// Copyright 2011, 2012 The Apache Software Foundation
//
// 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.apache.tapestry5.corelib.mixins;
import org.apache.tapestry5.BindingConstants;
import org.apache.tapestry5.ComponentResources;
import org.apache.tapestry5.EventConstants;
import org.apache.tapestry5.EventContext;
import org.apache.tapestry5.Link;
import org.apache.tapestry5.annotations.AfterRender;
import org.apache.tapestry5.annotations.Events;
import org.apache.tapestry5.annotations.InjectContainer;
import org.apache.tapestry5.annotations.Parameter;
import org.apache.tapestry5.corelib.components.Zone;
import org.apache.tapestry5.internal.util.CaptureResultCallback;
import org.apache.tapestry5.ioc.annotations.Inject;
import org.apache.tapestry5.services.javascript.JavaScriptSupport;
/**
* <p>
* This mixin periodically refreshs a {@link org.apache.tapestry5.corelib.components.Zone zone}
* by triggering an event on the server using ajax requests.
* </p>
* <p>
* Server-side, the mixin triggers the "refresh" event with the mixin's context. A container may but
* does not need to handle the event. If the event is handled and a value is returned, that value is
* used to render the response. Otherwise, the Zone's body is re-rendered.
* </p>
* <b>Note: </b> This mixin is only meant for a {@link org.apache.tapestry5.corelib.components.Zone zone}.
*
* @tapestrydoc
*/
@Events(EventConstants.REFRESH)
public class ZoneRefresh
{
/**
* Period between two consecutive refreshes (in seconds). If a new refresh occurs before the
* previous refresh has completed, it will be skipped.
*/
@Parameter(required = true, defaultPrefix = BindingConstants.LITERAL)
private int period;
/**
* Context passed to the event
*/
@Parameter
private Object[] context;
@InjectContainer
private Zone zone;
@Inject
private JavaScriptSupport javaScriptSupport;
@Inject
private ComponentResources resources;
//For testing purpose
ZoneRefresh(Object[] context, ComponentResources resources, JavaScriptSupport javaScriptSupport, Zone zone)
{
this.context = context;
this.resources = resources;
this.javaScriptSupport = javaScriptSupport;
this.zone = zone;
}
@AfterRender
void addJavaScript()
{
Link link = resources.createEventLink("zoneRefresh", context);
javaScriptSupport.require("t5/core/zone-refresh").with(zone.getClientId(), period, link.toString());
}
Object onZoneRefresh(EventContext eventContext)
{
CaptureResultCallback<Object> callback = new CaptureResultCallback<Object>();
resources.triggerContextEvent(EventConstants.REFRESH, eventContext, callback);
if (callback.getResult() != null)
{
return callback.getResult();
}
return zone.getBody();
}
}