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Chapter 10 Would You Like to Choose from the Menu? |
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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.
Constructors
- public MenuShortcut (int key)
-
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)
-
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 ()
-
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()
-
The usesShiftModifier() method
returns true if this MenuShortcut
requires the Shift key be pressed, false
otherwise.
- public boolean equals(MenuShortcut s)
-
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 ()
-
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()
-
The toString() method of MenuShortcut
builds a String to display
the contents of the MenuShortcut.
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