Java AWT | Choice Class

Choice class is part of Java Abstract Window Toolkit(AWT). The Choice class presents a pop- up menu for the user, the user may select an item from the popup menu. The selected item appears on the top. The Choice class inherits the Component.

Constructor for the Choice class

• Choice() : creates an new empty choice menu .

Different Methods for the Choice Class

Method	Explanation
add(String s)	adds an item to this Choice menu.
addItemListener(ItemListener l)	adds the specified item listener to receive item events from this Choice menu.
addNotify()	creates the Choice’s peer.
getAccessibleContext()	gets the AccessibleContext associated with this Choice.
getItem(int i)	gets the string at the specified index in this Choice menu
getItemCount()	returns the number of items in this Choice menu.
getItemListeners()	returns an array of all the item listeners registered on this choice.
getListeners(Class l)	returns an array of all the objects currently registered as FooListeners upon this Choice.
getSelectedIndex()	returns the index of the currently selected item.
getSelectedItem()	gets a representation of the current choice as a string.
insert(String s, int i)	inserts the item into this choice at the specified position.
paramString()	returns a string representing the state of this Choice menu.
processEvent(AWTEvent e)	processes events on this choice.
processItemEvent(ItemEvent e)	processes item events occurring on this Choice menu by dispatching them to any registered ItemListener objects.
remove(int p)	removes an item from the choice menu at the specified position.
remove(String s)	removes the first occurrence of item from the Choice menu.
removeAll()	removes all items from the choice menu.
select(int p)	sets the selected item in this Choice menu to be the item at the specified position.

Below programs illustrate the Choice class in Java AWT:

• Program to create a simple choice and add elements to it:

  // Java Program to create a simple
  // choice and add elements to it .
  import java.awt.*;
  import javax.swing.*;
  
  class choice {
  
      // choice
      static Choice c;
  
      // frame
      static JFrame f;
  
      // default constructor
      choice()
      {
      }
  
      // Main Method
      public static void main(String args[])
      {
  
          // create a frame
          f = new JFrame("choice");
  
          // create e panel
          JPanel p = new JPanel();
  
          // create a choice
          c = new Choice();
  
          // add element to the list
          c.add("Andrew");
          c.add("Arnab");
          c.add("Ankit");
  
          // add choice to panel
          p.add(c);
  
          // add panel to the frame
          f.add(p);
  
          // show the frame
          f.show();
          f.setSize(300, 300);
      }
  }

  Output :
  

• Program to create a simple choice and add ItemListener to it:

  // Java  Program to create a simple
  // choice and add ItemListener to it
  import java.awt.*;
  import javax.swing.*;
  import java.awt.event.*;
  
  class choice implements ItemListener {
  
      // choice
      static Choice c;
  
      // frame
      static JFrame f;
  
      // label
      static Label l;
  
      // default constructor
      choice()
      {
      }
  
      // Main Method
      public static void main(String args[])
      {
  
          // create a frame
          f = new JFrame("choice");
  
          // object
          choice ch = new choice();
  
          // create e panel
          JPanel p = new JPanel();
  
          // create a choice
          c = new Choice();
  
          // add element to the list
          c.add("Andrew");
          c.add("Arnab");
          c.add("Ankit");
  
          // add itemListener to it
          c.addItemListener(ch);
  
          // create a label
          l = new Label();
  
          // set the label text
          l.setText(c.getSelectedItem() + " selected");
  
          // add choice to panel
          p.add(c);
          p.add(l);
  
          // add panel to the frame
          f.add(p);
  
          // show the frame
          f.show();
          f.setSize(300, 300);
      }
  
      // if an item is selected
      public void itemStateChanged(ItemEvent e)
      {
          l.setText(c.getSelectedItem() + " selected");
      }
  }

  Output :

  

• Program to create a choice and manually add elements to it (using add(String s) function):

  // Java Program to create a choice and
  // manually add elements to it
  // (using add(String s) function)
  import java.awt.*;
  import javax.swing.*;
  import java.awt.event.*;
  
  class choice implements ItemListener, ActionListener {
  
      // choice
      static Choice c;
  
      // frame
      static JFrame f;
  
      // label
      static Label l;
  
      // textfield
      static TextField tf;
  
      // default constructor
      choice()
      {
      }
  
      // Main Method
      public static void main(String args[])
      {
  
          // create a frame
          f = new JFrame("choice");
  
          // object
          choice ch = new choice();
  
          // create e panel
          JPanel p = new JPanel();
  
          // create a choice
          c = new Choice();
  
          // add element to the list
          c.add("Andrew");
  
          // create a textfield
          tf = new TextField(7);
  
          // create a button
          Button b = new Button("ok");
  
          // add actionListener
          b.addActionListener(ch);
  
          // add itemListener to it
          c.addItemListener(ch);
  
          // create a label
          l = new Label();
          Label l1 = new Label("add names");
  
          // set the label text
          l.setText(c.getSelectedItem() + " selected");
  
          // add choice to panel
          p.add(c);
          p.add(l);
          p.add(l1);
          p.add(tf);
          p.add(b);
  
          // add panel to the frame
          f.add(p);
  
          // show the frame
          f.show();
          f.setSize(250, 300);
      }
  
      // if an item is selected
      public void itemStateChanged(ItemEvent e)
      {
          l.setText(c.getSelectedItem() + " selected");
      }
  
      // if button is pressed
      public void actionPerformed(ActionEvent e)
      {
          // add item to the choice
          c.add(tf.getText());
      }
  }

  Output :

  

Note: The programs might not run in an online IDE please use an offline IDE.

Reference : https://docs.oracle.com/javase/7/docs/api/java/awt/Choice.html