org.eclipse.gef4.common.activate

Interface IActivatable

All Superinterfaces:

IPropertyChangeNotifier

public interface IActivatable
extends IPropertyChangeNotifier

An IActivatable represents an entity that can be activated ( activate()) and deactivated (deactivate()) as required.

The current activation state of an IActivatable (whether the entity is active or not) can be queried by clients (isActive()), and it is expected that an IActivatable notifies registered PropertyChangeListeners about changes of its activation state by means of PropertyChangeEvents, using the property name "active".

Any client implementing this interface may internally use an ActivatableSupport as a delegate to easily realize the required functionality.

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	ACTIVE_PROPERTY A key used as PropertyChangeEvent.getPropertyName() when notifying about changes of the activation state.

Method Summary

Modifier and Type	Method and Description
void	activate() Activates the IActivatable.
void	deactivate() Deactivates the IActivatable.
boolean	isActive() Reports whether this IActivatable is active or inactive.

Methods inherited from interface org.eclipse.gef4.common.properties.IPropertyChangeNotifier

addPropertyChangeListener, removePropertyChangeListener

Field Detail

ACTIVE_PROPERTY

static final java.lang.String ACTIVE_PROPERTY

A key used as PropertyChangeEvent.getPropertyName() when notifying about changes of the activation state.

See Also:

Constant Field Values

Method Detail

activate

void activate()

Activates the IActivatable. It is expected that a call to isActive() returns true after this method has been called (unless deactivate() is called to deactivate the IActivatable), and that a PropertyChangeEvent notifying about an activation change is send to all registered PropertyChangeListeners, if the activation state actually changed, i.e. the IActivatable was not active before.

deactivate

void deactivate()

Deactivates the IActivatable. It is expected that a call to isActive() return false after this method has been called (unless {activate() is called to re-activate the IAdaptable, and that a PropertyChangeEvent notifying about an activation change is send to all registered PropertyChangeListeners, if the activation state actually changed, i.e. the IActivatable was active before.

isActive

boolean isActive()

Reports whether this IActivatable is active or inactive.

Returns:

true in case the IActivatable is active, false otherwise.