我知道这个问题之前已被问过很多次但是我的问题有点不同。
我正在开发一个项目，我从Webservice获取JSON数据。在这个应用程序中我们可以投票到不同类型的食品项目，列表视图将根据投票排序（最大投票到最小投票）。在投票上单击任何列表项列表视图刷新并显示新的已排序项目列表。
我得到的JSON也提供了我投票的最新排序项目的索引位置。
所以现在我获得了投票项目的位置，我想在listview重新加载后将其滚动到该特定位置。我试过通过互联网提供的所有方法，但它不适合我。
请帮助这是我的代码。
这是我的RemoteDataTask异步类代码
public class RemoteDataTask extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
// Create a progressdialog
mProgressDialog = new ProgressDialog(ItemRankActivity.this);
// Set progressdialog title
mProgressDialog.setTitle("Loading All Awesomeness of " + title);
// Set progressdialog message
mProgressDialog
.setMessage("Wait.. While we Generating the Best Dishes for you.");
// Show progressdialog
mProgressDialog.show();
}
protected Void doInBackground(Void... params) {
ServiceHandler sh = new ServiceHandler();
// Making a request to url and getting response
String jsonStr = sh.makeServiceCall(URL, ServiceHandler.GET);
Log.d("Response: ", "> " + jsonStr);
if (jsonStr != null) {
try {
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
DishesArray = jsonObj.getJSONArray(TAG_DATA);
// looping through All Contacts
for (int i = 0; i < DishesArray.length(); i++) {
JSONObject c = DishesArray.getJSONObject(i);
arrayList.add(new ItemRankData(c.getString(TAG_PIC), c
.getString(TAG_TITLE), c
.getString(TAG_RESTAURANT), c
.getString(TAG_VOTES), c.getString(TAG_DISHID),
c.getString(TAG_FBID),
c.getString(TAG_IsVOTED), c
.getString(TAG_IsTOP), c
.getString(TAG_TopImage), c
.getString(TAG_Position)));
if (c.getString(TAG_IsTOP).equalsIgnoreCase("yes")) {
isTop = "yes";
Log.e("Is it on TOP", isTop);
if (c.getString(TAG_TopImage) != "") {
TopImageURL = c.getString(TAG_TopImage);
Log.e("Top image URL", TopImageURL);
VotedPosition = c.getString("position");
}
}
}
} catch (JSONException e) {
e.printStackTrace();
}
} else {
Log.e("ServiceHandler", "Couldn't get any data from the url");
}
return null;
}
@Override
protected void onPostExecute(Void result) {
Log.v("post", "After query post");
Picasso.with(mContext).load(TopImageURL).into(img_item_image);
PositionOfVote = Integer.parseInt(VotedPosition);
lv_items_lists.smoothScrollToPosition(PositionOfVote);
adapter.notifyDataSetChanged();
ClassDataManager.setListViewHeightBasedOnChildren(lv_items_lists);
Log.e("POST Execute Hit", "True");
mProgressDialog.dismiss();
}
}
我的自定义适配器类代码
public class ItemRankAdapter extends BaseAdapter {
String URL;
JSONArray BestCatogryArray = null;
private LayoutInflater inflater = null;
private ArrayList<ItemRankData> mlist;
private Context context;
ProgressDialog mProgressDialog;
private static String TAG_DATA = "data";
private static String TAG_VOTES = "votes";
JSONArray DishesArray = null;
String VOTES;
ViewHolder holder;
VOTING voting = new VOTING();
int POS;
public ItemRankAdapter(Context c, ArrayList<ItemRankData> mlist) {
this.context = c;
this.mlist = mlist;
inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
@Override
public int getCount() {
return mlist.size();
}
@Override
public Object getItem(int position) {
return position;
}
@Override
public long getItemId(int position) {
return position;
}
@SuppressLint("DefaultLocale")
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
ImageLoader imageLoader;
imageLoader = ImageLoader.getInstance();
if (convertView == null) {
convertView = inflater.inflate(R.layout.custom_item_rank, parent,
false);
holder = new ViewHolder();
holder.tv_item_serialNo = (TextView) convertView
.findViewById(R.id.tv_item_serialNo);
holder.tv_item_name = (TextView) convertView
.findViewById(R.id.tv_item_name);
holder.tv_item_restaurant = (TextView) convertView
.findViewById(R.id.tv_item_restaurant);
holder.tv_item_like_count = (TextView) convertView
.findViewById(R.id.tv_item_like_count);
holder.img_logo = (ImageView) convertView
.findViewById(R.id.img_logo);
holder.img_top_position = (ImageView) convertView
.findViewById(R.id.img_top_position);
holder.ll_likes = (LinearLayout) convertView
.findViewById(R.id.ll_likes);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
final ItemRankData rankData = mlist.get(position);
holder.tv_item_name.setText(rankData.itemName);
holder.tv_item_restaurant.setText(rankData.itemRestaurantName);
holder.tv_item_like_count.setText(rankData.itemLikes);
Log.e("Position Value is " + position,
" And The Name of Item Along with it is " + rankData.itemName);
String imageUrl = rankData.itemRetaurantLogo;
// imageLoader.displayImage(imageUrl, holder.img_logo);
Picasso.with(context).load(imageUrl).into(holder.img_logo);
if (position == 0) {
holder.tv_item_serialNo.setVisibility(View.GONE);
holder.img_top_position.setVisibility(View.VISIBLE);
} else {
holder.tv_item_serialNo.setVisibility(View.VISIBLE);
holder.img_top_position.setVisibility(View.GONE);
String s1 = String.format("%02d", (position + 1));
holder.tv_item_serialNo.setText(s1);
}
if (rankData.isVoted.equalsIgnoreCase("yes")) {
holder.ll_likes
.setBackgroundResource(R.drawable.top_selected_border);
holder.tv_item_like_count.setTextColor(context.getResources()
.getColor(R.color.text_selected));
} else {
holder.ll_likes.setBackgroundResource(R.drawable.normal_border);
holder.tv_item_like_count.setTextColor(context.getResources()
.getColor(R.color.text_normal));
}
holder.ll_likes.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String dishId = rankData.dishId;
URL = "http://Here I Write My URL?"
+ "dishid="
+ dishId
+ "&"
+ "fbid="
+ PrefrencesClass.getStringPreference(context,
Constants.APPSPREF, Constants.USER_ID);
new DataTask().execute();
((ItemRankActivity) context).UpdateRemoteDataRankActivity();
}
});
return convertView;
}
static class ViewHolder {
TextView tv_item_serialNo;
TextView tv_item_name;
TextView tv_item_restaurant;
TextView tv_item_like_count;
ImageView img_logo;
LinearLayout ll_add;
ImageView img_top_position;
LinearLayout ll_likes;
ImageView img_item_image;
}
//The Class to Send VOTE update URL to Server
private class DataTask extends AsyncTask<Void, Void, Void> {
protected Void doInBackground(Void... params) {
ServiceHandler sh = new ServiceHandler();
// Making a request to url and getting response
String jsonStr = sh.makeServiceCall(URL, ServiceHandler.GET);
Log.d("Response: ", "> " + jsonStr);
return null;
}
}}
请帮助我，我正在努力解决这个问题的方法和地点 任何帮助都会很棒:)
答案 0 :(得分：2)
lv_items_lists.setSelection(PositionOfVote);
在
后试试adapter.notifyDataSetChanged();
我希望它能帮到你
答案 1 :(得分：0)
试试这个。
lv_items_lists.setSelection(PositionOfVote);
而不是
lv_items_lists.smoothScrollToPosition(PositionOfVote);
我希望它有所帮助！