artisttreecontentprovider.java

eclise rcp 项目,是非常好的学习源码

/*******************************************************************************
 * Copyright (c) 2007 Siemens AG
 * 
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Kai T鰀ter - initial API and implementation
 *******************************************************************************/

package com.siemens.ct.mp3m.ui.views.logical;

import java.util.List;

import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.Viewer;

import com.siemens.ct.mp3m.model.logical.Album;
import com.siemens.ct.mp3m.model.logical.Artist;
import com.siemens.ct.mp3m.model.logical.Artists;
import com.siemens.ct.mp3m.model.logical.Song;
import com.siemens.ct.mp3m.model.physical.MusicFolders;
import com.siemens.ct.mp3m.model.physical.MusicFoldersChangeListener;

/**
 * This class provides the content for the TableTreeViewer in ArtistTableTree
 */
class ArtistTreeContentProvider implements ITreeContentProvider, MusicFoldersChangeListener {
	/**
	 * 
	 */
	private final LogicalView view;
	private final Object[] EMPTY = new Object[] {};

	public ArtistTreeContentProvider(LogicalView view) {
		this.view = view;
		MusicFolders.addChangeListener(this);
	}

	/**
	 * Gets the children for Artist or Album
	 * 
	 * @param parent
	 *            the team or Artist
	 * 
	 * @return Object[]
	 */
	public Object[] getChildren(Object parent) {
		if (parent instanceof Artist) {
			return ((Artist) parent).getAlbums().toArray();
		} else if (parent instanceof Album) {
			return ((Album) parent).getSongs().toArray();
		}

		// Titles have no children
		return EMPTY;
	}

	/**
	 * Gets the parent artist for an Album
	 * 
	 * @param child
	 *            the Album
	 * 
	 * @return Object
	 */
	public Object getParent(Object child) {
		if (child instanceof Song) {
			return ((Song) child).getAlbum();
		} else if (child instanceof Album) {

			return ((Album) child).getArtist();
		}
		return null;
	}

	/**
	 * Gets whether this team or Artist has children
	 * 
	 * @param arg0
	 *            the team or Artist
	 * 
	 * @return boolean
	 */
	public boolean hasChildren(Object arg0) {
		return getChildren(arg0).length > 0;
	}

	/**
	 * Gets the elements for the table
	 * 
	 * @param arg0
	 *            the model
	 * 
	 * @return Object[]
	 */
	public Object[] getElements(Object arg0) {
		// Returns all the teams in the model
		return Artists.getArtists();
	}

	/**
	 * Disposes any resources
	 */
	public void dispose() {
		// We don't create any resources, so we don't dispose any
	}

	/**
	 * Called when the input changes
	 * 
	 * @param arg0
	 *            the parent viewer
	 * @param arg1
	 *            the old input
	 * @param arg2
	 *            the new input
	 */
	public void inputChanged(Viewer arg0, Object arg1, Object arg2) {
		// Nothing to do
	}

	@SuppressWarnings("deprecation")
	public void musicFoldersChanged(List<String> folders) {
		if (this.view.treeViewer != null) {
			/*
			Table table = this.view.ttv.getTableTree().getTable();
			// Expand everything
			this.view.ttv.expandAll();

			// Pack the columns
			for (int i = 0, n = table.getColumnCount(); i < n; i++) {
				table.getColumn(i).pack();
			}
*/
			this.view.treeViewer.refresh();
		}
	}
}