в 17:43, 31 мая 2010

2010-05-31T17:43:48Z

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2010-05-31T14:23:48Z

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== implements ItemSelectable ==



<source lang="java">

import java.awt.ItemSelectable;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.event.EventListenerList;
public class Main {
public static void main(String[] argv) throws Exception {
MyComponent component = new MyComponent();
JFrame f = new JFrame();
f.add(component);
f.setSize(300, 300);
f.setVisible(true);
}
}
class MyComponent extends JTextField implements ItemSelectable {
protected EventListenerList listenerList = new EventListenerList();
public Object[] getSelectedObjects() {
return new String[] { "a", "b", "c" };
}
public void addItemListener(ItemListener l) {
listenerList.add(ItemListener.class, l);
}
public void removeItemListener(ItemListener l) {
listenerList.remove(ItemListener.class, l);
}
void fireItemEvent(Object item, boolean sel) {
ItemEvent evt = new ItemEvent(this, ItemEvent.ITEM_STATE_CHANGED, item,
sel ? ItemEvent.SELECTED : ItemEvent.DESELECTED);
Object[] listeners = listenerList.getListenerList();
for (int i = 0; i < listeners.length - 2; i += 2) {
if (listeners[i] == ItemListener.class) {
((ItemListener) listeners[i + 1]).itemStateChanged(evt);
}
}
}
}

</source>



== ItemSelectable: getSelectedObjects() ==



<source lang="java">

import java.awt.BorderLayout;
import java.awt.ItemSelectable;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JComboBox;
import javax.swing.JFrame;
public class MainClass {
public static void main(final String args[]) {
final String labels[] = { "A", "B", "C", "D", "E" };
JFrame frame = new JFrame("Selecting JComboBox");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JComboBox comboBox = new JComboBox(labels);
frame.add(comboBox, BorderLayout.SOUTH);
ItemListener itemListener = new ItemListener() {
public void itemStateChanged(ItemEvent itemEvent) {
int state = itemEvent.getStateChange();
String stateString =
((state == ItemEvent.SELECTED) ? "Selected" : "Deselected");
System.out.println("Item: " + itemEvent.getItem());
System.out.println(", State: " + stateString);
ItemSelectable is = itemEvent.getItemSelectable();
System.out.println(", Selected: " + selectedString(is));
}
};
comboBox.addItemListener(itemListener);
frame.setSize(400, 200);
frame.setVisible(true);
}
static private String selectedString(ItemSelectable is) {
Object selected[] = is.getSelectedObjects();
return ((selected.length == 0) ? "null" : (String)selected[0]);
}
}

</source>

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в 17:43, 31 мая 2010

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