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JAVA Scrollbar, MenuItem and Menu, PopupMenu

ava AWT Scrollbar

The object of Scrollbar class is used to add horizontal and vertical scrollbar. Scrollbar is a GUI component allows us to see invisible number of rows and columns.

AWT Scrollbar class declaration

  1. public class Scrollbar extends Component implements Adjustable, Accessible  

Java AWT Scrollbar Example

  1. import java.awt.*;  
  2. class ScrollbarExample{  
  3. ScrollbarExample(){  
  4.             Frame f= new Frame("Scrollbar Example");  
  5.             Scrollbar s=new Scrollbar();  
  6.             s.setBounds(100,100, 50,100);  
  7.             f.add(s);  
  8.             f.setSize(400,400);  
  9.             f.setLayout(null);  
  10.             f.setVisible(true);  
  11. }  
  12. public static void main(String args[]){  
  13.        new ScrollbarExample();  
  14. }  
  15. }  

Output:

java awt scrollbar example 1

Java AWT Scrollbar Example with AdjustmentListener

  1. import java.awt.*;  
  2. import java.awt.event.*;  
  3. class ScrollbarExample{  
  4.      ScrollbarExample(){  
  5.             Frame f= new Frame("Scrollbar Example");  
  6.             final Label label = new Label();          
  7.             label.setAlignment(Label.CENTER);  
  8.             label.setSize(400,100);  
  9.             final Scrollbar s=new Scrollbar();  
  10.             s.setBounds(100,100, 50,100);  
  11.             f.add(s);f.add(label);   
  12.             f.setSize(400,400);  
  13.             f.setLayout(null);  
  14.             f.setVisible(true);  
  15.             s.addAdjustmentListener(new AdjustmentListener() {  
  16.                 public void adjustmentValueChanged(AdjustmentEvent e) {  
  17.                    label.setText("Vertical Scrollbar value is:"+ s.getValue());  
  18.                 }  
  19.             });  
  20.          }  
  21. public static void main(String args[]){  
  22. new ScrollbarExample();  
  23. }  
  24. }  

Output:

java awt scrollbar example 2

Java AWT MenuItem and Menu

The object of MenuItem class adds a simple labeled menu item on menu. The items used in a menu must belong to the MenuItem or any of its subclass.

The object of Menu class is a pull down menu component which is displayed on the menu bar. It inherits the MenuItem class.

AWT MenuItem class declaration

  1. public class MenuItem extends MenuComponent implements Accessible  

AWT Menu class declaration

  1. public class Menu extends MenuItem implements MenuContainer, Accessible  

Java AWT MenuItem and Menu Example

  1. import java.awt.*;  
  2. class MenuExample  
  3. {  
  4.      MenuExample(){  
  5.          Frame f= new Frame("Menu and MenuItem Example");  
  6.          MenuBar mb=new MenuBar();  
  7.          Menu menu=new Menu("Menu");  
  8.          Menu submenu=new Menu("Sub Menu");  
  9.          MenuItem i1=new MenuItem("Item 1");  
  10.          MenuItem i2=new MenuItem("Item 2");  
  11.          MenuItem i3=new MenuItem("Item 3");  
  12.          MenuItem i4=new MenuItem("Item 4");  
  13.          MenuItem i5=new MenuItem("Item 5");  
  14.          menu.add(i1);  
  15.          menu.add(i2);  
  16.          menu.add(i3);  
  17.          submenu.add(i4);  
  18.          submenu.add(i5);  
  19.          menu.add(submenu);  
  20.          mb.add(menu);  
  21.          f.setMenuBar(mb);  
  22.          f.setSize(400,400);  
  23.          f.setLayout(null);  
  24.          f.setVisible(true);  
  25. }  
  26. public static void main(String args[])  
  27. {  
  28. new MenuExample();  
  29. }  
  30. }  

Output:

java awt menuitem and menu example 1

ava AWT PopupMenu

PopupMenu can be dynamically popped up at specific position within a component. It inherits the Menu class.

AWT PopupMenu class declaration

  1. public class PopupMenu extends Menu implements MenuContainer, Accessible  

Java AWT PopupMenu Example

  1. import java.awt.*;  
  2. import java.awt.event.*;  
  3. class PopupMenuExample  
  4. {  
  5.      PopupMenuExample(){  
  6.          final Frame f= new Frame("PopupMenu Example");  
  7.          final PopupMenu popupmenu = new PopupMenu("Edit");   
  8.          MenuItem cut = new MenuItem("Cut");  
  9.          cut.setActionCommand("Cut");  
  10.          MenuItem copy = new MenuItem("Copy");  
  11.          copy.setActionCommand("Copy");  
  12.          MenuItem paste = new MenuItem("Paste");  
  13.          paste.setActionCommand("Paste");      
  14.          popupmenu.add(cut);  
  15.          popupmenu.add(copy);  
  16.          popupmenu.add(paste);        
  17.          f.addMouseListener(new MouseAdapter() {  
  18.             public void mouseClicked(MouseEvent e) {              
  19.                 popupmenu.show(f , e.getX(), e.getY());  
  20.             }                 
  21.          });  
  22.          f.add(popupmenu);   
  23.          f.setSize(400,400);  
  24.          f.setLayout(null);  
  25.          f.setVisible(true);  
  26.      }  
  27. public static void main(String args[])  
  28. {  
  29.         new PopupMenuExample();  
  30. }  
  31. }  

Output:

java awt popup example 1 java awt popup example 2
Anurag Rana Educator CSE/IT

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