| /* |
| * Copyright 2011 Google Inc. |
| * |
| * 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.google.gwt.sample.ui.client; |
| |
| import com.google.gwt.user.client.ui.IsWidget; |
| import com.google.web.bindery.event.shared.EventBus; |
| |
| /** |
| * Implemented by specialized widget drivers that can answer |
| * {@link com.google.gwt.activity.shared.Activity#mayStop() mayStop()} calls for |
| * {@link com.google.gwt.activity.shared.Activity Activities}. |
| * <p> |
| * Note that this interface extends {@link IsWidget}. This is to make it easier |
| * to evolve app code in MVP directions piecemeal, just where it is useful. If |
| * code that assembles widgets thinks of them strictly as IsWidget instances, it |
| * doesn't need to notice as they get refactored in to Presenter / View pairs. |
| * Or as they don't. |
| */ |
| public interface PresentsWidgets extends IsWidget { |
| /** |
| * Called (probably from |
| * {@link com.google.gwt.activity.shared.Activity#mayStop Activity.mayStop}) |
| * to see if it's safe to stop this presenter. |
| * |
| * @return null if it's okay to stop, else a message to ask the user if she's |
| * sure |
| */ |
| String mayStop(); |
| |
| void start(EventBus eventBus); |
| |
| void stop(); |
| } |