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1、什么是Open Core?
Open Core 是 Android 多媒体框架的核心，所有 Android 平台的音频、视频的采用以及播放等操作，都是通过它来实现。
2、Open Core 的具体功能
Open Core 是一个多媒体的框架，从宏观上来看，它主要包含了两大方面的内容：
3、Mediaplayer 介绍
MediaPlayer 类可以用来播放音频、视频和流媒体，MediaPlayer 包含了 Audio 和 Video 的播放功能，在 Android 的界面上， Music 和 Video 两个应用程序都是调用 MediaPlayer 实现的。下面两张图是 MediaPlayer 在 Android 和 Open Core 的示例图：
下面是图例显示 MediaPlayer 的生命周期
3.1、MediaPlayer 常用方法介绍
4、完整音乐播放例子演示
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
界面：
main.xml：
<pre name="code" class="html"><span style="font-size:14px;"><?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></span> item.xml：
<span style="font-size:14px;"><?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></span><span style="font-size: 18px;"> </span>
MainActivity:<pre name="code" class="java"><span style="font-size:14px;">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);
}
private final class MyPhoneStateListener extends PhoneStateListener {
public void onCallStateChanged(int state, String incomingNumber) {
pause();
}
}
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();
}
}
public void next(View view) {
next();
}
public void previous(View view) {
previous();
}
private void previous() {
current = current - 1 < 0 ? data.size() - 1 : current - 1;
play();
}
private void next() {
current = (current + 1) % data.size();
play();
}
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;
}
}
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();
}
}
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
}
}
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("||");
}
}
private void resume() {
if (isPause) {
player.start();
isPause = false;
}
}
private void pause() {
if (player != null && player.isPlaying()) {
player.pause();
isPause = true;
}
}
private final class PhoneListener extends BroadcastReceiver {
public void onReceive(Context context, Intent intent) {
pause();
}
}
protected void onResume() {
super.onResume();
resume();
}
}
</span>注册权限：
<pre name="code" class="html"><?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>
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原文地址：http://blog.csdn.net/chaoyu168/article/details/51150983
