Android開發音樂播放器

音樂播放器中綜合了以下內容：

SeekBar、ListView、廣播接收者(以代碼的形式注冊Receiver)、系統服務、MediaPlayer

實現的功能：

1.暫停/播放、下一首/上一首，點擊某一首時播放

2.支持拖動進度條快進

3.列表排序

4.來電話時，停止播放，掛斷後繼續播放

5.可在後台播放

效果圖：

界面：

main.xml：

1. <?xml version="1.0" encoding="utf-8"?>
2. <LinearLayout xmlns:Android="http://schemas.android.com/apk/res/android"
3. android:orientation="vertical"
4. android:layout_width="fill_parent"
5. android:layout_height="fill_parent"
6. >
7. <TextView
8. android:id="@+id/name"
9. android:layout_width="fill_parent"
10. android:layout_height="wrap_content"
11. />
12. <SeekBar
13. android:id="@+id/seekBar"
14. android:layout_width="fill_parent"
15. android:layout_height="wrap_content"
16. android:layout_marginBottom="5dp"
17. />
18. <LinearLayout
19. android:layout_width="fill_parent"
20. android:layout_height="wrap_content"
21. android:layout_marginBottom="20dp"
22. >
23. <Button
24. android:layout_width="40dp"
25. android:layout_height="40dp"
26. android:text="|◀"
27. android:onClick="previous"
28. />
29. <Button
30. android:id="@+id/pp"
31. android:layout_width="40dp"
32. android:layout_height="40dp"
33. android:text="▶"
34. android:onClick="pp"
35. />
36. <Button
37. android:layout_width="40dp"
38. android:layout_height="40dp"
39. android:text="▶|"
40. android:onClick="next"
41. />
42. </LinearLayout>
43. <ListView
44. android:id="@+id/list"
45. android:layout_width="fill_parent"
46. android:layout_height="fill_parent"
47. />
48. </LinearLayout>

item.xml：

1. <?xml version="1.0" encoding="utf-8"?>
2. <LinearLayout
3. xmlns:android="http://schemas.android.com/apk/res/android"
4. android:layout_width="fill_parent"
5. android:layout_height="wrap_content"
6. android:padding="10dp"
7. >
8. <TextView
9. android:id="@+id/mName"
10. android:layout_width="fill_parent"
11. android:layout_height="wrap_content"
12. android:textSize="15sp"
13. />
14. </LinearLayout>

MainActivity:

1. package cn.test.audio;
3. import java.io.File;
4. import java.util.ArrayList;
5. import java.util.Collections;
6. import java.util.HashMap;
7. import java.util.List;
8. import java.util.Map;
10. import android.app.Activity;
11. import android.content.BroadcastReceiver;
12. import android.content.Context;
13. import android.content.Intent;
14. import android.content.IntentFilter;
15. import android.media.MediaPlayer;
16. import android.media.MediaPlayer.OnCompletionListener;
17. import android.os.Bundle;
18. import android.os.Environment;
19. import android.os.Handler;
20. import android.telephony.PhoneStateListener;
21. import android.telephony.TelephonyManager;
22. import android.view.View;
23. import android.widget.AdapterView;
24. import android.widget.Button;
25. import android.widget.ListView;
26. import android.widget.SeekBar;
27. import android.widget.SimpleAdapter;
28. import android.widget.TextView;
29. import android.widget.AdapterView.OnItemClickListener;
30. import android.widget.SeekBar.OnSeekBarChangeListener;
32. public class MainActivity extends Activity {
33. private TextView nameTextView;
34. private SeekBar seekBar;
35. private ListView listView;
36. private List<Map<String, String>> data;
37. private int current;
38. private MediaPlayer player;
39. private Handler handler = new Handler();
40. private Button ppButton;
41. private boolean isPause;
42. private boolean isStartTrackingTouch;
44. public void onCreate(Bundle savedInstanceState) {
45. super.onCreate(savedInstanceState);
46. setContentView(R.layout.main);
48. nameTextView = (TextView) findViewById(R.id.name);
49. seekBar = (SeekBar) findViewById(R.id.seekBar);
50. listView = (ListView) findViewById(R.id.list);
51. ppButton = (Button) findViewById(R.id.pp);
53. //創建一個音樂播放器
54. player = new MediaPlayer();
56. //顯示音樂播放列表
57. generateListView();
59. //進度條監聽器
60. seekBar.setOnSeekBarChangeListener(new MySeekBarListener());
62. //播放器監聽器
63. player.setOnCompletionListener(new MyPlayerListener());
65. //意圖過濾器
66. IntentFilter filter = new IntentFilter();
68. //播出電話暫停音樂播放
69. filter.addAction("android.intent.action.NEW_OUTGOING_CALL");
70. registerReceiver(new PhoneListener(), filter);
72. //創建一個電話服務
73. TelephonyManager manager = (TelephonyManager) getSystemService(TELEPHONY_SERVICE);
75. //監聽電話狀態，接電話時停止播放
76. manager.listen(new MyPhoneStateListener(), PhoneStateListener.LISTEN_CALL_STATE);
77. }
79. /*
80. * 監聽電話狀態
81. */
82. private final class MyPhoneStateListener extends PhoneStateListener {
83. public void onCallStateChanged(int state, String incomingNumber) {
84. pause();
85. }
86. }
88. /*
89. * 播放器監聽器
90. */
91. private final class MyPlayerListener implements OnCompletionListener {
92. //歌曲播放完後自動播放下一首歌曲
93. public void onCompletion(MediaPlayer mp) {
94. next();
95. }
96. }
98. /*
99. * 下一首按鈕
100. */
101. public void next(View view) {
102. next();
103. }
105. /*
106. * 前一首按鈕
107. */
108. public void previous(View view) {
109. previous();
110. }
112. /*
113. * 播放前一首歌
114. */
115. private void previous() {
116. current = current - 1 < 0 ? data.size() - 1 : current - 1;
117. play();
118. }
120. /*
121. * 播放下一首歌
122. */
123. private void next() {
124. current = (current + 1) % data.size();
125. play();
126. }
128. /*
129. * 進度條監聽器
130. */
131. private final class MySeekBarListener implements OnSeekBarChangeListener {
132. //移動觸發
133. public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
134. }
136. //起始觸發
137. public void onStartTrackingTouch(SeekBar seekBar) {
138. isStartTrackingTouch = true;
139. }
141. //結束觸發
142. public void onStopTrackingTouch(SeekBar seekBar) {
143. player.seekTo(seekBar.getProgress());
144. isStartTrackingTouch = false;
145. }
146. }
148. /*
149. * 顯示音樂播放列表
150. */
151. private void generateListView() {
152. List<File> list = new ArrayList<File>();
154. //獲取sdcard中的所有歌曲
155. findAll(Environment.getExternalStorageDirectory(), list);
157. //播放列表進行排序，字符順序
158. Collections.sort(list);
160. data = new ArrayList<Map<String, String>>();
161. for (File file : list) {
162. Map<String, String> map = new HashMap<String, String>();
163. map.put("name", file.getName());
164. map.put("path", file.getAbsolutePath());
165. data.add(map);
166. }
168. SimpleAdapter adapter = new SimpleAdapter(this, data, R.layout.item, new String[] { "name" }, new int[] { R.id.mName });
169. listView.setAdapter(adapter);
171. listView.setOnItemClickListener(new MyItemListener());
172. }
174. private final class MyItemListener implements OnItemClickListener {
175. public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
176. current = position;
177. play();
178. }
179. }
182. private void play() {
183. try {
184. //重播
185. player.reset();
187. //獲取歌曲路徑
188. player.setDataSource(data.get(current).get("path"));
190. //緩沖
191. player.prepare();
193. //開始播放
194. player.start();
196. //顯示歌名
197. nameTextView.setText(data.get(current).get("name"));
199. //設置進度條長度
200. seekBar.setMax(player.getDuration());
202. //播放按鈕樣式
203. ppButton.setText("||");
205. //發送一個Runnable, handler收到之後就會執行run()方法
206. handler.post(new Runnable() {
207. public void run() {
208. // 更新進度條狀態
209. if (!isStartTrackingTouch)
210. seekBar.setProgress(player.getCurrentPosition());
211. // 1秒之後再次發送
212. handler.postDelayed(this, 1000);
213. }
214. });
215. } catch (Exception e) {
216. e.printStackTrace();
217. }
218. }
220. /**
221. * 查找文件路徑中所有mp3文件
222. * @param file 要找的目錄
223. * @param list 用來裝文件的List
224. */
225. private void findAll(File file, List<File> list) {
226. File[] subFiles = file.listFiles();
227. if (subFiles != null)
228. for (File subFile : subFiles) {
229. if (subFile.isFile() && subFile.getName().endsWith(".mp3"))
230. list.add(subFile);
231. else if (subFile.isDirectory())//如果是目錄
232. findAll(subFile, list); //遞歸
233. }
234. }
236. /*
237. * 暫停/播放按鈕
238. */
239. public void pp(View view) {
241. //默認從第一首歌曲開始播放
242. if (!player.isPlaying() && !isPause) {
243. play();
244. return;
245. }
247. Button button = (Button) view;
248. //暫停/播放按鈕
249. if ("||".equals(button.getText())) {
250. pause();
251. button.setText("▶");
252. } else {
253. resume();
254. button.setText("||");
255. }
256. }
258. /*
259. * 開始操作
260. */
261. private void resume() {
262. if (isPause) {
263. player.start();
264. isPause = false;
265. }
266. }
268. /*
269. * 暫停操作
270. */
271. private void pause() {
272. if (player != null && player.isPlaying()) {
273. player.pause();
274. isPause = true;
275. }
276. }
278. /*
279. * 收到廣播時暫停
280. */
281. private final class PhoneListener extends BroadcastReceiver {
282. public void onReceive(Context context, Intent intent) {
283. pause();
284. }
285. }
287. /*
288. * 恢復播放
289. * @see android.app.Activity#onResume()
290. */
291. protected void onResume() {
292. super.onResume();
293. resume();
294. }
295. }

注冊權限：

1. <?xml version="1.0" encoding="utf-8"?>
2. <manifest xmlns:android="http://schemas.android.com/apk/res/android"
3. package="cn.itcast.audio"
4. android:versionCode="1"
5. android:versionName="1.0">
6. <application android:icon="@drawable/icon" android:label="@string/app_name">
7. <activity android:name=".MainActivity"
8. android:label="@string/app_name">
9. <intent-filter>
10. <action android:name="android.intent.action.MAIN" />
11. <category android:name="android.intent.category.LAUNCHER" />
12. </intent-filter>
13. </activity>
15. </application>
16. <uses-sdk android:minSdkVersion="8" />
18. <!-- 監聽電話呼出 -->
19. <uses-permission android:name="android.permission.PROCESS_OUTGOING_CALLS"/>
20. <!-- 監聽電話狀態改變 -->
21. <uses-permission android:name="android.permission.READ_PHONE_STATE" />
23. </manifest>