public class ActiveCheckboxMenuItem extends CheckboxMenuItem implements CSProcess
java.awt.CheckboxMenuItem
with a channel interface.
All channels are optional. The configure and event channels are settable from a constructor. The event channel delivers the generated java.awt.ItemEvent whenever the ActiveCheckboxMenuItem is selected. Other event channels can be added to notify the occurrence of any other events the component generates (by calling the appropriate addXXXEventChannel method before the process is run). Messages can be sent down the configure channel at any time to configure the component. See the table below for details.
All channels are managed by independent internal handler processes. It is, therefore, safe for a serial application process both to service an event channel and configure the component -- no deadlock can occur.
IMPORTANT: it is essential that event channels from this process are always serviced -- otherwise the Java Event Thread will be blocked and the GUI will stop responding. A simple way to guarantee this is to use channels configured with overwriting buffers. For example:
final One2OneChannel myCheckboxMenuItemEvent = Channel.one2one (new OverWriteOldestBuffer (n)); final ActiveCheckboxMenuItem myCheckboxMenuItem = new ActiveCheckboxMenuItem (null, myCheckboxMenuItemEvent.out (), "Choose Me");This will ensure that the Java Event Thread will never be blocked. Slow or inattentive readers may miss rapidly generated events, but the n most recent events will always be available.
Input Channels | ||
---|---|---|
configure | String | Change the label on the ActiveCheckboxMenuItem to the value of the String |
java.awt.MenuShortcut | Sets the MenuShortcut for the ActiveCheckboxMenuItem | |
Boolean |
|
|
ActiveCheckboxMenuItem.Configure | Invoke the user-defined Configure.configure method on the checkboxMenuItem. | |
Output Channels | ||
event | java.awt.ItemEvent | The generated java.awt.ItemEvent is written down this channel (when the checkboxMenuItem is selected or deslected) |
actionEvent | ActionEvent | See the addActionEventChannel method. |
import java.awt.*; import java.awt.event.*; import org.jcsp.lang.*; import org.jcsp.util.*; import org.jcsp.awt.*; public class ActiveCheckboxMenuItemExample { public static void main (String argv[]) { final ActiveClosingFrame activeClosingFrame = new ActiveClosingFrame ("ActiveCheckboxMenuItem Example"); final ActiveFrame frame = activeClosingFrame.getActiveFrame (); final MenuBar menuBar = new MenuBar (); frame.setMenuBar (menuBar); final Menu fileMenu = new Menu ("File"); final Menu langMenu = new Menu ("Language"); menuBar.add (fileMenu); menuBar.add (langMenu); final String[] fileOptions = {"Hello World", "Rocket Science", "CSP", "Monitors", "Ignore Me", "Goodbye World"}; final String[] langOptions = {"occam-pi", "Java", "Smalltalk", "Algol-60", "Pascal", "Haskell", "SML", "Lisp"}; final Any2OneChannel event[] = Channel.any2oneArray (2, new OverWriteOldestBuffer (10)); final ActiveMenuItem[] fileMenuItem = new ActiveMenuItem[fileOptions.length]; for (int i = 0; i < fileOptions.length; i++) { fileMenuItem[i] = new ActiveMenuItem (null, event[0].out (), fileOptions[i]); fileMenu.add (fileMenuItem[i]); } final ActiveCheckboxMenuItem[] langCheckboxMenuItem = new ActiveCheckboxMenuItem[langOptions.length]; for (int i = 0; i < langOptions.length; i++) { langCheckboxMenuItem[i] = new ActiveCheckboxMenuItem (null, event[1].out (), langOptions[i]); langMenu.add (langCheckboxMenuItem[i]); } frame.setSize (300, 200); frame.setBackground (Color.green); frame.setVisible (true); new Parallel ( new CSProcess[] { activeClosingFrame, new Parallel (fileMenuItem), new Parallel (langCheckboxMenuItem), new CSProcess () { public void run () { boolean running = true; while (running) { final String s = (String) event[0].in ().read (); System.out.println ("File ==> `" + s + "' selected ..."); running = (s != fileOptions[fileOptions.length - 1]); } frame.setVisible (false); System.exit (0); } }, new CSProcess () { public void run () { while (true) { final ItemEvent e = (ItemEvent) event[1].in ().read (); final String item = (String) e.getItem (); System.out.print ("Language ==> `" + item); if (e.getStateChange () == ItemEvent.SELECTED) { System.out.println ("' selected ..."); } else { System.out.println ("' deselected ..."); } } } } } ).run (); } }
CheckboxMenuItem
,
ComponentEvent
,
FocusEvent
,
KeyEvent
,
MouseEvent
,
OverWriteOldestBuffer
,
Serialized FormModifier and Type | Class and Description |
---|---|
static interface |
ActiveCheckboxMenuItem.Configure
This enables general configuration of this component.
|
CheckboxMenuItem.AccessibleAWTCheckboxMenuItem
MenuItem.AccessibleAWTMenuItem
MenuComponent.AccessibleAWTMenuComponent
Constructor and Description |
---|
ActiveCheckboxMenuItem()
Constructs a new unchecked ActiveCheckboxMenuItem with no initial label
and no configuration or event channels.
|
ActiveCheckboxMenuItem(ChannelInput configure,
ChannelOutput event)
Constructs a new unchecked ActiveCheckboxMenuItem with no initial label.
|
ActiveCheckboxMenuItem(ChannelInput configure,
ChannelOutput event,
String s)
Constructs a new unchecked ActiveCheckboxMenuItem.
|
ActiveCheckboxMenuItem(ChannelInput configure,
ChannelOutput event,
String s,
boolean state)
Constructs a new ActiveCheckboxMenuItem.
|
ActiveCheckboxMenuItem(String s)
Constructs a new unchecked ActiveCheckboxMenuItem
with no configuration or event channels.
|
ActiveCheckboxMenuItem(String s,
boolean state)
Constructs a new ActiveCheckboxMenuItem
with no configuration or event channels.
|
Modifier and Type | Method and Description |
---|---|
void |
addActionEventChannel(ChannelOutput actionEvent)
Add a new channel to this component that will be used to notify that
an ActionEvent has occurred.
|
void |
run()
The main body of this process.
|
void |
setConfigureChannel(ChannelInput configure)
Sets the configuration channel for this ActiveCheckboxMenuItem.
|
addItemListener, addNotify, getAccessibleContext, getItemListeners, getListeners, getSelectedObjects, getState, paramString, processEvent, processItemEvent, removeItemListener, setState
addActionListener, deleteShortcut, disable, disableEvents, enable, enable, enableEvents, getActionCommand, getActionListeners, getLabel, getShortcut, isEnabled, processActionEvent, removeActionListener, setActionCommand, setEnabled, setLabel, setShortcut
dispatchEvent, getFont, getName, getParent, getPeer, getTreeLock, postEvent, removeNotify, setFont, setName, toString
public ActiveCheckboxMenuItem()
public ActiveCheckboxMenuItem(String s)
s
- the initial label displayed on the checkboxMenuItem.public ActiveCheckboxMenuItem(String s, boolean state)
s
- the initial label displayed on the checkboxMenuItem.state
- the initial state of the checkboxMenuItem.public ActiveCheckboxMenuItem(ChannelInput configure, ChannelOutput event)
configure
- the channel for configuration events
-- can be null if no configuration is required.event
- the current label will be output when the checkboxMenuItem is selected
-- can be null if no notification is required.public ActiveCheckboxMenuItem(ChannelInput configure, ChannelOutput event, String s)
configure
- the channel for configuration events
-- can be null if no configuration is required.event
- the current label will be output when the checkboxMenuItem is selected
-- can be null if no notification is required.s
- the initial label displayed on the checkboxMenuItem.public ActiveCheckboxMenuItem(ChannelInput configure, ChannelOutput event, String s, boolean state)
configure
- the channel for configuration events
-- can be null if no configuration is required.event
- the current label will be output when the checkboxMenuItem is selected
-- can be null if no notification is required.s
- the initial label displayed on the checkboxMenuItem.state
- the initial state of the checkboxMenuItem.public void setConfigureChannel(ChannelInput configure)
configure
- the channel for configuration events
-- can be null if no configuration is required.public void addActionEventChannel(ChannelOutput actionEvent)
NOTE: This method must be called before this process is run.
actionEvent
- the channel down which to send ActionEvents.Copyright © 1996–2015. All rights reserved.