Android联系人列表为json结构未获取

Question

我想获取Android联系人详细信息，例如：

[
    { 
        "id" : "1",
        "name" : "name1",
        "mobile":"1234567891"
    },
    { 
        "id" : "2",
        "name" : "name2",
        "mobile":"2222222222"
    }
]

所以我有代码这个代码

Contact.java

public class Contact {
    private String id;
    private String name;
    private String mobile;
    //setters & getters
    //constructors
}

AsyncTask执行后台任务然后显示列表

private class MyAsync extends AsyncTask<String, Void, String> {

    @SuppressWarnings("unused")
    @Override
    protected String doInBackground(String... params) {
        String serverResponse = "";
        try {
            serverResponse =contactDetail.fetchContacts1();
            Contact contact1= new Contact();
            contact1 = new Gson().fromJson(serverResponse, Contact.class);
            Log.i("serverResponse", serverResponse);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return serverResponse;
    }

    @Override
    protected void onPostExecute(String serverResponse) {           
        outputText.setText(serverResponse);
    }
}

这是获取联系方式的方法：

@SuppressWarnings({ "unchecked", "rawtypes" })
public String fetchContacts1() {
    Uri CONTENT_URI = ContactsContract.Contacts.CONTENT_URI;
    String HAS_PHONE_NUMBER = ContactsContract.Contacts.HAS_PHONE_NUMBER;
    ContentResolver contentResolver = getContentResolver();
    Cursor cursor = contentResolver.query(CONTENT_URI, null,null, null, null);  

     if (cursor.getCount() > 0) {
         while (cursor.moveToNext()) {
             int hasPhoneNumber = Integer.parseInt(cursor.getString(cursor.getColumnIndex( HAS_PHONE_NUMBER )));

             if (hasPhoneNumber > 0) {
                 Cursor phones = getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null,null,null, null);

                 while (phones.moveToNext()) {
                    id = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.RAW_CONTACT_ID));
                    name1 = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
                    mobile1 = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));

                    contact = new Contact(id,name1,mobile1);
                    dataToSend = new HashMap<>();
                    dataToSend.put("contact", new Gson().toJson(contact));
                    l1 = new LinkedList();
                    l1.add(dataToSend);                   
                    Log.i("Preeit", l1.toString());
                }
                phones.close(); 
            }
        }
    }
    return dataToSend.toString();
}

执行此代码后，在日志中我将获得所有联系人，如下所示：

     [{ 
          "id" : "1",
          "name" : "name1",
          "mobile":"1234567891"
            }]
    ...
.....
    [{ 
         "id" : "2",
         "name" : "name2",
         "mobile":"2222222222"
            }]

但是，在显示屏上我只收到一个号码细节，而不是所有的电话号码细节。

[{ "id" : "1","name" : "name1", "mobile":"1234567891"    } ]

我的代码有什么问题？