| /* |
| * Copyright 2010 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| * use this file except in compliance with the License. You may obtain a copy of |
| * the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| * License for the specific language governing permissions and limitations under |
| * the License. |
| */ |
| package com.google.gwt.view.client; |
| |
| import com.google.gwt.event.shared.EventHandler; |
| import com.google.gwt.event.shared.GwtEvent; |
| import com.google.gwt.event.shared.HandlerRegistration; |
| import com.google.gwt.event.shared.HasHandlers; |
| |
| /** |
| * Represents a selection change event. |
| */ |
| public class SelectionChangeEvent extends |
| GwtEvent<SelectionChangeEvent.Handler> { |
| |
| /** |
| * Handler interface for {@link SelectionChangeEvent} events. |
| */ |
| public static interface Handler extends EventHandler { |
| |
| /** |
| * Called when a {@link SelectionChangeEvent} is fired. |
| * |
| * @param event the {@link SelectionChangeEvent} that was fired |
| */ |
| void onSelectionChange(SelectionChangeEvent event); |
| } |
| |
| /** |
| * Interface specifying that a class can add |
| * {@code SelectionChangeEvent.Handler}s. |
| */ |
| public interface HasSelectionChangedHandlers extends HasHandlers { |
| /** |
| * Adds a {@link SelectionChangeEvent} handler. |
| * |
| * @param handler the handler |
| * @return {@link HandlerRegistration} used to remove this handler |
| */ |
| HandlerRegistration addSelectionChangeHandler(Handler handler); |
| } |
| |
| /** |
| * Handler type. |
| */ |
| private static Type<SelectionChangeEvent.Handler> TYPE; |
| |
| /** |
| * Fires a selection change event on all registered handlers in the handler |
| * manager. If no such handlers exist, this method will do nothing. |
| * |
| * @param source the source of the handlers |
| */ |
| public static void fire(HasSelectionChangedHandlers source) { |
| if (TYPE != null) { |
| SelectionChangeEvent event = new SelectionChangeEvent(); |
| source.fireEvent(event); |
| } |
| } |
| |
| /** |
| * Gets the type associated with this event. |
| * |
| * @return returns the handler type |
| */ |
| public static Type<SelectionChangeEvent.Handler> getType() { |
| if (TYPE == null) { |
| TYPE = new Type<SelectionChangeEvent.Handler>(); |
| } |
| return TYPE; |
| } |
| |
| /** |
| * Creates a selection change event. |
| */ |
| SelectionChangeEvent() { |
| } |
| |
| @Override |
| public final Type<SelectionChangeEvent.Handler> getAssociatedType() { |
| return TYPE; |
| } |
| |
| @Override |
| protected void dispatch(SelectionChangeEvent.Handler handler) { |
| handler.onSelectionChange(this); |
| } |
| } |