Bem Pessoal to construindo um sistema em java. Eu gostaria de saber como faco para fazer uma pesquisa num test field. Ele deve funcionar do seguinte jeito.
Logo que o usuario comeca a digitar ele ja ta procurando sem ter de ter um botao pesquisar propriamente dito.
Use o evento key pressed no text field.
[quote=psp-player]Bem Pessoal to construindo um sistema em java. Eu gostaria de saber como faco para fazer uma pesquisa num test field. Ele deve funcionar do seguinte jeito.
Logo que o usuario comeca a digitar ele ja ta procurando sem ter de ter um botao pesquisar propriamente dito. [/quote]
Isso não é trivial de fazer. Procure pelo AutoCompleteDecorator do pacote Swingx.
Geralmente não fazemos esse tipo de tratamento pelo evento, como o chimufox indicou também.
O ideal é tratar pelo Document, como o Decorator que indiquei faz.
Para o Autocomplete com o JComboBox utilizo essa classe:
[code]import java.awt.event.*;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.text.Collator;
import java.util.Locale;
import javax.swing.;
import javax.swing.text.;
public class AutoComplete extends PlainDocument {
private static final long serialVersionUID = 5157735565710292356L;
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 AutoComplete(final JComboBox comboBox) {
this.comboBox = comboBox;
model = comboBox.getModel();
comboBox.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if (!selecting) highlightCompletedText(0);
}
});
comboBox.addPropertyChangeListener(new PropertyChangeListener() {
@Override
public void propertyChange(PropertyChangeEvent e) {
if (e.getPropertyName().equals("editor")) configureEditor((ComboBoxEditor) e.getNewValue());
if (e.getPropertyName().equals("model")) model = (ComboBoxModel) e.getNewValue();
}
});
editorKeyListener = new KeyAdapter() {
@Override
public void keyPressed(KeyEvent e) {
if (comboBox.isDisplayable()) comboBox.setPopupVisible(true);
hitBackspace=false;
// switch (e.getKeyCode()) {
// // determine if the pressed key is backspace (needed by the remove method)
// case KeyEvent.VK_BACK_SPACE : hitBackspace=true;
// hitBackspaceOnSelection=editor.getSelectionStart()!=editor.getSelectionEnd();
// break;
// // ignore delete key
//// case KeyEvent.VK_DELETE : e.consume();
//// comboBox.getToolkit().beep();
//// break;
// }
}
};
// 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
editorFocusListener = new FocusAdapter() {
@Override
public void focusGained(FocusEvent e) {
highlightCompletedText(0);
}
@Override
public void focusLost(FocusEvent e) {
// Workaround for Bug 5100422 - Hide Popup on focus loss
if (hidePopupOnFocusLoss) comboBox.setPopupVisible(false);
}
};
configureEditor(comboBox.getEditor());
// 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 AutoComplete(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);
}
}
@Override
public void remove(int offs, int len) throws BadLocationException {
// return immediately when selecting an item
if (selecting) return;
if (hitBackspace) {
// user hit backspace => move the selection backwards
// old item keeps being selected
if (offs>0) {
if (hitBackspaceOnSelection) offs--;
} else {
// User hit backspace with the cursor positioned on the start => beep
comboBox.getToolkit().beep(); // when available use: UIManager.getLookAndFeel().provideErrorFeedback(comboBox);
}
highlightCompletedText(offs);
} else {
super.remove(offs, len);
}
}
@Override
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);
}
if(item != null)
setText(item.toString());
else
setText("");
// 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 && startsWithIgnoreAccentsAndCase(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 && startsWithIgnoreAccentsAndCase(currentItem.toString(), pattern)) {
return currentItem;
}
}
}
// no item starts with the pattern => return null
return null;
}
private static Collator collator = null;
private static Collator getCollator() {
if (collator == null) {
collator = Collator.getInstance (new Locale ("pt", "BR"));
collator.setStrength(Collator.PRIMARY);
}
return collator;
}
public static boolean startsWithIgnoreAccentsAndCase(String source,String target) {
if (target.length() > source.length())
return false;
return getCollator().compare(source.substring(0, target.length()),target) == 0;
}
} [/code]
Como usar? Fácil!
Talvez sirva com o JTextField 
ups nao existe um link especifico que da para eu estudar esse problema.