/* * Copyright 2000-2013 Vaadin Ltd. * * 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.vaadin.ui; /** * Interface implemented by {@link HasComponents} implementors that wish to * dynamically be able to prevent given child components from reaching the * client side. * * @author Vaadin Ltd * @version @VERSION@ * @since 7.0 * */ public interface SelectiveRenderer extends HasComponents { /** * Checks if the child component should be rendered (sent to the client * side). This method allows hiding a child component from updates and * communication to and from the client. It is mostly useful for parents * which show only a limited number of their children at any given time and * want to allow updates only for the visible children (e.g. TabSheet has * one tab open at a time). *

* This method can only prevent updates from reaching the client, not force * child components to reach the client. If the child is set to visible, * returning false will prevent the child from being sent to the client. If * a child is set to invisible, this method has no effect. *

* * @param childComponent * The child component to check * @return true if the child component may be sent to the client, false * otherwise */ public boolean isRendered(Component childComponent); }