor;
private Color suggestionsTextColor, suggestionBorderColor;
public SuggestionLabel(String string, final Color borderColor, Color suggestionsTextColor, AutoSuggestor autoSuggestor) {
super(string);
this.suggestionsTextColor = suggestionsTextColor;
this.autoSuggestor = autoSuggestor;
this.textField = autoSuggestor.getTextField();
this.suggestionBorderColor = borderColor;
this.autoSuggestionsPopUpWindow = autoSuggestor.getAutoSuggestionPopUpWindow();
initComponent();
}
private void initComponent() {
setFocusable(true);
setForeground(suggestionsTextColor);
addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent me) {
super.mouseClicked(me);
replaceWithSuggestedText();
autoSuggestionsPopUpWindow.setVisible(false);
}
});
getInputMap(JComponent.WHEN_FOCUSED).put(KeyStroke.getKeyStroke(KeyEvent.VK_ENTER, 0, true), "Enter released");
getActionMap().put("Enter released", new AbstractAction() {
@Override
public void actionPerformed(ActionEvent ae) {
replaceWithSuggestedText();
autoSuggestionsPopUpWindow.setVisible(false);
}
});
}
public void setFocused(boolean focused) {
if (focused) {
setBorder(new LineBorder(suggestionBorderColor));
} else {
setBorder(null);
}
repaint();
this.focused = focused;
}
public boolean isFocused() {
return focused;
}
private void replaceWithSuggestedText() {
String suggestedWord = getText();
String text = textField.getText();
String typedWord = autoSuggestor.getCurrentlyTypedWord();
String t = text.substring(0, text.lastIndexOf(typedWord));
String tmp = t + text.substring(text.lastIndexOf(typedWord)).replace(typedWord, suggestedWord);
textField.setText(tmp + " ");
}
}
因为它的立场，唯一可能需要的补充IMO为：
As it stands the only possible needed additions IMO is:
- <大骨节病> UP 重点用于弹出自动建议盒子内的物品traversablity，所以我们可以去一个向上的方向。
- UP key Focus traversablity for items within the popup autosuggestions box so we can go in a upward direction.
如果有任何扭结还是让我知道我会看看我能做些什么。但似乎是运行良好（触摸木头）。
If there are any kinks lemme know I'll see what I can do. But Seems to be running fine (touch wood).
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