Android用SurfaceView播放本地视屏（音频)文件，androidsurfaceview,我们知道Android中

Android用SurfaceView播放本地视屏（音频)文件，androidsurfaceview,我们知道Android中

我们知道Android中可以使 用VideoView播放视频，而且操作简单、方便。除此之外，我们还可以利用MediaPlayer用来播放视频，不过MediaPlayer主要用于 播放音频，没有提供输出图像的输出界面，就是只能听到声音，看不到画面，这时就想到到了SurfaceView控件，将它与MediaPlayer结合起 来，就能达到了视屏播放效果了，今天就做一个简单的视屏播放功能，把准备好的视屏文件test.3gp放在手机SD卡中，然后用SurfaceView来播放：

先看布局activity_main.xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/LinearLayout1"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:weightSum="1"    android:orientation="vertical" >    <SurfaceView        android:id="@+id/surfaceVIew"        android:layout_width="match_parent"        android:layout_height="match_parent"        android:layout_weight="0.15"        tools:context=".MainActivity" />    <LinearLayout         android:orientation="horizontal"        android:layout_width="match_parent"        android:layout_height="match_parent"        android:layout_weight="0.85">        <Button             android:id="@+id/btn_play"            android:text="开始"            android:layout_width="wrap_content"            android:layout_height="wrap_content"/>        <Button            android:id="@+id/btn_pause"            android:text="暂停"            android:layout_width="wrap_content"            android:layout_height="wrap_content"/>        <Button           android:id="@+id/btn_stop"            android:text="停止"            android:layout_width="wrap_content"            android:layout_height="wrap_content"/>        <Button            android:id="@+id/btn_low"            android:text="调低音量"            android:layout_width="wrap_content"            android:layout_height="wrap_content"/>        <Button            android:id="@+id/btn_hight"            android:text="调高音量"            android:layout_width="wrap_content"            android:layout_height="wrap_content"/>    </LinearLayout></LinearLayout>

接着就是Activity:

public class MainActivity extends Activity implements OnClickListener {         /* 功能按钮 */private Button btn_play, btn_pause, btn_stop, btn_low, btn_height;       /* SurfaceView */private SurfaceView mSurfaceView;/* 播放视频对象 */private MediaPlayer mediaPlayer;/* 系统声音 */private AudioManager audioManager;/* 记录播放位置 */private int position;@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);               /*设置窗口无title*/requestWindowFeature(Window.FEATURE_NO_TITLE);                 /*全屏显示*/this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);setContentView(R.layout.activity_main);findViews();setListeners();mediaPlayer = new MediaPlayer();setSurfaceView();}// 横竖屏切换时的处理@Overrideprotected void onSaveInstanceState(Bundle outState) {if (mediaPlayer != null &amp;&amp; mediaPlayer.isPlaying()) {// 如果在播放的时候切换屏幕则保存当前观看的位置outState.putInt("position", mediaPlayer.getCurrentPosition());}super.onSaveInstanceState(outState);}// 横竖屏切换后的处理@Overrideprotected void onRestoreInstanceState(Bundle savedInstanceState) {if (savedInstanceState.containsKey("position")) {position = savedInstanceState.getInt("position");// 取得切换屏幕时保存的位置}super.onRestoreInstanceState(savedInstanceState);}/* 实例化UI */private void findViews() {btn_play = (Button) findViewById(R.id.btn_play);btn_pause = (Button) findViewById(R.id.btn_pause);btn_stop = (Button) findViewById(R.id.btn_stop);btn_low = (Button) findViewById(R.id.btn_low);btn_height = (Button) findViewById(R.id.btn_hight);mSurfaceView = (SurfaceView) findViewById(R.id.surfaceVIew);audioManager = (AudioManager) getSystemService(AUDIO_SERVICE);}/* 为5个按钮设置监听 */private void setListeners() {btn_play.setOnClickListener(this);btn_pause.setOnClickListener(this);btn_stop.setOnClickListener(this);btn_low.setOnClickListener(this);btn_height.setOnClickListener(this);}/* 播放视频 */private void playMedia() {/* 初始化状态 */mediaPlayer.reset();/* 设置声音流类型 */mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);/* 设置mp3\mp4加载路径 */File file = new File(Environment.getExternalStorageDirectory(), "test.3gp");try {mediaPlayer.setDataSource(file.getAbsolutePath());// 缓冲mediaPlayer.prepare();// 开始播放mediaPlayer.start();// 具体位置Log.i("position", position + "------");mediaPlayer.seekTo(position);// 视频输出到ViewmediaPlayer.setDisplay(mSurfaceView.getHolder());// 重置位置为0position = 0;} catch (IllegalArgumentException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IllegalStateException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}/* 设置surfaceView视图 */private void setSurfaceView() {// creates a "push" surfacemSurfaceView.getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);// 设置事件，回调函数mSurfaceView.getHolder().addCallback(new SurfaceHolder.Callback() {/* SurfaceView创建时 */@Overridepublic void surfaceCreated(SurfaceHolder holder) {if (position > 0) {playMedia();position = 0;}}@Overridepublic void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {// TODO Auto-generated method stub}/* SurfaceView销毁视图 */@Overridepublic void surfaceDestroyed(SurfaceHolder holder) {if (mediaPlayer.isPlaying()) {mediaPlayer.stop();}/* Activity销毁时停止播放，释放资源。不做这个操作，即使退出，还是能听到视频的声音 */mediaPlayer.release();}});}@Overridepublic void onClick(View v) {switch (v.getId()) {case R.id.btn_play:// 播放if (mediaPlayer != null &amp;&amp; mediaPlayer.isPlaying()) {return;} else {playMedia();}break;case R.id.btn_pause:// 暂停if (mediaPlayer != null &amp;&amp; mediaPlayer.isPlaying()) {position = mediaPlayer.getCurrentPosition();mediaPlayer.pause();} else {return;}break;case R.id.btn_stop:// 停止if (mediaPlayer != null &amp;&amp; mediaPlayer.isPlaying()) {mediaPlayer.stop();position = 0;} else {return;}break;case R.id.btn_low:// 调小音量// 获取当前的音乐音量int volume = audioManager.getStreamVolume(AudioManager.STREAM_MUSIC);Log.v("Volume", "volume" + volume);// 音量>0if (volume > 0) {audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC, AudioManager.ADJUST_LOWER, 0);} else {return;}break;case R.id.btn_hight:// 调大音量volume = audioManager.getStreamVolume(AudioManager.STREAM_MUSIC);// 音量<100if (volume < audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC)) {audioManager.adjustStreamVolume(AudioManager.STREAM_MUSIC, AudioManager.ADJUST_RAISE, 0);} else {return;}break;}}}