/*
* Copyright (c) 2011 PonySDK
* Owners:
* Luciano Broussal <luciano.broussal AT gmail.com>
* Mathieu Barbier <mathieu.barbier AT gmail.com>
* Nicolas Ciaravola <nicolas.ciaravola.pro AT gmail.com>
*
* WebSite:
* http://code.google.com/p/pony-sdk/
*
* 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.ponysdk.ui.server.basic;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
import com.ponysdk.core.instruction.History;
import com.ponysdk.core.stm.Txn;
import com.ponysdk.ui.server.basic.event.PValueChangeEvent;
import com.ponysdk.ui.server.basic.event.PValueChangeHandler;
import com.ponysdk.ui.terminal.Dictionnary.HISTORY;
/**
* This class allows you to interact with the browser's history stack. Each "item" on the stack is represented
* by a single string, referred to as a "token". You can create new history items (which have a token
* associated with them when they are created), and you can programmatically force the current history to move
* back or forward.
* <p>
* In order to receive notification of user-directed changes to the current history item, implement the
* {@link PValueChangeHandler} interface and attach it via {@link #addValueChangeHandler(PValueChangeHandler)}
* .
* </p>
* <p>
* <h3>URL Encoding</h3> Any valid characters may be used in the history token and will survive round-trips
* through {@link #newItem(String)} to {@link #getToken()}/
* {@link PValueChangeHandler#onValueChange(PValueChangeEvent)} , but most will be encoded in the user-visible
* URL. The following US-ASCII characters are not encoded on any currently supported browser (but may be in
* the future due to future browser changes):
* <ul>
* <li>a-z
* <li>A-Z
* <li>0-9
* <li>;,/?:@&=+$-_.!~*()
* </ul>
* </p>
*/
public class PHistory {
private final List<PValueChangeHandler<String>> handlers = new CopyOnWriteArrayList<PValueChangeHandler<String>>();
private String token;
public void addValueChangeHandler(final PValueChangeHandler<String> handler) {
handlers.add(handler);
}
public void newItem(final String token) {
newItem(token, true);
}
public void newItem(final String token, final boolean fireEvents) {
this.token = token;
final History history = new History(token);
history.put(HISTORY.FIRE_EVENTS, fireEvents);
Txn.get().getTxnContext().save(history);
}
public void fireHistoryChanged(final String token) {
this.token = token;
final PValueChangeEvent<String> event = new PValueChangeEvent<String>(this, token);
for (final PValueChangeHandler<String> handler : handlers) {
handler.onValueChange(event);
}
}
public String getToken() {
return token;
}
}