|
| |
|
| java.lang.Object
 java.awt.MenuComponent
java.awt.MenuItem
java.awt.CheckboxMenuItem
| CheckboxMenuItem | | public class CheckboxMenuItem extends MenuItem implements ItemSelectable(Code) | | This class represents a check box that can be included in a menu.
Clicking on the check box in the menu changes its state from
"on" to "off" or from "off" to "on."
The following picture depicts a menu which contains an instance
of CheckBoxMenuItem:
The item labeled Check shows a check box menu item
in its "off" state.
When a check box menu item is selected, AWT sends an item event to
the item. Since the event is an instance of ItemEvent,
the processEvent method examines the event and passes
it along to processItemEvent. The latter method redirects
the event to any ItemListener objects that have
registered an interest in item events generated by this menu item.
version:
1.44, 08/19/02
author:
Sami Shaio
See Also: java.awt.event.ItemEvent
See Also: java.awt.event.ItemListener
See Also: java.awt.Frame
See Also: java.awt.Menu
See Also: java.awt.MenuBar
See Also: java.awt.PopupMenu
See Also: java.awt.MenuShortcut
since:
JDK1.0 |
| Constructor Summary | |
| public | CheckboxMenuItem()
Create a check box menu item with an empty label. | | public | CheckboxMenuItem(String label)
Create a check box menu item with the specified label. | | public | CheckboxMenuItem(String label, boolean state)
Create a check box menu item with the specified label and state. |
| Method Summary | |
| public synchronized void | addItemListener(ItemListener l)
Adds the specified item listener to receive item events from
this check box menu item. | | public void | addNotify()
Creates the peer of the checkbox item. | | void | doMenuEvent()
| | boolean | eventEnabled(AWTEvent e)
| | public synchronized ItemListener[] | getItemListeners()
Returns an array of all the item listeners
registered on this checkbox menuitem. | | public synchronized Object[] | getSelectedObjects()
Returns the an array (length 1) containing the checkbox menu item
label or null if the checkbox is not selected. | | public boolean | getState()
| | public String | paramString()
Returns the parameter string representing the state of this check
box menu item. | | protected void | processEvent(AWTEvent e)
Processes events on this check box menu item. | | protected void | processItemEvent(ItemEvent e)
Processes item events occurring on this check box menu item by
dispatching them to any registered ItemListener objects.
This method is not called unless item events are
enabled for this menu item. | | public synchronized void | removeItemListener(ItemListener l)
Removes the specified item listener so that it no longer receives
item events from this check box menu item. | | public synchronized void | setState(boolean b)
Sets this check box menu item to the specifed state. |
| CheckboxMenuItem | | public CheckboxMenuItem()(Code) | | Create a check box menu item with an empty label.
The item's state is initially set to "off."
since:
JDK1.1 |
| CheckboxMenuItem | | public CheckboxMenuItem(String label)(Code) | | Create a check box menu item with the specified label.
The item's state is initially set to "off."
Parameters:
label - a string label for the check box menu item,or null for an unlabeled menu item. |
| CheckboxMenuItem | | public CheckboxMenuItem(String label, boolean state)(Code) | | Create a check box menu item with the specified label and state.
Parameters:
label - a string label for the check box menu item, or null for an unlabeled menu item.
Parameters:
state - the initial state of the menu item, wheretrue indicates "on" andfalse indicates "off."
since:
JDK1.1 |
| doMenuEvent | | void doMenuEvent()(Code) | | |
| getSelectedObjects | | public synchronized Object[] getSelectedObjects()(Code) | | Returns the an array (length 1) containing the checkbox menu item
label or null if the checkbox is not selected.
See Also: ItemSelectable |
| getState | | public boolean getState()(Code) | | Determines whether the state of this check box menu item
is "on" or "off."
the state of this check box menu item, wheretrue indicates "on" andfalse indicates "off."
See Also: java.awt.CheckboxMenuItem.setState |
| paramString | | public String paramString()(Code) | | Returns the parameter string representing the state of this check
box menu item. This string is useful for debugging.
the parameter string of this check box menu item. |
| processEvent | | protected void processEvent(AWTEvent e)(Code) | | Processes events on this check box menu item.
If the event is an instance of ItemEvent,
this method invokes the processItemEvent method.
If the event is not an item event,
it invokes processEvent on the superclass.
Check box menu items currently support only item events.
Parameters:
e - the event
See Also: java.awt.event.ItemEvent
See Also: java.awt.CheckboxMenuItem.processItemEvent
since:
JDK1.1 |
| setState | | public synchronized void setState(boolean b)(Code) | | Sets this check box menu item to the specifed state.
The boolean value true indicates "on" while
false indicates "off."
Parameters:
b - the boolean state of thischeck box menu item.
See Also: java.awt.CheckboxMenuItem.getState |
|
|
|