org.openide.util.actions

Class SystemAction

java.lang.Object

org.openide.util.SharedClassObject

org.openide.util.actions.SystemAction

All Implemented Interfaces:

ActionListener, Externalizable, Serializable, EventListener, Action, HelpCtx.Provider

Direct Known Subclasses:

BooleanStateAction, CallableSystemAction

public abstract class SystemAction
extends SharedClassObject
implements Action, HelpCtx.Provider

A base class for user-visible actions.

Implements the Swing Action interface to enable use with the Swing action model.

An action class is a singleton, i.e. should generally contain no instance state. Rather, subclassing and use of abstract protected methods should be used to create variants of the action.

While it is possible to subclass this class directly--for example, if your "action" is really a placeholder for a popup menu that shows other actions--most people will prefer to use one of the subclasses, which are more convenient.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static String	PROP_ENABLED Name of property indicating whether or not the action is enabled.
static String	PROP_ICON Name of property for the action's display icon.

Fields inherited from interface javax.swing.Action

ACCELERATOR_KEY, ACTION_COMMAND_KEY, DEFAULT, DISPLAYED_MNEMONIC_INDEX_KEY, LARGE_ICON_KEY, LONG_DESCRIPTION, MNEMONIC_KEY, NAME, SELECTED_KEY, SHORT_DESCRIPTION, SMALL_ICON

Constructor Summary

Constructors

Constructor and Description
SystemAction()

Method Summary

Modifier and Type	Method and Description
abstract void	actionPerformed(ActionEvent ev) Actually perform the action.
protected boolean	clearSharedData() Indicate whether action state should be cleared after the last action of this class is deleted.
static JPopupMenu	createPopupMenu(SystemAction[] actions) Deprecated. Use Utilities.actionsToPopup(javax.swing.Action[], org.openide.util.Lookup)
static JToolBar	createToolbarPresenter(SystemAction[] actions) Create the default toolbar representation of an array of actions.
static <T extends SystemAction> T	get(Class<T> actionClass) Obtain a singleton instance of the action with a specified class.
abstract HelpCtx	getHelpCtx() Get a help context for the action.
Icon	getIcon() Get the action's display icon.
Icon	getIcon(boolean createLabel) Get the action's display icon, possibly creating a text label.
abstract String	getName() Get a human presentable name of the action.
Object	getValue(String name) Get a property in the singleton.
protected String	iconResource() Specify the proper resource name for the action's icon.
protected void	initialize() Initialize the action.
boolean	isEnabled() Test whether the action is currently enabled.
static SystemAction[]	linkActions(SystemAction[] actions1, SystemAction[] actions2) Concatenate two arrays of actions.
void	putValue(String name, Object value) Set a property in the singleton.
void	setEnabled(boolean value) Set whether the action should be enabled.
void	setIcon(Icon icon) Set the action's display icon.

Methods inherited from class org.openide.util.SharedClassObject

addNotify, addPropertyChangeListener, equals, finalize, findObject, findObject, firePropertyChange, getLock, getProperty, hashCode, putProperty, putProperty, readExternal, removeNotify, removePropertyChangeListener, reset, writeExternal, writeReplace

Methods inherited from class java.lang.Object

clone, getClass, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface javax.swing.Action

accept, addPropertyChangeListener, removePropertyChangeListener

Field Detail

PROP_ENABLED

public static final String PROP_ENABLED

Name of property indicating whether or not the action is enabled.

See Also:

Constant Field Values

PROP_ICON

public static final String PROP_ICON

Name of property for the action's display icon.

See Also:

Constant Field Values

Constructor Detail

SystemAction

public SystemAction()

Method Detail

get

public static <T extends SystemAction> T get(Class<T> actionClass)

Obtain a singleton instance of the action with a specified class. If there already is a instance then it is returned, otherwise a new one is created.

Parameters:

actionClass - the class of the action to find

Returns:

the singleton action instance

Throws:

ClassCastException - if the class is not SystemAction

IllegalArgumentException - if the instance cannot be created

getName

public abstract String getName()

Get a human presentable name of the action. This may be presented as an item in a menu.

Using the normal menu presenters, an included ampersand before a letter will be treated as the name of a mnemonic.

Returns:

the name of the action

getHelpCtx

public abstract HelpCtx getHelpCtx()

Get a help context for the action.

Specified by:

getHelpCtx in interface HelpCtx.Provider

Returns:

the help context for this action

isEnabled

public boolean isEnabled()

Test whether the action is currently enabled.

Specified by:

isEnabled in interface Action

Returns:

true if so

setEnabled

public void setEnabled(boolean value)

Set whether the action should be enabled.

Specified by:

setEnabled in interface Action

Parameters:

value - true to enable it

putValue

public final void putValue(String name,
                           Object value)

Set a property in the singleton. This property is common for all instances of the same class.

Specified by:

putValue in interface Action

Parameters:

name - the name of the property

value - the value

getValue

public final Object getValue(String name)

Get a property in the singleton. Values are shared among all instances of the same class. The special tokens Action.NAME, Action.SMALL_ICON and "iconBase" are also recognized and delegated to SystemAction.getName(), SystemAction.getIcon() and SystemAction.iconResource() resp.

Specified by:

getValue in interface Action

Parameters:

name - the name of the property

Returns:

the value

actionPerformed

public abstract void actionPerformed(ActionEvent ev)

Actually perform the action. Specified in ActionListener.actionPerformed(java.awt.event.ActionEvent).

In some cases, the implementation may have an empty body, if the presenters handle the performing of the action in a different way than by calling this method.

Since 4.11, will be performed directly in the event thread.

Specified by:

actionPerformed in interface ActionListener

Parameters:

ev - the event triggering the action

initialize

protected void initialize()

Initialize the action. The default implementation just enabled it.

Overrides:

initialize in class SharedClassObject

clearSharedData

protected boolean clearSharedData()

Indicate whether action state should be cleared after the last action of this class is deleted.

Overrides:

clearSharedData in class SharedClassObject

Returns:

false in the default implementation

setIcon

public final void setIcon(Icon icon)

Set the action's display icon.

Parameters:

icon - the icon

getIcon

public final Icon getIcon()

Get the action's display icon.

Returns:

the icon

Throws:

IllegalStateException - if an icon could not be created

getIcon

public final Icon getIcon(boolean createLabel)

Get the action's display icon, possibly creating a text label.

Parameters:

createLabel - if true, create a textual icon if otherwise there would be none; if false, create a blank icon

Returns:

an icon

Throws:

IllegalStateException - if an icon could not be created

iconResource

protected String iconResource()

Specify the proper resource name for the action's icon. May be overridden by subclasses; the default is to have no icon. Typically this should be a 16x16 color GIF. Do not use relative paths nor an initial slash. If e.g. myIcon.gif is accompanied with myIcon_pressed.gif, myIcon_disabled.gif and/or myIcon_rollover.gif these images are used to call methods on JButton.setPressedIcon(), JButton.setDisabledIcon() and/or JButton.setRolloverIcon() with appropriate images. Please check Actions.connect for additional info how this is achieved (using special "iconBase" key for getValue). As of APIs version 3.24, this path will be used for a localized search automatically. If you do not want an icon, do not override this to return a blank icon. Leave it null, but call putValue("noIconInMenu", Boolean.TRUE) to make sure that no extra space is allotted for an icon in the menu item.

Returns:

the resource name for the icon, e.g. com/mycom/mymodule/myIcon.gif; or null to have no icon (make a text label)

createToolbarPresenter

public static JToolBar createToolbarPresenter(SystemAction[] actions)

Create the default toolbar representation of an array of actions. Null items in the array will add a separator to the toolbar.

Parameters:

actions - actions to show in the generated toolbar

Returns:

a toolbar instance displaying them

linkActions

public static SystemAction[] linkActions(SystemAction[] actions1,
                                         SystemAction[] actions2)

Concatenate two arrays of actions.

Parameters:

actions1 - first array of actions to link

actions2 - second array of actions to link

Returns:

an array of both sets of actions in the same order

createPopupMenu

@Deprecated
public static JPopupMenu createPopupMenu(SystemAction[] actions)

Deprecated. Use Utilities.actionsToPopup(javax.swing.Action[], org.openide.util.Lookup)

Create the default popup menu representation of an array of actions.

Parameters:

actions - actions to show in the generated menu

Returns:

a popup menu displaying them