Java AWT menus and menu bars

31 Oct 2023

In Java, the Abstract Window Toolkit (AWT) provides a set of classes and methods for creating graphical user interfaces (GUIs). One of the essential components of GUIs is menus and menu bars, which allow users to navigate and perform various actions in an application. In this blog post, we will explore how to create menus and menu bars using Java AWT.

What are Menus and Menu Bars?
Creating Menus
Creating Menu Bars
Adding Actions to Menu Items
Conclusion
References

Menus and menu bars are common UI elements used in GUI applications to display a list of options or actions available to the user. Menus typically appear as dropdown lists or popup windows when the user interacts with a specific UI component, such as clicking on a button or selecting an option from a menu bar.

Menu bars, on the other hand, are horizontal bars displayed at the top of a window or frame that contain multiple menus. They provide a convenient way for users to access various functionalities and sub-menus within an application.

Creating Menus

To create a menu in Java AWT, you need to use the Menu class. Here’s an example code snippet that demonstrates how to create a menu and add it to a frame:

import java.awt.*;

public class MenuExample extends Frame {
   public MenuExample() {
      setTitle("Java AWT Menu Example");
      setSize(300, 200);

      MenuBar menuBar = new MenuBar();
      Menu menu = new Menu("File");
      menu.add(new MenuItem("New"));
      menu.add(new MenuItem("Open"));
      menu.add(new MenuItem("Save"));
      menuBar.add(menu);
      setMenuBar(menuBar);

      setVisible(true);
   }

   public static void main(String[] args) {
      new MenuExample();
   }
}

In the above code, we create an instance of the Menu class and add MenuItem objects to it. These MenuItem objects represent the individual options available in the menu. We then add the menu to a MenuBar and set it as the menu bar of the frame using the setMenuBar() method.

To create a menu bar in Java AWT, you need to use the MenuBar class. Here’s an example code snippet that demonstrates how to create a menu bar and add it to a frame:

import java.awt.*;

public class MenuBarExample extends Frame {
   public MenuBarExample() {
      setTitle("Java AWT Menu Bar Example");
      setSize(300, 200);

      MenuBar menuBar = new MenuBar();
      Menu menu1 = new Menu("File");
      menu1.add(new MenuItem("New"));
      menu1.add(new MenuItem("Open"));
      menu1.add(new MenuItem("Save"));

      Menu menu2 = new Menu("Edit");
      menu2.add(new MenuItem("Cut"));
      menu2.add(new MenuItem("Copy"));
      menu2.add(new MenuItem("Paste"));

      menuBar.add(menu1);
      menuBar.add(menu2);
      setMenuBar(menuBar);

      setVisible(true);
   }

   public static void main(String[] args) {
      new MenuBarExample();
   }
}

In the above code, we create two instances of the Menu class (menu1 and menu2) and add MenuItem objects to each of them. We then add both menus to the MenuBar and set it as the menu bar of the frame using the setMenuBar() method.

To add actions or event listeners to the menu items, you need to use the addActionListener() method and implement the ActionListener interface. Here’s an example code snippet that demonstrates how to add an action to a menu item:

import java.awt.*;
import java.awt.event.*;

public class MenuItemActionExample extends Frame implements ActionListener {
   public MenuItemActionExample() {
      setTitle("Java AWT Menu Item Action Example");
      setSize(300, 200);

      MenuBar menuBar = new MenuBar();
      Menu menu = new Menu("File");

      MenuItem newItem = new MenuItem("New");
      newItem.addActionListener(this);
      menu.add(newItem);

      MenuItem openItem = new MenuItem("Open");
      openItem.addActionListener(this);
      menu.add(openItem);

      MenuItem saveItem = new MenuItem("Save");
      saveItem.addActionListener(this);
      menu.add(saveItem);

      menuBar.add(menu);
      setMenuBar(menuBar);

      setVisible(true);
   }

   public void actionPerformed(ActionEvent e) {
      String command = e.getActionCommand();

      if (command.equals("New")) {
         // Perform 'New' action
      } else if (command.equals("Open")) {
         // Perform 'Open' action
      } else if (command.equals("Save")) {
         // Perform 'Save' action
      }
   }

   public static void main(String[] args) {
      new MenuItemActionExample();
   }
}

In the above code, we implement the ActionListener interface and override the actionPerformed() method to handle the actions performed on the menu items. When a menu item is clicked, the actionPerformed() method is invoked, and we can determine which menu item triggered the action using the getActionCommand() method.

Conclusion

Menus and menu bars are essential components in GUI applications that provide users with a convenient way to access various functionalities. In this blog post, we explored how to create menus and menu bars using Java AWT. We also learned how to add actions to menu items to perform specific tasks. By understanding these concepts, you can enhance the user experience of your Java applications.

Table of Contents

What are Menus and Menu Bars?

Creating Menus

Creating Menu Bars

Adding Actions to Menu Items

Conclusion

References