Android开发音乐播放器

音乐播放器中综合了以下内容：

SeekBar、ListView、广播接收者(以代码的形式注册Receiver)、系统服务、MediaPlayer

实现的功能：

1.暂停/播放、下一首/上一首，点击某一首时播放

2.支持拖动进度条快进

3.列表排序

4.来电话时，停止播放，挂断后继续播放

5.可在后台播放

效果图：

界面：

main.xml：

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <TextView android:id="@+id/name" android:layout_width="fill_parent" android:layout_height="wrap_content" /> <SeekBar android:id="@+id/seekBar" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_marginBottom="5dp" /> <LinearLayout android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_marginBottom="20dp" > <Button android:layout_width="40dp" android:layout_height="40dp" android:text="|◀" android:onClick="previous" /> <Button android:id="@+id/pp" android:layout_width="40dp" android:layout_height="40dp" android:text="▶" android:onClick="pp" /> <Button android:layout_width="40dp" android:layout_height="40dp" android:text="▶|" android:onClick="next" /> </LinearLayout> <ListView android:id="@+id/list" android:layout_width="fill_parent" android:layout_height="fill_parent" /> </LinearLayout>

item.xml：

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="wrap_content" android:padding="10dp" > <TextView android:id="@+id/mName" android:layout_width="fill_parent" android:layout_height="wrap_content" android:textSize="15sp" /> </LinearLayout>

MainActivity:

package cn.test.audio; import java.io.File; import java.util.ArrayList; import java.util.Collections; import java.util.HashMap; import java.util.List; import java.util.Map; import android.app.Activity; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.media.MediaPlayer; import android.media.MediaPlayer.OnCompletionListener; import android.os.Bundle; import android.os.Environment; import android.os.Handler; import android.telephony.PhoneStateListener; import android.telephony.TelephonyManager; import android.view.View; import android.widget.AdapterView; import android.widget.Button; import android.widget.ListView; import android.widget.SeekBar; import android.widget.SimpleAdapter; import android.widget.TextView; import android.widget.AdapterView.OnItemClickListener; import android.widget.SeekBar.OnSeekBarChangeListener; public class MainActivity extends Activity { private TextView nameTextView; private SeekBar seekBar; private ListView listView; private List<Map<String, String>> data; private int current; private MediaPlayer player; private Handler handler = new Handler(); private Button ppButton; private boolean isPause; private boolean isStartTrackingTouch; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); nameTextView = (TextView) findViewById(R.id.name); seekBar = (SeekBar) findViewById(R.id.seekBar); listView = (ListView) findViewById(R.id.list); ppButton = (Button) findViewById(R.id.pp); //创建一个音乐播放器 player = new MediaPlayer(); //显示音乐播放列表 generateListView(); //进度条监听器 seekBar.setOnSeekBarChangeListener(new MySeekBarListener()); //播放器监听器 player.setOnCompletionListener(new MyPlayerListener()); //意图过滤器 IntentFilter filter = new IntentFilter(); //播出电话暂停音乐播放 filter.addAction("android.intent.action.NEW_OUTGOING_CALL"); registerReceiver(new PhoneListener(), filter); //创建一个电话服务 TelephonyManager manager = (TelephonyManager) getSystemService(TELEPHONY_SERVICE); //监听电话状态，接电话时停止播放 manager.listen(new MyPhoneStateListener(), PhoneStateListener.LISTEN_CALL_STATE); } /* * 监听电话状态 */ private final class MyPhoneStateListener extends PhoneStateListener { public void onCallStateChanged(int state, String incomingNumber) { pause(); } } /* * 播放器监听器 */ private final class MyPlayerListener implements OnCompletionListener { //歌曲播放完后自动播放下一首歌曲 public void onCompletion(MediaPlayer mp) { next(); } } /* * 下一首按钮 */ public void next(View view) { next(); } /* * 前一首按钮 */ public void previous(View view) { previous(); } /* * 播放前一首歌 */ private void previous() { current = current - 1 < 0 ? data.size() - 1 : current - 1; play(); } /* * 播放下一首歌 */ private void next() { current = (current + 1) % data.size(); play(); } /* * 进度条监听器 */ private final class MySeekBarListener implements OnSeekBarChangeListener { //移动触发 public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) { } //起始触发 public void onStartTrackingTouch(SeekBar seekBar) { isStartTrackingTouch = true; } //结束触发 public void onStopTrackingTouch(SeekBar seekBar) { player.seekTo(seekBar.getProgress()); isStartTrackingTouch = false; } } /* * 显示音乐播放列表 */ private void generateListView() { List<File> list = new ArrayList<File>(); //获取sdcard中的所有歌曲 findAll(Environment.getExternalStorageDirectory(), list); //播放列表进行排序，字符顺序 Collections.sort(list); data = new ArrayList<Map<String, String>>(); for (File file : list) { Map<String, String> map = new HashMap<String, String>(); map.put("name", file.getName()); map.put("path", file.getAbsolutePath()); data.add(map); } SimpleAdapter adapter = new SimpleAdapter(this, data, R.layout.item, new String[] { "name" }, new int[] { R.id.mName }); listView.setAdapter(adapter); listView.setOnItemClickListener(new MyItemListener()); } private final class MyItemListener implements OnItemClickListener { public void onItemClick(AdapterView<?> parent, View view, int position, long id) { current = position; play(); } } private void play() { try { //重播 player.reset(); //获取歌曲路径 player.setDataSource(data.get(current).get("path")); //缓冲 player.prepare(); //开始播放 player.start(); //显示歌名 nameTextView.setText(data.get(current).get("name")); //设置进度条长度 seekBar.setMax(player.getDuration()); //播放按钮样式 ppButton.setText("||"); //发送一个Runnable, handler收到之后就会执行run()方法 handler.post(new Runnable() { public void run() { // 更新进度条状态 if (!isStartTrackingTouch) seekBar.setProgress(player.getCurrentPosition()); // 1秒之后再次发送 handler.postDelayed(this, 1000); } }); } catch (Exception e) { e.printStackTrace(); } } /** * 查找文件路径中所有mp3文件 * @param file 要找的目录 * @param list 用来装文件的List */ private void findAll(File file, List<File> list) { File[] subFiles = file.listFiles(); if (subFiles != null) for (File subFile : subFiles) { if (subFile.isFile() && subFile.getName().endsWith(".mp3")) list.add(subFile); else if (subFile.isDirectory())//如果是目录 findAll(subFile, list); //递归 } } /* * 暂停/播放按钮 */ public void pp(View view) { //默认从第一首歌曲开始播放 if (!player.isPlaying() && !isPause) { play(); return; } Button button = (Button) view; //暂停/播放按钮 if ("||".equals(button.getText())) { pause(); button.setText("▶"); } else { resume(); button.setText("||"); } } /* * 开始操作 */ private void resume() { if (isPause) { player.start(); isPause = false; } } /* * 暂停操作 */ private void pause() { if (player != null && player.isPlaying()) { player.pause(); isPause = true; } } /* * 收到广播时暂停 */ private final class PhoneListener extends BroadcastReceiver { public void onReceive(Context context, Intent intent) { pause(); } } /* * 恢复播放 * @see android.app.Activity#onResume() */ protected void onResume() { super.onResume(); resume(); } }

注册权限：

<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="cn.itcast.audio" android:versionCode="1" android:versionName="1.0"> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".MainActivity" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> <uses-sdk android:minSdkVersion="8" /> <!-- 监听电话呼出 --> <uses-permission android:name="android.permission.PROCESS_OUTGOING_CALLS"/> <!-- 监听电话状态改变 --> <uses-permission android:name="android.permission.READ_PHONE_STATE" /> </manifest>