android 通过uri截取指定大小的图片显示在imageview上

public class GridViewAdapter extends BaseAdapter {

protected List<Map<String, Object>> mlist;
protected Context mContext;
protected LayoutInflater mInflater = null;

public GridViewAdapter(Context context, List<Map<String, Object>> list) {
mlist = list;
mContext = context;
mInflater = LayoutInflater.from(context);
}

@Override
public int getCount() {
// TODO Auto-generated method stub
return mlist.size();
}

@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return mlist.get(position);
}

@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ViewHolder viewHolder = null;
if (null == convertView) {
viewHolder = new ViewHolder();
convertView = mInflater.inflate(R.layout.item_gridview, null);
viewHolder.imageButton = (ImageButton) convertView
.findViewById(R.id.imageButton1);
viewHolder.imageView = (ImageView) convertView
.findViewById(R.id.imageView1);
convertView.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) convertView.getTag();
}

if (!mlist.get(position).get("drawable").equals("") && mlist.size() < 6) {
viewHolder.imageView
.setImageResource(R.drawable.app_panel_add_icon_normal);
viewHolder.imageButton.setVisibility(View.GONE);

} else { //自动裁剪出制定大小的图片显示在imageview上
ContentResolver contentProvider = mContext.getContentResolver();
Uri uri01 = (Uri)mlist.get(position).get("uri");
Bitmap mBitmap = null;
try {
Bitmap bmp = BitmapFactory.decodeStream(contentProvider.openInputStream(uri01));
mBitmap = Bitmap.createScaledBitmap(bmp, 100, 100, true);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

viewHolder.imageView.setImageBitmap(mBitmap);
//			viewHolder.imageView.setImageURI((Uri) (mlist.get(position)
//					.get("uri")));
viewHolder.imageButton.setVisibility(View.VISIBLE);

}
final int i = position;
viewHolder.imageButton.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (mlist.size() == 5
&& mlist.get(4).get("drawable").equals("")) {
Map<String, Object> map = new HashMap<String, Object>();
map.put("drawable", R.drawable.ic_launcher);
mlist.add(map);
}
mlist.remove(i);
GridViewAdapter.this.notifyDataSetChanged();
}
});

return convertView;
}

static class ViewHolder {
ImageView imageView;
ImageButton imageButton;
}

}