RevealContentEvent.java

/*
 * Copyright 2012 Cedric Hauber
 *
 *    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 org.jboss.errai.mvp.client.events;

import com.google.gwt.event.shared.GwtEvent;
import com.google.gwt.event.shared.HasHandlers;
import org.jboss.errai.mvp.client.presenters.Presenter;

/**
 * This event is fired by a {@link com.gwtplatform.mvp.client.Presenter} that desires to reveal itself
 * within its parent. It is typically fired in the {@link com.gwtplatform.mvp.client.Presenter#revealInParent()}
 * method. To reveal a presenter at the root of the application, fire either
 * {@link RevealRootContentEvent}, {@link RevealRootLayoutContentEvent} or
 * {@link RevealRootPopupContentEvent} instead.
 * <p />
 * This event is handled by {@link Proxy} classes. Upon handling this
 * event, the proxy <b>first</b> sets the content appropriately in the
 * presenter, and then reveals the presenter.
 *
 * @see RevealRootContentEvent
 * @see RevealRootLayoutContentEvent
 *
 * @author Philippe Beaudoin
 */
public final class RevealContentEvent extends GwtEvent<RevealContentHandler<?>> {

  /**
   * Fires a {@link RevealContentEvent} with a specific {@link com.google.gwt.event.shared.GwtEvent.Type}
   * into a source that has access to an {@link com.google.web.bindery.event.shared.EventBus}.
   *
   * @param source The source that fires this event ({@link com.google.gwt.event.shared.HasHandlers}).
   * @param type The specific event {@link com.google.gwt.event.shared.GwtEvent.Type}, usually defined in the parent presenter
   *             and annotated with {@link com.gwtplatform.mvp.client.annotations.ContentSlot}.
   * @param content The {@link Presenter} that wants to set itself as content in his parent.
   */
  public static void fire(final HasHandlers source,
      final Type<RevealContentHandler<?>> type, final Presenter<?> content) {
    source.fireEvent(new RevealContentEvent(type, content));
  }

  private final Presenter<?> content;

  private final Type<RevealContentHandler<?>> type;

  public RevealContentEvent(Type<RevealContentHandler<?>> type,
      Presenter<?> content) {
    this.type = type;
    this.content = content;
  }

  @Override
  public Type<RevealContentHandler<?>> getAssociatedType() {
    return type;
  }

  public Presenter<?> getContent() {
    return content;
  }

  @Override
  protected void dispatch(RevealContentHandler<?> handler) {
    handler.onRevealContent(this);
  }

}