001// Licensed under the Apache License, Version 2.0 (the "License");
002// you may not use this file except in compliance with the License.
003// You may obtain a copy of the License at
004//
005//     http://www.apache.org/licenses/LICENSE-2.0
006//
007// Unless required by applicable law or agreed to in writing, software
008// distributed under the License is distributed on an "AS IS" BASIS,
009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
010// See the License for the specific language governing permissions and
011// limitations under the License.
012
013package org.apache.tapestry5.annotations;
014
015import org.apache.tapestry5.ioc.annotations.UseWith;
016
017import java.lang.annotation.Documented;
018import java.lang.annotation.Retention;
019import java.lang.annotation.Target;
020
021import static java.lang.annotation.ElementType.FIELD;
022import static java.lang.annotation.RetentionPolicy.RUNTIME;
023import static org.apache.tapestry5.ioc.annotations.AnnotationUseContext.PAGE;
024
025/**
026 * Annotation for a field for which the page activation context handlers (onActivate and onPassivate) should be created.
027 * In order to use this annotation you must contribute a {@link org.apache.tapestry5.ValueEncoder} for the class of the
028 * annotated property.
029 *
030 * If using this annotation more than once per page class you must specify unique indexes for each. Indexes must start
031 * at 0 and increment by 1 (eg. if 3 annotations are present they must have indexes of 0, 1 and 2)
032 */
033@Target(FIELD)
034@Documented
035@Retention(RUNTIME)
036@UseWith(PAGE)
037public @interface PageActivationContext
038{
039    /**
040     * Whether to create an activate event handler.
041     */
042    boolean activate() default true;
043
044    /**
045     * Whether to create a passivate event handler
046     */
047    boolean passivate() default true;
048    
049    /**
050     * The index of the page activation context parameter (default 0)
051     * @since 5.4
052     */
053    int index() default 0;
054}