RbMenuItem = new JRadioButtonMenuItem("A radio button menu item") Menu.add(menuItem) menuItem = new JMenuItem(new ImageIcon("images/middle.gif")) Menu.add(menuItem) menuItem = new JMenuItem("Both text and icon", MenuItem.getAccessibleContext().setAccessibleDescription( MenuItem = new JMenuItem("A text-only menu item", "The only menu in this program that has menu items") Menu.getAccessibleContext().setAccessibleDescription( Other required files are listed in the example index.
The bold lines of code create and connect the menu objects the other code sets up or customizes the menu objects. The following code creates the menus shown near the beginning of this menu section. The answer is that when a menu is activated, it automatically brings up a popup menu that displays the menu items. You might be wondering how a menu, if it's only a button, shows its menu items. Here is a picture of the inheritance hierarchy for the menu-related classes:Īs the figure shows, menu items (including menus) are simply buttons. The rest of this section teaches you about the menu components and tells you how to use various menu features: You can also specify other properties, such as font and color. As you can see, a menu item can have either an image or text, or both. The following figure shows many menu-related components: a menu bar, menus, menu items, radio button menu items, check box menu items, and separators. The popup menu then appears under the cursor. A popup menu is a menu that is invisible until the user makes a platform-specific mouse action, such as pressing the right mouse button, over a popup-enabled component. A menu bar contains one or more menus and has a customary, platform-dependent location usually along the top of a window. Instead, a menu usually appears either in a menu bar or as a popup menu. Menus are unique in that, by convention, they aren't placed with the other components in the UI. If any of your menu items performs an action that is duplicated by another menu item or by a tool-bar button, then in addition to this section you should read
Other components with which the user can make a one-of-many choice include combo boxes, lists, radio buttons, spinners, and tool bars. A menu provides a space-saving way to let the user choose one of several options.
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