com.google.gwt.event.logical.shared.SelectionEvent Maven / Gradle / Ivy
/*
* 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 the type being selected
*/
public class SelectionEvent extends GwtEvent> {
/**
* Handler type.
*/
private static Type> TYPE;
/**
* Fires a selection event on all registered handlers in the handler
* manager.If no such handlers exist, this method will do nothing.
*
* @param the selected item type
* @param source the source of the handlers
* @param selectedItem the selected item
*/
public static void fire(HasSelectionHandlers source, T selectedItem) {
if (TYPE != null) {
SelectionEvent event = new SelectionEvent(selectedItem);
source.fireEvent(event);
}
}
/**
* Gets the type associated with this event.
*
* @return returns the handler type
*/
public static Type> getType() {
if (TYPE == null) {
TYPE = new Type>();
}
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> getAssociatedType() {
return (Type) TYPE;
}
/**
* Gets the selected item.
*
* @return the selected item
*/
public T getSelectedItem() {
return selectedItem;
}
@Override
protected void dispatch(SelectionHandler handler) {
handler.onSelection(this);
}
}