是..
经过长时间的实验，我得到了答案：这是：
public class GridGallery extends Activity{ ArrayList<String>list; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.grid_gallery); DataModel dbModel = new DataModel(this); list = dbModel.selectAll(); GridView sdcardImages = (GridView) findViewById(R.id.sdcard); sdcardImages.setAdapter(new ImageAdapter(this)); } private class ImageAdapter extends baseAdapter { private final Context context; public ImageAdapter(Context localContext) { context = localContext; } public int getCount() { return list.size(); } public Object getItem(int position) { return position; } public long getItemId(int position) { return position; } public View getView(int position, View convertView, ViewGroup parent) { ImageView picturesView; if (convertView == null) { picturesView = new ImageView(context); if(list.get(position).contains(".jpg")) { bitmap = BitmapFactory.depreFile(list.get(position)); //Creation of Thumbnail of image } else if(list.get(position).contains(".mp4")) { bitmap = ThumbnailUtils.createVideoThumbnail(list.get(position), 0); //Creation of Thumbnail of video } picturesView.setScaleType(ImageView.ScaleType.FIT_CENTER); picturesView.setPadding(8, 8, 8, 8); picturesView.setLayoutParams(new GridView.LayoutParams(100, 100)); } else { picturesView = (ImageView)convertView; } return picturesView; } }}这对我来说很好
