/MusicLockTutorial/src/com/marvin/rocklock/DirectoryStructuredSongPicker.java

  1/*
  2 * Copyright (C) 2010 Google Inc.
  3 * 
  4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
  5 * use this file except in compliance with the License. You may obtain a copy of
  6 * the License at
  7 * 
  8 * http://www.apache.org/licenses/LICENSE-2.0
  9 * 
 10 * Unless required by applicable law or agreed to in writing, software
 11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 13 * License for the specific language governing permissions and limitations under
 14 * the License.
 15 */
 16
 17package com.marvin.rocklock;
 18
 19import android.app.Activity;
 20import android.content.SharedPreferences;
 21import android.content.SharedPreferences.Editor;
 22import android.os.Environment;
 23import android.preference.PreferenceManager;
 24
 25import java.io.File;
 26import java.io.FileFilter;
 27
 28/**
 29 * SongPicker implementation that uses the directory structure to organize the
 30 * music instead of using the tags in the music files. For music to be picked
 31 * up, it has to be put in the /sdcard/RockLock/.music directory.
 32 * 
 33 * @author clchen@google.com (Charles L. Chen)
 34 */
 35public class DirectoryStructuredSongPicker implements SongPicker {
 36    private static final String PREF_ARTIST = "DIR_ARTIST";
 37
 38    private static final String PREF_ALBUM = "DIR_ALBUM";
 39
 40    private static final String PREF_TRACK = "DIR_TRACK";
 41
 42    private static final File musicDir = new File(Environment.getExternalStorageDirectory() + "/RockLock/.music");
 43
 44    private class DirectoryFilter implements FileFilter {
 45        @Override
 46        public boolean accept(File pathname) {
 47            if (pathname.isDirectory()) {
 48                return true;
 49            }
 50            return false;
 51        }
 52    }
 53
 54    private class MP3Filter implements FileFilter {
 55        @Override
 56        public boolean accept(File pathname) {
 57            if (pathname.isFile() && pathname.toString().endsWith(".mp3")) {
 58                return true;
 59            }
 60            return false;
 61        }
 62    }
 63
 64    private Editor editor;
 65
 66    private String currentArtistFullPath;
 67
 68    private String currentAlbumFullPath;
 69
 70    private String currentTrackFullPath;
 71
 72    public DirectoryStructuredSongPicker(Activity parentActivity) {
 73        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(parentActivity);
 74        editor = prefs.edit();
 75        if (!musicDir.exists()) {
 76            musicDir.mkdirs();
 77        }
 78        if (!restoreFromPrefs(prefs)) {
 79            currentArtistFullPath = "";
 80            currentAlbumFullPath = "";
 81            currentTrackFullPath = "";
 82            goNextArtist();
 83        }
 84    }
 85
 86    private boolean restoreFromPrefs(SharedPreferences prefs) {
 87        currentArtistFullPath = prefs.getString(PREF_ARTIST, "");
 88        currentAlbumFullPath = prefs.getString(PREF_ALBUM, "");
 89        currentTrackFullPath = prefs.getString(PREF_TRACK, "");
 90        if (new File(currentArtistFullPath).exists() && new File(currentAlbumFullPath).exists()
 91                && new File(currentTrackFullPath).exists()) {
 92            return true;
 93        }
 94        return false;
 95    }
 96
 97    private String filePathToName(final String filePath) {
 98        String name = filePath;
 99        int startIndex = name.lastIndexOf("/") + 1;
100        int endIndex = name.lastIndexOf(".");
101        if (endIndex > startIndex) {
102            return name.substring(startIndex, endIndex);
103        } else {
104            return name.substring(startIndex);
105        }
106    }
107
108    public String peekNextArtist() {
109        String artist = "";
110        File[] artists = musicDir.listFiles(new DirectoryFilter());
111        if ((artists == null) || (artists.length == 0)) {
112            return "";
113        }
114        java.util.Arrays.sort(artists);
115        if (currentArtistFullPath.length() > 1) {
116            boolean moved = false;
117            for (int i = 0; i < artists.length - 1; i++) {
118                if (currentArtistFullPath.equals(artists[i].getAbsolutePath())) {
119                    return filePathToName(artists[i + 1].getAbsolutePath());
120                }
121            }
122        }
123        return filePathToName(artists[0].getAbsolutePath());
124    }
125
126    public String peekPrevArtist() {
127        String artist = "";
128        File[] artists = musicDir.listFiles(new DirectoryFilter());
129        if ((artists == null) || (artists.length == 0)) {
130            return "";
131        }
132        java.util.Arrays.sort(artists);
133        if (currentArtistFullPath.length() > 1) {
134            boolean moved = false;
135            for (int i = artists.length - 1; i > 0; i--) {
136                if (currentArtistFullPath.equals(artists[i].getAbsolutePath())) {
137                    return filePathToName(artists[i - 1].getAbsolutePath());
138                }
139            }
140        }
141        return filePathToName(artists[artists.length - 1].getAbsolutePath());
142    }
143
144    public String goNextArtist() {
145        currentArtistFullPath = musicDir + "/" + peekNextArtist();
146        currentAlbumFullPath = "";
147        goNextAlbum();
148        currentTrackFullPath = "";
149        goNextTrack();
150        return filePathToName(currentArtistFullPath);
151    }
152
153    public String goPrevArtist() {
154        currentArtistFullPath = musicDir + "/" + peekPrevArtist();
155        currentAlbumFullPath = "";
156        goNextAlbum();
157        currentTrackFullPath = "";
158        goNextTrack();
159        return filePathToName(currentArtistFullPath);
160    }
161
162    public String peekNextAlbum() {
163        File artistDir = new File(currentArtistFullPath);
164        File[] albums = artistDir.listFiles(new DirectoryFilter());
165        if ((albums == null) || (albums.length == 0)) {
166            return "";
167        }
168        java.util.Arrays.sort(albums);
169        if (currentAlbumFullPath.length() > 1) {
170            boolean moved = false;
171            for (int i = 0; i < albums.length - 1; i++) {
172                if (currentAlbumFullPath.equals(albums[i].getAbsolutePath())) {
173                    return filePathToName(albums[i + 1].getAbsolutePath());
174                }
175            }
176        }
177        return filePathToName(albums[0].getAbsolutePath());
178    }
179
180    public String goNextAlbum() {
181        currentAlbumFullPath = currentArtistFullPath + "/" + peekNextAlbum();
182        currentTrackFullPath = "";
183        goNextTrack();
184        return filePathToName(currentAlbumFullPath);
185    }
186
187    public String peekPrevAlbum() {
188        File artistDir = new File(currentArtistFullPath);
189        File[] albums = artistDir.listFiles(new DirectoryFilter());
190        if ((albums == null) || (albums.length == 0)) {
191            return "";
192        }
193        java.util.Arrays.sort(albums);
194        if (currentAlbumFullPath.length() > 1) {
195            boolean moved = false;
196            for (int i = albums.length - 1; i > 0; i--) {
197                if (currentAlbumFullPath.equals(albums[i].getAbsolutePath())) {
198                    return filePathToName(albums[i - 1].getAbsolutePath());
199                }
200            }
201        }
202        return filePathToName(albums[albums.length - 1].getAbsolutePath());
203    }
204
205    public String goPrevAlbum() {
206        currentAlbumFullPath = currentArtistFullPath + "/" + peekPrevAlbum();
207        currentTrackFullPath = "";
208        goNextTrack();
209        return filePathToName(currentAlbumFullPath);
210    }
211
212    public String peekNextTrack() {
213        File trackDir = new File(currentAlbumFullPath);
214        File[] tracks = trackDir.listFiles(new MP3Filter());
215        if ((tracks == null) || (tracks.length == 0)) {
216            return "";
217        }
218        java.util.Arrays.sort(tracks);
219        if (currentTrackFullPath.length() > 1) {
220            boolean moved = false;
221            for (int i = 0; i < tracks.length - 1; i++) {
222                if (currentTrackFullPath.equals(tracks[i].getAbsolutePath())) {
223                    return filePathToName(tracks[i + 1].getAbsolutePath());
224                }
225            }
226        }
227        return filePathToName(tracks[0].getAbsolutePath());
228    }
229
230    public String goNextTrack() {
231        currentTrackFullPath = currentAlbumFullPath + "/" + peekNextTrack() + ".mp3";
232        return filePathToName(currentTrackFullPath);
233    }
234
235    public String peekPrevTrack() {
236        File trackDir = new File(currentAlbumFullPath);
237        File[] tracks = trackDir.listFiles(new MP3Filter());
238        if ((tracks == null) || (tracks.length == 0)) {
239            return "";
240        }
241        java.util.Arrays.sort(tracks);
242        if (currentTrackFullPath.length() > 1) {
243            boolean moved = false;
244            for (int i = tracks.length - 1; i > 0; i--) {
245                if (currentTrackFullPath.equals(tracks[i].getAbsolutePath())) {
246                    return filePathToName(tracks[i - 1].getAbsolutePath());
247                }
248            }
249        }
250        return filePathToName(tracks[tracks.length - 1].getAbsolutePath());
251    }
252
253    public String goPrevTrack() {
254        currentTrackFullPath = currentAlbumFullPath + "/" + peekPrevTrack() + ".mp3";
255        return filePathToName(currentTrackFullPath);
256    }
257
258    public String getCurrentSongFile() {
259        editor.putString(PREF_ARTIST, currentArtistFullPath);
260        editor.putString(PREF_ALBUM, currentAlbumFullPath);
261        editor.putString(PREF_TRACK, currentTrackFullPath);
262        editor.commit();
263        return currentTrackFullPath;
264    }
265
266    public String getCurrentSongInfo() {
267        return filePathToName(currentArtistFullPath) + "\n" + filePathToName(currentAlbumFullPath)
268                + "\n" + filePathToName(currentTrackFullPath);
269    }
270}