【Android】如何用MediaPlayer实现一个简单的音视频播放器

我们在上一篇文章 如何实现一个简单的文件浏览器的基础上，使用MeidaPlayer实现对音视频文件的播放功能。
主要代码如下：
Manifest文件

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.example.loushuai.simpleplayer">    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />    <application        android:allowBackup="true"        android:icon="@mipmap/ic_launcher"        android:label="@string/app_name"        android:supportsRtl="true"        android:theme="@style/AppTheme">        <activity            android:name=".MainActivity"            android:label="@string/title_simple_palyer">            <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>        <activity android:name=".PlayerActivity"></activity>    </application></manifest>

activity_player.xml

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="com.example.loushuai.simpleplayer.PlayerActivity">    <SurfaceView android:id="@+id/surfaceView1"        android:layout_height="fill_parent" android:layout_width="fill_parent"></SurfaceView></RelativeLayout>

MainActiviry.java

package com.example.loushuai.simpleplayer;import android.app.ListActivity;import android.content.Intent;import android.os.Bundle;import android.os.Environment;import android.util.Log;import android.view.View;import android.widget.ListView;import android.widget.SimpleAdapter;import android.widget.Toast;import java.io.File;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;import java.util.Stack;public class MainActivity extends ListActivity {    public static final String COLUMN_NAME_NAME = "name";    private SimpleAdapter adapter = null;    private List<Map<String, Object>> itemList;    private Stack<String> pathHistory = null;    private String curPath;    String[] from = { COLUMN_NAME_NAME } ;    int[] to = {R.id.myView1};    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        pathHistory = new Stack<String>();        String sDStateString = Environment.getExternalStorageState();        if(sDStateString.equals(Environment.MEDIA_MOUNTED)) {            File SDFile = Environment.getExternalStorageDirectory();            curPath = SDFile.getAbsolutePath() + "/";            itemList = getData(curPath);            adapter = new SimpleAdapter(this, itemList, R.layout.list_item, from, to);            setListAdapter(adapter);        }    }    private List<Map<String, Object>> getData(String path) {        List<Map<String, Object>> list = new ArrayList<Map<String,Object>>();        Map<String, Object> map = new HashMap<String, Object>();        map.put(COLUMN_NAME_NAME, "..");        list.add(map);        File file = new File(path);        if (file.listFiles().length > 0) {            for (File f : file.listFiles()) {                if (fileFilter(f)) {                    map = new HashMap<String, Object>();                    String name = f.getName();                    if (f.isDirectory()) {                        name += "/";                    }                    map.put(COLUMN_NAME_NAME, name);                    list.add(map);                    Log.d("Scan", " path " + path + f.getName());                }            }        }        return list;    }    @Override    protected void onListItemClick(ListView l, View v, int position, long id) {        super.onListItemClick(l, v, position, id);        String path;        if (position > 0) {            pathHistory.push(curPath);            path = curPath + itemList.get(position).get(COLUMN_NAME_NAME);        } else { // uplevel            if (!pathHistory.empty())                path = pathHistory.pop();            else // root                path = curPath;        }        Log.d("List View Click", " position: " + position + " name: " + path);        File file = new File(path);        if (file.isDirectory()) {            updateList(path);            curPath = path;        } else {            Intent intent = new Intent(MainActivity.this, PlayerActivity.class);            intent.putExtra("path", path);            startActivity(intent);        }    }    private void updateList(String path) {        itemList.clear();        itemList = getData(path);        adapter = new SimpleAdapter(this, itemList, R.layout.list_item, from, to);        setListAdapter(adapter);        adapter.notifyDataSetChanged();    }    private boolean fileFilter(File file) {        if(file.isDirectory()) {            return true;        } else {            String name = file.getName();            if (name.endsWith(".mp3") || name.endsWith(".mp4"))                return true;            else                return false;        }    }}

PlayerActivity.java

package com.example.loushuai.simpleplayer;import android.app.Activity;import android.content.Intent;import android.content.pm.ActivityInfo;import android.os.Bundle;import android.util.Log;import android.view.SurfaceView;import android.view.Window;import android.view.WindowManager;public class PlayerActivity extends Activity {    private SurfaceView surfaceView;    private Player player;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        requestWindowFeature(Window.FEATURE_NO_TITLE);        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,                WindowManager.LayoutParams.FLAG_FULLSCREEN);        setContentView(R.layout.activity_player);        Intent intent = getIntent();        String path = intent.getStringExtra("path");        Log.d("PlayerActivity", " url:" + path);        surfaceView = (SurfaceView) this.findViewById(R.id.surfaceView1);        player = new Player(surfaceView, path);    }    @Override    protected void onResume() {        if(getRequestedOrientation()!= ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE){            setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);        }        super.onResume();    }}

Player.java

package com.example.loushuai.simpleplayer;import android.app.Activity;import android.content.Intent;import android.content.pm.ActivityInfo;import android.os.Bundle;import android.util.Log;import android.view.SurfaceView;import android.view.Window;import android.view.WindowManager;public class PlayerActivity extends Activity {    private SurfaceView surfaceView;    private Player player;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        requestWindowFeature(Window.FEATURE_NO_TITLE);        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,                WindowManager.LayoutParams.FLAG_FULLSCREEN);        setContentView(R.layout.activity_player);        Intent intent = getIntent();        String path = intent.getStringExtra("path");        Log.d("PlayerActivity", " url:" + path);        surfaceView = (SurfaceView) this.findViewById(R.id.surfaceView1);        player = new Player(surfaceView, path);    }    @Override    protected void onResume() {        if(getRequestedOrientation()!= ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE){            setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);        }        super.onResume();    }}

参考文献：
http://blog.csdn.net/hellogv/article/details/6429455