Intent inten = new Intent(
                    Intent.ACTION_PICK,MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
            startActivityForResult(inten,21);




------------------------在onActivityResult中加入-------------------


Uri uri = data.getData();
            String[] filePath = { MediaStore.Images.Media.DATA };
            Cursor c = getContentResolver().query(uri, filePath,
                    null, null, null);
            c.moveToFirst();
            int columnIndex = c.getColumnIndex(filePath[0]);
            Log.e("autobot", columnIndex+"");
            String picturePath = c.getString(columnIndex);
            Log.e("autobot", picturePath);
            c.close();
            Bitmap  bitmap = ImageManager.decodeScaledBitmap(picturePath, 400, 200);
            image.setImageBitmap(bitmap);