Android應用開發之視頻播放器

資源：

ImageButton所用圖片4張

1. <string name="app_name">MyVideoPlayer</string>  
2.     <string name="video_text">視頻文件</string>  
3.     <string name="notfoundsdcard_error">找不到Sd卡</string>  
4.     <string name="notfoundfile_error">找不到視頻文件</string>  

布局

1. <?xml version="1.0" encoding="utf-8"?>  
2. <LinearLayout xmlns:Android="http://schemas.android.com/apk/res/android"  
3.     android:layout_width="fill_parent"  
4.     android:layout_height="fill_parent"  
5.     android:background="#FFFFCC"  
6.     android:orientation="vertical" >  
7.   
8.     <TextView  
9.         android:layout_width="fill_parent"  
10.         android:layout_height="wrap_content"  
11.         android:text="@string/video_text" />  
12.   
13.     <EditText  
14.         android:id="@+id/videoFileEt"  
15.         android:layout_width="fill_parent"  
16.         android:layout_height="wrap_content"  
17.         android:text="cat.3gp" />  
18.   
19.     <TableLayout  
20.         android:layout_width="fill_parent"  
21.         android:layout_height="wrap_content"  
22.         android:gravity="center"  
23.         android:stretchColumns="*" >  
24.   
25.         <TableRow >  
26.   
27.             <ImageButton  
28.                 android:id="@+id/playBtn"  
29.                 android:layout_width="wrap_content"  
30.                 android:layout_height="wrap_content"  
31.                 android:src="@drawable/play" />  
32.   
33.             <ImageButton  
34.                 android:id="@+id/pauseBtn"  
35.                 android:layout_width="wrap_content"  
36.                 android:layout_height="wrap_content"  
37.                 android:src="@drawable/pause" />  
38.   
39.             <ImageButton  
40.                 android:id="@+id/resetBtn"  
41.                 android:layout_width="wrap_content"  
42.                 android:layout_height="wrap_content"  
43.                 android:src="@drawable/reset" />  
44.   
45.             <ImageButton  
46.                 android:id="@+id/stopBtn"  
47.                 android:layout_width="wrap_content"  
48.                 android:layout_height="wrap_content"  
49.                 android:src="@drawable/stop" />  
50.         </TableRow>  
51.     </TableLayout>  
52.   
53.     <SurfaceView  
54.         android:id="@+id/surfaceView"  
55.         android:layout_width="fill_parent"  
56.         android:layout_height="240dip" />  
57.   
58. </LinearLayout>  

Activity

1. package cn.class3g.videoplayer;  
2.   
3. import java.io.File;  
4. import java.io.IOException;  
5.   
6. import android.app.Activity;  
7. import android.media.AudioManager;  
8. import android.media.MediaPlayer;  
9. import android.os.Bundle;  
10. import android.os.Environment;  
11. import android.util.Log;  
12. import android.view.SurfaceHolder;  
13. import android.view.SurfaceHolder.Callback;  
14. import android.view.SurfaceView;  
15. import android.view.View;  
16. import android.view.View.OnClickListener;  
17. import android.widget.EditText;  
18. import android.widget.ImageButton;  
19. import android.widget.Toast;  
20.   
21. public class VideoPlayerActivity extends Activity implements OnClickListener {  
22.   
23.     private static final String TAG = "VideoPlayerActivity";  
24.     private ImageButton playBtn, pauseBtn, resetBtn, stopBtn;  
25.     private EditText fileEt;  
26.     private SurfaceView videoSv;  
27.   
28.     private MediaPlayer mediaPlayer;  
29.   
30.     private SurfaceHolder holder;  
31.     private int position = 0;  
32.     File videoFile = null;  
33.       
34.   
35.     public void onCreate(Bundle savedInstanceState) {  
36.         super.onCreate(savedInstanceState);  
37.         setContentView(R.layout.main);  
38.   
39.         findViews();  
40.   
41.         mediaPlayer = new MediaPlayer();  
42.     }  
43.   
44.     private void findViews() {  
45.         fileEt = (EditText) this.findViewById(R.id.videoFileEt);  
46.         playBtn = (ImageButton) this.findViewById(R.id.playBtn);  
47.         pauseBtn = (ImageButton) this.findViewById(R.id.pauseBtn);  
48.         resetBtn = (ImageButton) this.findViewById(R.id.resetBtn);  
49.         stopBtn = (ImageButton) this.findViewById(R.id.stopBtn);  
50.   
51.         playBtn.setOnClickListener(this);  
52.         pauseBtn.setOnClickListener(this);  
53.         resetBtn.setOnClickListener(this);  
54.         stopBtn.setOnClickListener(this);  
55.   
56.         videoSv = (SurfaceView) this.findViewById(R.id.surfaceView);  
57.         holder = videoSv.getHolder();  
58.   
59.         holder.setFixedSize(176, 144); // 設置分辨率   
60.         /* 下面設置Surface不維護自己的緩沖區，而是等待屏幕的渲染引擎將內容推送到用戶面前 */  
61.         holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);  
62.         //holder.addCallback(new SurfaceCallback());   
63.     }  
64.   
65.     public void onClick(View v) {  
66.   
67.         if (Environment.getExternalStorageState().equals( Environment.MEDIA_MOUNTED)) {  
68.             String fileName = fileEt.getText().toString().trim();  
69.   
70.             videoFile = new File(  
71.                     Environment.getExternalStorageDirectory(), fileName);  
72.             if (videoFile.exists()) {  
73.                 try {  
74.                     switch (v.getId()) {  
75.                     case R.id.playBtn:  
76.                         playVideo(videoFile);  
77.                         break;  
78.                     case R.id.pauseBtn:  
79. //                      if(mediaPlayer.isPlaying()){   
80. //                          mediaPlayer.pause();   
81. //                      }else{   
82. //                          mediaPlayer.start();   
83. //                      }   
84.                         if(mediaPlayer.isPlaying()){  
85.                             position = mediaPlayer.getCurrentPosition();  
86.                             mediaPlayer.pause();  
87.                         }  
88.                           
89.                         break;  
90.                     case R.id.resetBtn:  
91.                         if(mediaPlayer.isPlaying()){  
92.                             mediaPlayer.seekTo(0);  
93.                         }else{  
94.                             playVideo(videoFile);  
95.                         }  
96.                         break;  
97.                     case R.id.stopBtn:  
98.                         if(mediaPlayer.isPlaying()){  
99.                             mediaPlayer.stop();  
100.                         }  
101.                         break;  
102.                     }  
103.                 } catch (Exception e) {  
104.                     Log.e(TAG, e.toString());  
105.                 }  
106.   
107.             } else {  
108.                 showToast(R.string.notfoundfile_error);  
109.             }  
110.         } else {  
111.             showToast(R.string.notfoundsdcard_error);  
112.         }  
113.     }  
114.   
115.     private void playVideo(File videoFile) throws IOException {  
116.         mediaPlayer.reset();  
117.         mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);  
118.         mediaPlayer.setDataSource(videoFile.getAbsolutePath());  
119.         mediaPlayer.setDisplay(holder);  
120.         mediaPlayer.prepare();  
121.         mediaPlayer.start();  
122.     }  
123.   
124.     private void showToast(int resId) {  
125.         Toast.makeText(this, resId, 1).show();  
126.     }  
127. }