home | O'Reilly's CD bookshelfs | FreeBSD | Linux | Cisco | Cisco Exam  

Java AWT

Previous Chapter 10
Would You Like to Choose from the Menu?

10.3 MenuShortcut

MenuShortcut is a class used to represent a keyboard shortcut for a MenuItem. When these events occur, an action event is generated that triggers the menu component. When a shortcut is associated with a MenuItem, the MenuItem automatically displays a visual clue, which indicates that a keyboard accelerator is available.

MenuShortcut Methods


public MenuShortcut (int key) (New)

The first MenuShortcut constructor creates a MenuShortcut with key as its designated hot key. The key parameter can be any of the virtual key codes from the KeyEvent class (e.g., VK_A, VK_B, etc.). These constants are listed in Table 4.4. To use the shortcut, the user must combine the given key with a platform-specific modifier key. On Windows and Motif platforms, the modifier is the Control key; on the Macintosh, it is the Command key. For example, if the shortcut key is F1 (VK_F1) and you're using Windows, you would press Ctrl+F1 to execute the shortcut. To find out the platform's modifier key, call the Toolkit.getMenuShortcutKeyMask() method.

public MenuShortcut(int key, boolean useShiftModifier) (New)

This MenuShortcut constructor creates a MenuShortcut with key as its designated hot key. If useShiftModifier is true, the Shift key must be depressed for this shortcut to trigger the action event (in addition to the shortcut key). The key parameter represents the integer value of a KEY_PRESS event, so in addition to ASCII values, possible values include the various Event keyboard constants (listed in Table 4.2) like Event.F1, Event.HOME, and Event.PAUSE. For example, if key is the ASCII value for A and useShiftModifier is true, the shortcut key is Shift+Ctrl+A on a Windows/Motif platform.

Miscellaneous methods

public int getKey () (New)

The getKey() method retrieves the virtual key code for the key that triggered this MenuShortcut. The virtual key codes are the VK constants defined by the KeyEvent class (see Table 4.4).

public boolean usesShiftModifier() (New)

The usesShiftModifier() method returns true if this MenuShortcut requires the Shift key be pressed, false otherwise.

public boolean equals(MenuShortcut s) (New)

The equals() method overrides Object's equals() method to define equality for menu shortcuts. Two MenuShortcut objects are equal if their key and useShiftModifier values are equal.

protected String paramString () (New)

The paramString() method of MenuShortcut helps build up a string describing the shortcut; it appends the shortcut key and a shift modifier indicator to the string under construction. Oddly, this method is not currently used, nor can you call it; MenuShortcut has its own toString() method that does the job itself.

public String toString() (New)

The toString() method of MenuShortcut builds a String to display the contents of the MenuShortcut.

Previous Home Next
MenuContainer Book Index MenuItem

Java in a Nutshell Java Language Reference Java AWT Java Fundamental Classes Exploring Java