Android 无法通过getFirstInBackGround从分析中检索数据

我试图从名为Location的Parse类中检索数据，其中有两列

latitude

和

longitude

。还有一个名为

Username

的列，其中存储了用户的

objectId

。 我正在将这个

用户名与程序中的用户名进行匹配，但是
getFirstInBackground
中使用的“done”方法似乎没有执行

代码如下：

for (int i = 0; i < recipient_id.size(); i++) {

    ParseQuery<ParseObject> query = ParseQuery.getQuery("Location");
                query.whereEqualTo("Username", recipient_id.get(i).toString());
                query.getFirstInBackground(new GetCallback<ParseObject>() {
                    @Override
                    public void done(ParseObject object, ParseException e) {
                        if(object==null) {

                            //Toast.makeText(getApplicationContext(), locations.toString(), Toast.LENGTH_LONG).show();
                        }
                        else{
                            //Toast.makeText(getApplicationContext(), "Error", Toast.LENGTH_LONG).show();
                            //e.printStackTrace();
                            lat = (double) object.get("latitude");
                            longi = (double) object.get("longitude");
                            Log.e("Latitude", lat+"");
                            locations.add(lat);
                            locations.add(longi);
                            Log.e("Locations", locations+"");
                        }
                    }
                });
}
Log.e("Locations", locations+"");

for（int i=0；i

当我检查日志时，位置显示为空。字符串
recipient\u id
的
ArrayList
以随机顺序包含用户的
objectId
s


我尝试将
纬度
和
经度
数据输入到用户类中，但问题仍然是一样的

编辑：我使用
getInBackground
来查询
ParseUser
而不是
getFirstInBackground
尝试这样做。
首先，您可以将用户存储在解析查询数组列表中，如

// Other Wise Try on this way
    for (int i = 0; i < recipient_id.size(); i++) {

        ParseQuery<ParseObject> query = ParseQuery.getQuery("Location");
        query.whereEqualTo("Username", recipient_id.get(i).toString());
        query.findInBackground(new FindCallback<ParseObject>() {
            @Override
            public void done(List<ParseObject> list, ParseException e) {
                // TODO Auto-generated method stub
                if (e == null) {
                    // Success
                    lat = (double) object.get("latitude");
                    longi = (double) object.get("longitude");
                    Log.e("Latitude", lat + "");
                    locations.add(lat);
                    locations.add(longi);
                    Log.e("Locations", locations + "");
                } else {
                    // Fail
                    // in case its fail that a time check error like
                    Log.e("get Error", " Message " + e.getMessage());
                }

            }
        });

//其他明智的做法是这样做
对于（int i=0；i

尝试其他方式，如

List<ParseQuery<ParseObject>> addQuery = new ArrayList<ParseQuery<ParseObject>>();
    // first store in parse query array
    for (int i = 0; i < recipient_id.length; i++) {
        ParseQuery<ParseObject> query = ParseQuery.getQuery("Location");
        query.whereEqualTo("Username", recipient_id.get(i).toString());
        addQuery.add(query);
    }

    ParseQuery<ParseObject> fetch = ParseQuery.or(addQuery);
    fetch.findInBackground(new FindCallback<ParseObject>() {

        @Override
        public void done(List<ParseObject> list, ParseException e) {
            // TODO Auto-generated method stub
            if (e == null) {
                // Success
            } else {
                // Fail
                // in case its fail that a time check error like
                Log.e("get Error", " Message " + e.getMessage());
            }

        }
    });

List addQuery=new ArrayList（）；
//解析查询数组中的第一个存储
for（int i=0；i
试着这样做。
首先，您可以将用户存储在解析查询数组列表中，如

// Other Wise Try on this way
    for (int i = 0; i < recipient_id.size(); i++) {

        ParseQuery<ParseObject> query = ParseQuery.getQuery("Location");
        query.whereEqualTo("Username", recipient_id.get(i).toString());
        query.findInBackground(new FindCallback<ParseObject>() {
            @Override
            public void done(List<ParseObject> list, ParseException e) {
                // TODO Auto-generated method stub
                if (e == null) {
                    // Success
                    lat = (double) object.get("latitude");
                    longi = (double) object.get("longitude");
                    Log.e("Latitude", lat + "");
                    locations.add(lat);
                    locations.add(longi);
                    Log.e("Locations", locations + "");
                } else {
                    // Fail
                    // in case its fail that a time check error like
                    Log.e("get Error", " Message " + e.getMessage());
                }

            }
        });

//其他明智的做法是这样做
对于（int i=0；i

尝试其他方式，如

List<ParseQuery<ParseObject>> addQuery = new ArrayList<ParseQuery<ParseObject>>();
    // first store in parse query array
    for (int i = 0; i < recipient_id.length; i++) {
        ParseQuery<ParseObject> query = ParseQuery.getQuery("Location");
        query.whereEqualTo("Username", recipient_id.get(i).toString());
        addQuery.add(query);
    }

    ParseQuery<ParseObject> fetch = ParseQuery.or(addQuery);
    fetch.findInBackground(new FindCallback<ParseObject>() {

        @Override
        public void done(List<ParseObject> list, ParseException e) {
            // TODO Auto-generated method stub
            if (e == null) {
                // Success
            } else {
                // Fail
                // in case its fail that a time check error like
                Log.e("get Error", " Message " + e.getMessage());
            }

        }
    });

List addQuery=new ArrayList（）；
//解析查询数组中的第一个存储
for（int i=0；i