How To Create Menu Bar IN AWT

Introduction:

In today's article you will learn what a Menu is and how to create a Menu Bar using AWT.

Menu:

Menus are very familiar to a programmers in the Windows environment. A menu has a pull-down list of menu items from which the user can select one at a time. When many options in multiple categories exist for selection by the user, menus are the best choice since they take less space on the frame. A click on the MenuItem generates an ActionEvent and is handled by an ActionListener. A Menu and a MenuItem are not components siince they are not subclasses of the java.awt.Component class. They are derived from the MenuComponent class. The following hierarchy illustrates that.

Menu Hierarchy:

Menu creation involves many classes, like MenuBar, MenuItem and Menu and one is added to the other.

MenuComponent

A MenuComponent is the highst level class of all menu classes; like a Component it is the super most class for all component classes like Button, Frame etc. A MenuBar is capable of holding the menus and a Menu can hold menu items. Menus are placed on a menu bar.

Procedure for Creating Menus

The following is the procedure for creating menus:

• Create menu bar
• Add menu bar to the frame
• Create menus
• Add menus to menu bar
• Create menu items
• Add menu items to menus
• Event handling

In the following program, a menu is created and populated with menu items. User's selected menu item or sub-menu item's

1. import java.awt.*;
2. class AWTMenu extends Frame
3. {
4. MenuBar mbar;
5. Menu menu,submenu;
6. MenuItem m1,m2,m3,m4,m5;
7. public AWTMenu()
8. {
9. // Set frame properties
10. setTitle("AWT Menu"); // Set the title
11. setSize(300,300); // Set size to the frame
12. setLayout(new FlowLayout()); // Set the layout
13. setVisible(true); // Make the frame visible
14. setLocationRelativeTo(null); // Center the frame
15. // Create the menu bar
16. mbar=new MenuBar();
17. // Create the menu
18. menu=new Menu("Menu");
19. // Create the submenu
20. submenu=new Menu("Sub Menu");
21. // Create MenuItems
22. m1=new MenuItem("Menu Item 1");
23. m2=new MenuItem("Menu Item 2");
24. m3=new MenuItem("Menu Item 3");
25. m4=new MenuItem("Menu Item 4");
26. m5=new MenuItem("Menu Item 5");
27. // Attach menu items to menu
28. menu.add(m1);
29. menu.add(m2);
30. menu.add(m3);
31. // Attach menu items to submenu
32. submenu.add(m4);
33. submenu.add(m5);
34. // Attach submenu to menu
35. menu.add(submenu);
36. // Attach menu to menu bar
37. mbar.add(menu);
38. // Set menu bar to the frame
39. setMenuBar(mbar);
40. }
41. public static void main(String args[])
42. {
43. new AWTMenu();
44. }
45. }

Sample output of this program: