в 17:44, 31 мая 2010

2010-05-31T17:44:27Z

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2010-05-31T15:32:53Z

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== Add another selection - the third item ==



<source lang="java">
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
int start = 2;
int end = 2;
list.addSelectionInterval(start, end);
}
}</source>



== A single-selection JList. ==



<source lang="java">
import java.awt.FlowLayout;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JScrollPane;
import javax.swing.ListSelectionModel;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
public class Main {
String languages[] = { "Java", "Perl", "Python", "C++", "Basic", "C#" };
JList jlst = new JList(languages);
Main() {
JFrame jfrm = new JFrame("Use JList");
jfrm.setLayout(new FlowLayout());
jfrm.setSize(200, 160);
jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jlst.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
jlst.addListSelectionListener(new ListSelectionListener() {
public void valueChanged(ListSelectionEvent le) {
int idx = jlst.getSelectedIndex();
if (idx != -1)
System.out.println("Current selection: " + languages[idx]);
else
System.out.println("Please choose a language.");
}
});
jfrm.add(new JScrollPane(jlst));
jfrm.setSize(300, 300);
jfrm.setVisible(true);
}
public static void main(String args[]) {
new Main();
}
}</source>



== Clear all selections ==



<source lang="java">
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
list.clearSelection();
}
}</source>



== Deselect the first item ==



<source lang="java">
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
int start = 0;
int end = 0;
list.removeSelectionInterval(start, end);
}
}</source>



== Determine if there are any selected items ==



<source lang="java">
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
boolean anySelected = !list.isSelectionEmpty();
}
}</source>



== Get the index of the last selected item ==



<source lang="java">
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
int lastSelIx = list.getMaxSelectionIndex();
}
}</source>



== Getting the Selected Items in a JList Component ==



<source lang="java">
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
// Get the index of all the selected items
int[] selectedIx = list.getSelectedIndices();
// Get all the selected items using the indices
for (int i = 0; i < selectedIx.length; i++) {
Object sel = list.getModel().getElementAt(selectedIx[i]);
}
// Get the index of the first selected item
int firstSelIx = list.getSelectedIndex();
}
}</source>



== Listening for Changes to the Items in a JList Component ==



<source lang="java">
import javax.swing.DefaultListModel;
import javax.swing.JList;
import javax.swing.event.ListDataEvent;
import javax.swing.event.ListDataListener;
public class Main {
public static void main(String[] argv) throws Exception {
JList list = new JList();
// Register a list data listener
DefaultListModel model = (DefaultListModel) list.getModel();
model.addListDataListener(new MyListDataListener());
}
}
class MyListDataListener implements ListDataListener {
public void intervalAdded(ListDataEvent evt) {
DefaultListModel model = (DefaultListModel) evt.getSource();
int start = evt.getIndex0();
int end = evt.getIndex1();
int count = end - start + 1;
for (int i = start; i <= end; i++) {
Object item = model.getElementAt(i);
}
}
public void intervalRemoved(ListDataEvent evt) {
int start = evt.getIndex0();
int end = evt.getIndex1();
int count = end - start + 1;
}
public void contentsChanged(ListDataEvent evt) {
DefaultListModel model = (DefaultListModel) evt.getSource();
int start = evt.getIndex0();
int end = evt.getIndex1();
int count = end - start + 1;
for (int i = start; i <= end; i++) {
Object item = model.getElementAt(i);
}
}
}</source>



== Listening for Changes to the Selection in a JList Component ==



<source lang="java">
import javax.swing.JList;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
list.addListSelectionListener(new MyListSelectionListener());
}
}
class MyListSelectionListener implements ListSelectionListener {
public void valueChanged(ListSelectionEvent evt) {
if (!evt.getValueIsAdjusting()) {
JList list = (JList) evt.getSource();
Object[] selected = list.getSelectedValues();
for (int i = 0; i < selected.length; i++) {
Object sel = selected[i];
}
}
}
}</source>



== List selection event ==



<source lang="java">
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Vector;
import javax.swing.JComboBox;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.ListModel;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
public class SelectionHandler implements ActionListener, ListSelectionListener {
private JLabel direction;
private JList source, destination;
public SelectionHandler(JLabel d, JList left, JList right) {
direction = d;
source = left;
destination = right;
}
public void actionPerformed(ActionEvent a) {
JComboBox cb = (JComboBox) a.getSource();
String selected = (String) cb.getSelectedItem();
String current = direction.getText();
if (!selected.equals(current)) {
direction.setText(selected);
JList temp = source;
source = destination;
destination = temp;
source.clearSelection();
destination.clearSelection();
}
}
public void valueChanged(ListSelectionEvent e) {
JList list = (JList) e.getSource();
String item = (String) source.getSelectedValue();
System.out.println(item);
if (item != null && !item.equals("")) {
removeFromSource(item);
addToDestination(item);
}
}
private void removeFromSource(String item) {
ListModel model = source.getModel();
Vector listData = new Vector();
for (int i = 0; i < model.getSize(); i++) {
listData.addElement(model.getElementAt(i));
}
listData.removeElement(item);
source.setListData(listData);
}
private void addToDestination(String item) {
ListModel model = destination.getModel();
Vector listData = new Vector();
for (int i = 0; i < model.getSize(); i++) {
listData.addElement(model.getElementAt(i));
}
listData.addElement(item);
destination.setListData(listData);
}
}</source>



== Multiple ranges of selected items are allowed ==



<source lang="java">
import javax.swing.DefaultListSelectionModel;
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
list.setSelectionMode(DefaultListSelectionModel.MULTIPLE_INTERVAL_SELECTION);
}
}</source>



== Select all the items ==



<source lang="java">
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
int start = 0;
int end = list.getModel().getSize() - 1;
if (end >= 0) {
list.setSelectionInterval(start, end);
}
}
}</source>



== Select the first item ==



<source lang="java">
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
int start = 0;
int end = 0;
list.setSelectionInterval(start, end);
}
}</source>



== Setting the Selected Items in a JList Component ==



<source lang="java">
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
// Select the second item
int start = 1;
int end = 1;
list.setSelectionInterval(start, end);
}
}</source>



== Setting the Selection Mode of a JList Component ==



<source lang="java">
import javax.swing.DefaultListSelectionModel;
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
// Get the current selection model mode
int mode = list.getSelectionMode(); // MULTIPLE_INTERVAL_SELECTION
// Only one item can be selected
list.setSelectionMode(DefaultListSelectionModel.SINGLE_SELECTION);
}
}</source>



== The selected items must be in a contiguous range ==



<source lang="java">
import javax.swing.DefaultListSelectionModel;
import javax.swing.JList;
public class Main {
public static void main(String[] argv) throws Exception {
String[] items = { "A", "B", "C", "D" };
JList list = new JList(items);
list.setSelectionMode(DefaultListSelectionModel.SINGLE_INTERVAL_SELECTION);
}
}</source>

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Admin: 1 версия