| /* |
| * Copyright 2008 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.event.logical.shared; |
| |
| import com.google.gwt.event.shared.GwtEvent; |
| |
| /** |
| * Represents a selection event. |
| * |
| * @param <T> the type being selected |
| */ |
| public class SelectionEvent<T> extends GwtEvent<SelectionHandler<T>> { |
| |
| /** |
| * Handler type. |
| */ |
| private static Type<SelectionHandler<?>> TYPE; |
| |
| /** |
| * Fires a selection event on all registered handlers in the handler |
| * manager.If no such handlers exist, this method will do nothing. |
| * |
| * @param <T> the selected item type |
| * @param source the source of the handlers |
| * @param selectedItem the selected item |
| */ |
| public static <T> void fire(HasSelectionHandlers<T> source, T selectedItem) { |
| if (TYPE != null) { |
| SelectionEvent<T> event = new SelectionEvent<T>(selectedItem); |
| source.fireEvent(event); |
| } |
| } |
| |
| /** |
| * Gets the type associated with this event. |
| * |
| * @return returns the handler type |
| */ |
| public static Type<SelectionHandler<?>> getType() { |
| if (TYPE == null) { |
| TYPE = new Type<SelectionHandler<?>>(); |
| } |
| return TYPE; |
| } |
| |
| private final T selectedItem; |
| |
| /** |
| * Creates a new selection event. |
| * |
| * @param selectedItem selected item |
| */ |
| protected SelectionEvent(T selectedItem) { |
| this.selectedItem = selectedItem; |
| } |
| |
| // The instance knows its BeforeSelectionHandler is of type I, but the TYPE |
| // field itself does not, so we have to do an unsafe cast here. |
| @SuppressWarnings("unchecked") |
| @Override |
| public final Type<SelectionHandler<T>> getAssociatedType() { |
| return (Type) TYPE; |
| } |
| |
| /** |
| * Gets the selected item. |
| * |
| * @return the selected item |
| */ |
| public T getSelectedItem() { |
| return selectedItem; |
| } |
| |
| @Override |
| protected void dispatch(SelectionHandler<T> handler) { |
| handler.onSelection(this); |
| } |
| } |