| /* |
| * 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.user.cellview.client; |
| |
| import com.google.gwt.event.shared.EventHandler; |
| import com.google.gwt.event.shared.GwtEvent; |
| |
| /** |
| * An event used to indicate that the data loading state has changed. |
| */ |
| public class LoadingStateChangeEvent extends |
| GwtEvent<LoadingStateChangeEvent.Handler> { |
| |
| /** |
| * Implemented by handlers of {@link LoadingStateChangeEvent}. |
| */ |
| public interface Handler extends EventHandler { |
| /** |
| * Called when a {@link LoadingStateChangeEvent} is fired. |
| * |
| * @param event the {@link LoadingStateChangeEvent} |
| */ |
| void onLoadingStateChanged(LoadingStateChangeEvent event); |
| } |
| |
| /** |
| * Represents the current status of the data being loaded. |
| */ |
| public static interface LoadingState { |
| /** |
| * Indicates that the data has started to load. |
| */ |
| LoadingState LOADING = new DefaultLoadingState(); |
| |
| /** |
| * Indicates that part of the data set has been loaded, but more data is |
| * still pending. |
| */ |
| LoadingState PARTIALLY_LOADED = new DefaultLoadingState(); |
| |
| /** |
| * Indicates that the data set has been completely loaded. |
| */ |
| LoadingState LOADED = new DefaultLoadingState(); |
| } |
| |
| /** |
| * Default implementation of {@link LoadingState}. |
| */ |
| private static class DefaultLoadingState implements LoadingState { |
| } |
| |
| /** |
| * A singleton instance of Type. |
| */ |
| public static final Type<Handler> TYPE = new Type<Handler>(); |
| |
| private final LoadingState state; |
| |
| /** |
| * Construct a new {@link LoadingStateChangeEvent}. |
| * |
| * @param state the new state |
| */ |
| public LoadingStateChangeEvent(LoadingState state) { |
| this.state = state; |
| } |
| |
| @Override |
| public Type<Handler> getAssociatedType() { |
| return TYPE; |
| } |
| |
| /** |
| * Get the new {@link LoadingState} associated with this event. |
| * |
| * @return the {@link LoadingState} |
| */ |
| public LoadingState getLoadingState() { |
| return state; |
| } |
| |
| @Override |
| protected void dispatch(Handler handler) { |
| handler.onLoadingStateChanged(this); |
| } |
| } |