如何掃描出Android系統媒體庫中視頻文件

Android系統啟動時會去掃描系統文件，並將系統支持的視頻文件（mp4,3gp,wmv）掃描到媒體庫（MediaStore）中，下面代碼演示如何獲得這些文件的信息：

1. public static List<VideoInfo> sysVideoList = null;// 視頻信息集合
2. sysVideoList = new ArrayList<VideoInfo>();
3. setVideoList();
5. private void setVideoList() {
6. // MediaStore.Video.Thumbnails.DATA:視頻縮略圖的文件路徑
7. String[] thumbColumns = { MediaStore.Video.Thumbnails.DATA,
8. MediaStore.Video.Thumbnails.VIDEO_ID };
10. // MediaStore.Video.Media.DATA：視頻文件路徑；
11. // MediaStore.Video.Media.DISPLAY_NAME : 視頻文件名，如 testVideo.mp4
12. // MediaStore.Video.Media.TITLE: 視頻標題 : testVideo
13. String[] mediaColumns = { MediaStore.Video.Media._ID,
14. MediaStore.Video.Media.DATA, MediaStore.Video.Media.TITLE,
15. MediaStore.Video.Media.MIME_TYPE,
16. MediaStore.Video.Media.DISPLAY_NAME };
18. cursor = managedQuery(MediaStore.Video.Media.EXTERNAL_CONTENT_URI,
19. mediaColumns, null, null, null);
21. if(cursor==null){
22. Toast.makeText(SystemVideoChooseActivity.this, "沒有找到可播放視頻文件", 1).show();
23. return;
24. }
25. if (cursor.moveToFirst()) {
26. do {
27. VideoInfo info = new VideoInfo();
28. int id = cursor.getInt(cursor
29. .getColumnIndex(MediaStore.Video.Media._ID));
30. Cursor thumbCursor = managedQuery(
31. MediaStore.Video.Thumbnails.EXTERNAL_CONTENT_URI,
32. thumbColumns, MediaStore.Video.Thumbnails.VIDEO_ID
33. + "=" + id, null, null);
34. if (thumbCursor.moveToFirst()) {
35. info.setThumbPath(thumbCursor.getString(thumbCursor
36. .getColumnIndex(MediaStore.Video.Thumbnails.DATA)));
37. }
38. info.setPath(cursor.getString(cursor
39. .getColumnIndexOrThrow(MediaStore.Video.Media.DATA)));
40. info.setTitle(cursor.getString(cursor
41. .getColumnIndexOrThrow(MediaStore.Video.Media.TITLE)));
43. info.setDisplayName(cursor.getString(cursor
44. .getColumnIndexOrThrow(MediaStore.Video.Media.DISPLAY_NAME)));
45. LogUtil.log(TAG, "DisplayName:"+info.getDisplayName());
46. info.setMimeType(cursor
47. .getString(cursor
48. .getColumnIndexOrThrow(MediaStore.Video.Media.MIME_TYPE)));
50. sysVideoList.add(info);
51. } while (cursor.moveToNext());
52. }
53. }

有一點需要注意的是：系統的媒體庫並不會在我們添加視頻文件後自動更新，我們如何去手動掃描媒體庫，或者重啟系統才能從媒體庫中得到更新的視頻文件：

sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, Uri.parse("file://"

+ Environment.getExternalStorageDirectory())));