Handling List  in java

In this example we are going to handle List.
To handle the List we are using three type of package. One is java.awt.* second is  java.applet.* and third is java.awt.event.*; .The java.awt.* is used for GUI interface. AWT classes are contain in this package. The  java.applet.* package is used to create an applet and java.awt.event.*; defined within the java.awt.*; package is a subclass of EventObject. It is a super class of all AWT-based event.The list provides a compact ,multiple choice and scrolling selection list.

List provide these contractures:
List(): this allowed to select only one item at any one time. 
List(int numRows): the num Rows specifies the number of entries in the list that will always visible .
List(int numRows, boolean multiple Select): if multiple Select is true then we will select two or more item at a time.
To add a selection to the list, call add().
void add(string name); add item to the end of list.
void add(string name,int index); add item to the index.
In our example first we implement two interface:
ActionListener();  each listener implement the ActionLinstner.
actionPerformed(); When a option is selected or an event is occur this interface is called.
To deterrmine which item is currently selected, you may call :
String getSelectedItem(); It returns a string containing the name of the item.
or  int getSelectedIndex(); It return the index of the item.
To obtain the number of item in the list call:
 int getItemCount();
In our example we create two List one is  country and other is city.

// Handling List 
import java.awt.*;
import java.awt.event.*;
import java.applet.*;
/*
<applet code="ListDemo" width=300 height=200>
</applet>
*/
public class ListDemo extends Applet implements ActionListener{
List country,city;
String msg="";
public void init(){
 country = new List(3,false);
 city = new List(3,false);
country.add("India");
country.add("Rusia");
country.add("Pakistan");
country.add("Srilanka");
city.add("unnao");
city.add("Lucknow");
city.add("Lahour"); 
city.add("Kuvait");
add(country);
add(city);
country.addActionListener(this);
city.addActionListener(this);
}
public void actionPerformed(ActionEvent ae){
repaint();
}
public void paint(Graphics g){
int idx[];
msg="your country name is:";
idx=country.getSelectedIndexes();
for(int i=0;i<idx.length;i++)
msg +=country.getItem(idx[i]) +" ";
g.drawString(msg,6,120);
msg="your city name is:";
msg +=city.getSelectedItem();
g.drawString(msg,6,140);
}
}

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Output Of Example