org.geomajas.gwt.client.event.LayerVisibilityHandler Maven / Gradle / Ivy
/*
* This is part of Geomajas, a GIS framework, http://www.geomajas.org/.
*
* Copyright 2008-2013 Geosparc nv, http://www.geosparc.com/, Belgium.
*
* The program is available in open source according to the GNU Affero
* General Public License. All contributions in this program are covered
* by the Geomajas Contributors License Agreement. For full licensing
* details, see LICENSE.txt in the project root.
*/
package org.geomajas.gwt.client.event;
import org.geomajas.annotation.Api;
import org.geomajas.annotation.UserImplemented;
import com.google.gwt.event.shared.EventHandler;
import com.google.web.bindery.event.shared.Event.Type;
/**
* Interface for handling layer visibility events.
*
* @author Pieter De Graef
* @since 1.0.0
*/
@Api(allMethods = true)
@UserImplemented
public interface LayerVisibilityHandler extends EventHandler {
/**
* The type of the handler.
*/
Type TYPE = new Type();
/**
*
* Called when a layer becomes visible on the map. It doesn't matter what caused the layer to become visible (marked
* as visible, zoom came into scale range, ...). This method is executed at the moment a layer has become visible.
*
*
* If this method is called, then the method layer.isShowing() must return TRUE.
*
*
* @param event
* The event that indicates which layer specifically became visible.
*/
void onShow(LayerShowEvent event);
/**
*
* Called when a layer becomes invisible on the map. It doesn't matter what caused the layer to become invisible
* (marked as invisible, zoom out of the scale range, ...). This method is executed when a layer becomes invisible.
*
*
* If this method is called, then the method layer.isShowing() must return FALSE.
*
*
* @param event
* The event that indicates which layer specifically became invisible.
*/
void onHide(LayerHideEvent event);
/**
*
* Called when a layer has been marked as visible/invisible. When a layer has been marked as invisible, expect a
* call to onHide very soon.
*
*
* But, when a layer has been marked as visible, that does not necessarily mean it will become visible. There are
* more requirements that have to be met in order for a layer to become visible: the map's scale must be between the
* minimum and maximum allowed scales for the layer. If that requirement has been met as well, expect a call to
* onShow shortly.
*
*
* @param event
* The event that indicates which layer has been marked as visible or invisible (you can ask the layer
* itself).
*/
void onVisibilityMarked(LayerVisibilityMarkedEvent event);
}