Package org.eclipse.ui

Class SelectionListenerFactory

java.lang.Object

org.eclipse.ui.SelectionListenerFactory

public class SelectionListenerFactory
extends Object

Selection listeners are notified of all selections in the workbench. This means that the listener is always required to filter unwanted selections. In addition, the listener has to make sure not to waste cycles in the UI thread, for instance, not update the UI while it is invisible, but make sure to repaint if becoming visible.

This filtering generally requires a lot of boilerplate code while, ideally, you only want to receive selections that are of interest.

This factory takes care of many practical filtering scenarios by allowing the creation of an intermediate selection service that only calls you back with selections you can work with.

Usage: (assumes the part implements ISelectionListener)

Only visit the listener if our part is visible:

 getSite().getPage().addSelectionListener(SelectionListenerFactory.createVisibleListener(this, this));
 

Only visit the listener if our part is visible and the selection did not come from us:

 getSite().getPage().addSelectionListener(SelectionListenerFactory.createVisibleSelfMutedListener(this, this));
 

Chaining predicates:

 import static org.eclipse.ui.SelectionListenerFactory.Predicates.adaptsTo;
 import static org.eclipse.ui.SelectionListenerFactory.Predicates.selectionPartVisible;
 import static org.eclipse.ui.SelectionListenerFactory.Predicates.selectionSize;
 import static org.eclipse.ui.SelectionListenerFactory.Predicates.selfMute;
 import static org.eclipse.ui.SelectionListenerFactory.Predicates.targetPartVisible;

 Predicate<ISelectionModel> predicate = adaptsTo(PlatformObject.class))
                .and(selectionSize(1))
                .and(selfMute)
                .and(selectionPartVisible)
                .and(targetPartVisible));

 getSite().getPage().addSelectionListener(SelectionListenerFactory.createListener(this, predicate));
 

Creating your own predicate in combination with the visible part predicate:

 Predicate<ISelectionModel> predicate = new Predicate<>() {

        public boolean test(ISelectionModel model) {
                if (model.getCurrentSelectionPart() == SampleView4.this) {
                        return false;
                }
                if (!(model.getCurrentSelectionPart() instanceof SampleView)) {
                        return false;
                }
                return true;
        }
 };

 GetSite().getPage().addSelectionListener(SelectionListenerFactory.createVisibleListener(this, this, predicate));
 

Since:

3.117

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	SelectionListenerFactory.ISelectionModel	A model containing selection values.
static class	SelectionListenerFactory.Predicates	Static class to hold the predicates for this factory.

Constructor Summary

Constructors

Constructor	Description
SelectionListenerFactory()

Method Summary

Modifier and Type	Method	Description
static ISelectionListener	createListener(IWorkbenchPart part, Predicate<SelectionListenerFactory.ISelectionModel> predicate)	Create a listener for a part that also acts as the selection listener.
static ISelectionListener	createListener(IWorkbenchPart part, ISelectionListener listener, Predicate<SelectionListenerFactory.ISelectionModel> predicate)	Create a listener for a part with a separate selection listener.
static ISelectionListener	createVisibleListener(IWorkbenchPart part, ISelectionListener listener)	Convenience method to create a listener that only gets notified when: the selection has changed; the part is visible.
static ISelectionListener	createVisibleListener(IWorkbenchPart part, ISelectionListener listener, Predicate<SelectionListenerFactory.ISelectionModel> additionalPredicate)	Convenience method to create a listener that only gets notified when: the selection has changed; the part is visible.
static ISelectionListener	createVisibleSelfMutedListener(IWorkbenchPart part, ISelectionListener listener)	Provides a listener that only gets notified of selection events when: the selection was not already delivered from any part; the part is visible; the selection does not originate from the part.
static ISelectionListener	createVisibleSelfMutedListener(IWorkbenchPart part, ISelectionListener listener, Predicate<SelectionListenerFactory.ISelectionModel> additionalPredicate)	Provides a listener that only gets notified of selection events when: the selection has changed; the part is visible; the selection does not originate from the part.
static ISelectionListener	decorate(ISelectionListener listener, Predicate<SelectionListenerFactory.ISelectionModel> additionalPredicate)	Decorates the passed listener with the passed predicate.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

SelectionListenerFactory

public SelectionListenerFactory()

Method Details

createListener

public static ISelectionListener createListener(IWorkbenchPart part,
 Predicate<SelectionListenerFactory.ISelectionModel> predicate)

Create a listener for a part that also acts as the selection listener.

The listener will be automatically removed when the part is closed.

Parameters:

part - the part which must implements the ISelectionListener to be notified. May not be null.

predicate - the predicate must test true before the selection is delivered. May not be null.

Returns:

the listener. Never null.

createListener

public static ISelectionListener createListener(IWorkbenchPart part,
 ISelectionListener listener,
 Predicate<SelectionListenerFactory.ISelectionModel> predicate)

Create a listener for a part with a separate selection listener.

The listener will be automatically removed when the part is closed.

Parameters:

part - the part. May not be null.

listener - the selection listener to be notified. May not be null. It can be the part itself if it implements ISelectionChangedListener.

predicate - the predicate that must test true before the selection is delivered. May not be null.

Returns:

the listener

createVisibleListener

public static ISelectionListener createVisibleListener(IWorkbenchPart part,
 ISelectionListener listener)

Convenience method to create a listener that only gets notified when:

• the selection has changed;
• the part is visible.

The listener will be automatically removed when the part is closed.

Parameters:

part - the part. May not be null.

listener - the selection listener to be notified. May not be null. It can be the part itself if it implements ISelectionChangedListener.

Returns:

the listener. Never null.

See Also:

• SelectionListenerFactory.Predicates.alreadyDelivered
• SelectionListenerFactory.Predicates.targetPartVisible

createVisibleListener

public static ISelectionListener createVisibleListener(IWorkbenchPart part,
 ISelectionListener listener,
 Predicate<SelectionListenerFactory.ISelectionModel> additionalPredicate)

Convenience method to create a listener that only gets notified when:

• the selection has changed;
• the part is visible.

The listener will be automatically removed when the part is closed.

Parameters:

part - the part. May not be null.

listener - the selection listener to be notified. May not be null. It can be the part itself if it implements ISelectionChangedListener.

additionalPredicate - the additional predicate which must test true before the selection is delivered. May not be null.

Returns:

the listener, never null.

See Also:

• SelectionListenerFactory.Predicates.alreadyDelivered
• SelectionListenerFactory.Predicates.targetPartVisible

createVisibleSelfMutedListener

public static ISelectionListener createVisibleSelfMutedListener(IWorkbenchPart part,
 ISelectionListener listener)

Provides a listener that only gets notified of selection events when:

• the selection was not already delivered from any part;
• the part is visible;
• the selection does not originate from the part.

The listener will be automatically removed when the part is closed.

Parameters:

part - the part. May not be null.

listener - the selection listener to be notified. It can be the part itself if it implements ISelectionChangedListener. May not be null.

Returns:

the listener, never null.

See Also:

• SelectionListenerFactory.Predicates.alreadyDeliveredAnyPart
• SelectionListenerFactory.Predicates.targetPartVisible
• SelectionListenerFactory.Predicates.selfMute

createVisibleSelfMutedListener

public static ISelectionListener createVisibleSelfMutedListener(IWorkbenchPart part,
 ISelectionListener listener,
 Predicate<SelectionListenerFactory.ISelectionModel> additionalPredicate)

Provides a listener that only gets notified of selection events when:

• the selection has changed;
• the part is visible;
• the selection does not originate from the part.

The listener will be automatically removed if the part is closed.

Parameters:

part - the part. May not be null.

listener - the selection listener to be notified. May not be null. It can be the part itself if it implements ISelectionChangedListener.

additionalPredicate - the predicate to and-add on top of the chain that this method already adds. May not be null

Returns:

the listener, never null.

See Also:

• createVisibleListener(IWorkbenchPart, ISelectionListener)
• SelectionListenerFactory.Predicates.alreadyDeliveredAnyPart
• SelectionListenerFactory.Predicates.targetPartVisible
• SelectionListenerFactory.Predicates.selfMute

decorate

public static ISelectionListener decorate(ISelectionListener listener,
 Predicate<SelectionListenerFactory.ISelectionModel> additionalPredicate)

Decorates the passed listener with the passed predicate. The listener must be created by this factory otherwise nothing happens.

Parameters:

listener - the listener that was created by this factory.

additionalPredicate - a predicate to and-add on top of the chain that the listener already has. May not be null.

Returns:

the passed listener