希望有人可以帮助我。由于某种原因让我失望，UI中的微调器没有填充任何数据。在8小时阅读Stack Overflow问题和答案之后，我已经搜索了高低，并尝试了无数的修复，但没有运气。来自服务器的烘焙返回数据返回正常，但该数据未被转发到微调器中。
我没有得到任何编译时间或运行时错误，所以要么我没有正确处理JSON，要么我重写在某处分配给微调器的内容，不确定。
查询的代码是
<?php
include 'Dbconf.php';
$con = mysqli_connect($HostName,$HostUser,$HostPass,$DatabaseName);
// Get list of current events
//$qry = "SELECT EventID,EventName,EventDate FROM skid_event WHERE IsOpen ='1'";
$qry = "SELECT EventID,EventName,EventDate FROM skid_event";
$result=mysqli_query($con,$qry);
if ($result=mysqli_query($con,$qry))
{
$rowcount=mysqli_num_rows($result);
if ($rowcount > 0)
{
$rows = array();
while($r = mysqli_fetch_assoc($result)) {
$rows[] = $r;
}
print json_encode($rows);
//$row=mysqli_fetch_array($result,MYSQLI_ASSOC);
//echo json_encode($row);
mysqli_free_result($result);
mysqli_close($con);
exit();
}
else
{
echo "Fail";
}
}
else
{
echo 'Failed';
}
mysqli_close($con);
?>
它产生以下格式化的JSON结果，这是我期望的
[{“EventID”：“1”，“EventName”：“Burnout King”，“EventDate”：“2017-04-14”}，{“EventID”：“2”，“EventName”：“Gazzanats WA”， “EVENTDATE”： “2018年2月23日”}]
以上是我在应用程序中响应服务器响应时的情况。
片段代码如下所示
import android.content.Context;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
public class FindEventFragment extends Fragment{
public static final String TAG = "FindEventFragment";
private VolleyHelper mInstance;
private ArrayList<String> eventList;
private JSONArray result;
private Spinner eventNameSpinner;
private TextView eventDate;
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
private String mParam1;
private String mParam2;
private OnFragmentInteractionListener mListener;
public FindEventFragment() {
// Required empty public constructor
}
public static FindEventFragment newInstance(String param1, String param2) {
FindEventFragment fragment = new FindEventFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
}
public void onStart() {
super.onStart();
// Instantiate the RequestQueue from VolleyHelper
mInstance = VolleyHelper.getInstance(getActivity().getApplicationContext());
// API
connectApi();
}
@Override
public void onStop () {
super.onStop();
if (mInstance.getRequestQueue() != null) {
mInstance.getRequestQueue().cancelAll(TAG);
}
}
private void connectApi() {
String url = "http://gblakes.ddns.net/get_events.php";
StringRequest stringRequest = new StringRequest(Request.Method.GET, url,
new Response.Listener<String>() {
@Override
public void onResponse(String ServerResponse) {
Toast.makeText(getActivity().getApplicationContext(), ServerResponse, Toast.LENGTH_LONG).show();
JSONObject j = null;
try {
j = new JSONObject(ServerResponse);
result = j.getJSONArray("EventName");
eventDetails(result);
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError volleyError) {
Toast.makeText(getActivity().getApplicationContext(), volleyError.toString(), Toast.LENGTH_LONG).show();
}
});
if (mInstance != null) {
// Add a request to your RequestQueue.
mInstance.addToRequestQueue(stringRequest);
// Start the queue
mInstance.getRequestQueue().start();
}
}
private void eventDetails(JSONArray j) {
for (int i = 0; i < j.length(); i++) {
try {
JSONObject json = j.getJSONObject(i);
eventList.add(json.getString("EventName"));
} catch (JSONException e) {
//e.printStackTrace();
Log.d(TAG, e.toString());
}
}
/**check this it could be wrong since Im trying to set an adapter that contains no data yet*/
ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(getActivity(),android.R.layout.simple_spinner_item, eventList);
dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
eventNameSpinner.setAdapter(dataAdapter);
eventNameSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener(){
@Override
public void onItemSelected(AdapterView<?> parent, View v, int position, long id) {
//Setting the value to textview for a selected item
eventDate.setText(getEventDate(position));
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
eventDate.setText("test me");
}
});
// arrayList.add(0,"Select Event");
//eventNameSpinner.setAdapter(new ArrayAdapter<String>(getActivity().getApplicationContext(), android.R.layout.simple_spinner_dropdown_item, eventList));
}
private String getEventID(int position) {
String eventID = "";
try {
//Getting object of given index
JSONObject json = result.getJSONObject(position);
//Fetching name from that object
eventID = json.getString("EventID");
} catch (JSONException e) {
e.printStackTrace();
}
//Returning the name
return eventID;
}
private String getEventDate(int position){
String eventDate="";
try {
JSONObject json = result.getJSONObject(position);
eventDate = json.getString("EventDate");
} catch (JSONException e) {
e.printStackTrace();
}
return eventDate;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View v = inflater.inflate(R.layout.fragment_find_event,container,false);
eventNameSpinner = (Spinner) v.findViewById(R.id.spinEventPicker);
eventNameSpinner = new Spinner(getActivity().getApplicationContext());
eventDate = (TextView) v.findViewById(R.id.textEventDate);
eventDate.setText("test me");
return v;
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
/**
* This interface must be implemented by activities that contain this
* fragment to allow an interaction in this fragment to be communicated
* to the activity and potentially other fragments contained in that
* activity.
* <p>
* See the Android Training lesson <a href=
* "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
}
片段xml看起来像这样
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:id="@+id/textEventName">
<Spinner
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/spinEventPicker"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Large Text"
android:id="@+id/textEventDate"
android:layout_marginTop="49dp"
android:layout_below="@+id/spinEventPicker"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
</RelativeLayout>
如果有人能够指出我做错了什么，并且可能提出的解决办法很棒。
TIA
答案 0 :(得分：0)
你好像是在实例化你的Spinner两次，首先（正确的方式）引用布局，第二次创建一个全新的Spinner对象。
eventNameSpinner = (Spinner) v.findViewById(R.id.spinEventPicker);
eventNameSpinner = new Spinner(getActivity().getApplicationContext());
我相信如果您删除了这两行代码的第二行（在onCreateView中找到），它应该可以工作。
修改
似乎还需要对JSON的处理进行一些更改。首先，您需要更改ServerResponse String的使用。
try {
result = new JSONArray(ServerResponse);
eventDetails(result);
} catch (JSONException e) {
e.printStackTrace();
}
然后你需要改变你访问数组的方式。
for (int i = 0; i < j.length(); i++) {
try {
JSONObject json = j.getJSONObject(i);
eventList.add(json.getString("EventName") + json.getString("EventDate");
} catch (JSONException e) {
//e.printStackTrace();
Log.d(TAG, e.toString());
}
}
这应该可行。