【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

<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

<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> itemList;
    private Stack 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 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> getData(String path) {
        List> list = new ArrayList>();

        Map map = new HashMap();
        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 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