Develop Reference

Android Spinner setOnItemSelectedListener not working

I have made a spinner dynamically during a login process. I'd like to be able to return the value of the spinner when I click on an option but it doesn't seem to work.
I make the spinner here:
public Spinner page_spinner;
protected void onCreate(Bundle savedInstanceState){
...
page_spinner = (Spinner) findViewById(R.id.page_spinner);
...
//MAKE ARRAY HERE
GraphRequest requestPage = GraphRequest.newGraphPathRequest(
currentAccessToken,
"/me/accounts",
new GraphRequest.Callback() {
#Override
public void onCompleted(GraphResponse response) {
JSONArray jsonArray = null;
try {
jsonArray = response.getJSONObject().getJSONArray("data");
for(int i=0; i < jsonArray.length(); i++){
JSONObject page = jsonArray.getJSONObject(i);
String pageName = page.getString("name");
if(!pageName.equals("")) {
//Push names into the array
pages_array.add(pageName);
} else {
pages_array.clear();
}
}
} catch (JSONException e) {
e.printStackTrace();
}
}
});
Bundle pageParameters = new Bundle();
pageParameters.putString("fields", "name,access_token,picture{url}");
requestPage.setParameters(pageParameters);
requestPage.executeAsync();
...
ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>(StartPage.this, android.R.layout.simple_spinner_item, pages_array);
spinnerArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); // The drop down view
page_spinner.setAdapter(spinnerArrayAdapter);
spinnerArrayAdapter.notifyDataSetChanged();
then I try to use the spinner here:
page_spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
Log.d("***********", "THIS ");
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
Log.d("***********", "THIS ");
}
});
I don't ever get the Log.d or even if I made Toast there, it doesn't fire. Not sure why this is stopping and I'm not getting any errors.
Any ideas?

Declare the spinner as a global variable and without final
and try this:
page_spinner = (Spinner) findViewById(R.id.page_spinner);
...
//MAKE ARRAY HERE
GraphRequest requestPage = GraphRequest.newGraphPathRequest(
currentAccessToken,
"/me/accounts",
new GraphRequest.Callback() {
#Override
public void onCompleted(GraphResponse response) {
JSONArray jsonArray = null;
try {
jsonArray = response.getJSONObject().getJSONArray("data");
for(int i=0; i < jsonArray.length(); i++){
JSONObject page = jsonArray.getJSONObject(i);
String pageName = page.getString("name");
if(!pageName.equals("")) {
//Push names into the array
pages_array.add(pageName);
} else {
pages_array.clear();
}
}
} catch (JSONException e) {
e.printStackTrace();
}
ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>(StartPage.this, android.R.layout.simple_spinner_item, pages_array);
spinnerArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); // The drop down view
page_spinner.setAdapter(spinnerArrayAdapter);
spinnerArrayAdapter.notifyDataSetChanged();
}
});

Your error seems somewhat correct. You are not notifying adapter about the changes in dataset.
Firstly, Your request is executed Async. So, your code execution will continue to next lines. So I guess, a blank array (size 0) is passed to ArrayAdapter<> and then the adapter is set to Spinner and then you are calling notifyDataSetChanged().
I think you should call spinnerArrayAdapter.notifyDataSetChanged();as below:
#Override
public void onCompleted(GraphResponse response) {
JSONArray jsonArray = null;
try {
jsonArray = response.getJSONObject().getJSONArray("data");
for(int i=0; i < jsonArray.length(); i++){
JSONObject page = jsonArray.getJSONObject(i);
String pageName = page.getString("name");
if(!pageName.equals("")) {
//Push names into the array
pages_array.add(pageName);
} else {
pages_array.clear();
}
}
spinnerArrayAdapter.notifyDataSetChanged();
} catch (JSONException e) {
e.printStackTrace();
}

I've tested your codes and everything seems Right here. First I tried Adding 10 Items at spinner. Everything worked fine. And I tested adding List of String which contains only one Item.
List<String> spinnerArray = new ArrayList<String>();
spinnerArray.add("Item 1");
My OnItemSelectedListener
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(MainActivity.this, "Selected", Toast.LENGTH_SHORT).show();
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
But what happened is the code everything worked fine before was not working after because there is only one item in spinnerArray. Toast was shown when Activity loads and not called when item is selected. You may have the same issue there. So my suggestion is give priority to your Array which may contain only one item.

How do I refresh the data in the ListView?(json&http)

First of all , there is a listview in the activity named "user" . In the activity class, I have a thread that runs every 10 seconds. The thread calls a function which executes an AsyncTask . The AsyncTask does an http request and the response is parsed by a class named JSONparse . The data is then used in a listview inside a for loopwith a simple adapter.
The actual problem here is that the older data stay in the listview , and the same elements are added every 10 seconds.
The onPostExecute is inside the JSONparse class:
private static final String TAG_OS = "istekler";
private static final String TAG_VER = "isim";
private static final String TAG_NAME = "istek";
private static final String TAG_API = "mesaj";
protected void onPostExecute(JSONObject json) {
try {
// Getting JSON Array from URL
android = json.getJSONArray(TAG_OS);
for(int i = 0; i < android.length(); i++){
JSONObject c = android.getJSONObject(i);
// Storing JSON item in a Variable
String isim = c.getString(TAG_VER);
String mesaj = c.getString(TAG_NAME);
String istek = c.getString(TAG_API);
// Adding value HashMap key => value
HashMap<String, String> map = new HashMap<String, String>();
map.put(TAG_VER, isim);
map.put(TAG_NAME, mesaj);
map.put(TAG_API, istek);
oslist.add(map);
list=(ListView)findViewById(R.id.list);
ListAdapter adapter = new SimpleAdapter(user.this, oslist,
R.layout.list_v,
new String[] { TAG_VER,TAG_NAME, TAG_API }, new int[] {
R.id.isim,R.id.mesaj, R.id.istek});
list.setAdapter(adapter);
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Toast.makeText(user.this, "Parça: "+oslist.get(+position).get("istek"), Toast.LENGTH_SHORT).show();
}
});
}
} catch (JSONException e) {
e.printStackTrace();
}
}

on your code you just add new elements to your list. You should call oslist.clear() to remove the old data.

How to update listview after changing data in JSON?

Hello everyone and happy new year
I have JSON class where I retrieve some data that are retrieve from a database. The format of this JSON file is
{"people":[{"id":"15","first_name":"Theo","last_name":"Tziomakas","bio":"Hello from
Theo!!!","created":"2015-01-11 21:48:51"},
{"id":"16","first_name":"Jim","last_name":"Chytas","bio":"Hello from Chytas","created":"2015-01-11
21:53:42"}]}.
The idea is to retrieve the "first_name" and "second_name" in a listview. The "bio" should appear in another activity,but I don't know how to do that:(.
Here is my code.
public class MainActivity extends ActionBarActivity {
ListView list;
TextView fname;
TextView lname;
ArrayList<HashMap<String, String>> oslist = new ArrayList<HashMap<String, String>>();
//URL to get JSON Array
private static String url = "http://xxxxxxx/tutorials/index.php";
//JSON Node Names
private static final String TAG_OS = "people";
private static final String TAG_FIRST_NAME = "first_name";
private static final String TAG_SECOND_NAME = "last_name";
//private static final String TAG_BIO = "bio";
JSONArray android = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
oslist = new ArrayList<HashMap<String, String>>();
new JSONParse().execute();
}
private class JSONParse extends AsyncTask<String, String, JSONObject> {
private ProgressDialog pDialog;
#Override
protected void onPreExecute() {
super.onPreExecute();
fname = (TextView)findViewById(R.id.first_name);
lname = (TextView)findViewById(R.id.last_name);
//abio = (TextView)findViewById(R.id.bio);
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Getting Data ...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
#Override
protected JSONObject doInBackground(String... args) {
JSONParser jParser = new JSONParser();
// Getting JSON from URL
JSONObject json = jParser.getJSONFromUrl(url);
return json;
}
#Override
protected void onPostExecute(JSONObject json) {
pDialog.dismiss();
try {
// Getting JSON Array from URL
android = json.getJSONArray(TAG_OS);
for(int i = 0; i < android.length(); i++){
JSONObject c = android.getJSONObject(i);
// Storing JSON item in a Variable
String first_name = c.getString(TAG_FIRST_NAME);
String last_name = c.getString(TAG_SECOND_NAME);
//String bio = c.getString(TAG_BIO);
// Adding value HashMap key => value
HashMap<String, String> map = new HashMap<String, String>();
map.put(TAG_FIRST_NAME, first_name);
map.put(TAG_SECOND_NAME, last_name);
//map.put(TAG_BIO, bio);
oslist.add(map);
list=(ListView)findViewById(R.id.list);
ListAdapter adapter = new SimpleAdapter(MainActivity.this, oslist,
R.layout.list_v,
new String[] { TAG_FIRST_NAME,TAG_SECOND_NAME }, new int[] {
R.id.first_name,R.id.last_name});
list.setAdapter(adapter);
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
String bio = ((TextView) view.findViewById(R.id.bio))
.getText().toString();
switch (position) {
case 0:
Intent i = new Intent(MainActivity.this, SingleActivity.class);
i.putExtra("bio", bio);
startActivity(i);
break;
}
}
});
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
}
And finally I have the SecondActivity class,but nothing is shown when I click the first row of list.
public class SingleActivity extends ActionBarActivity {
TextView text;
JSONArray android = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_single);
text = (TextView)findViewById(R.id.text);
String bio = getIntent().getStringExtra("bio");
try {
JSONObject profileJSON = new JSONObject(bio);
android = profileJSON.getJSONArray(bio);
text.setText(""+android);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
Thank you.
EDIT:The problem I had is fixed. Now I want to do something else. Let us suppose that we update the data in an existing row by changing "first_name,"last_name" and finally bio. It is done very easily in phpmyadmin tool. The problem is that the updated row is not shown in the listview. I have to reinstall the app in order to see it. Any ideas in that?

try this ,
replace onPostExecute with this
protected void onPostExecute(JSONObject json) {
pDialog.dismiss();
try {
list=(ListView)findViewById(R.id.list);
// Getting JSON Array from URL
android = json.getJSONArray(TAG_OS);
for(int i = 0; i < android.length(); i++){
JSONObject c = android.getJSONObject(i);
// Storing JSON item in a Variable
String first_name = c.getString(TAG_FIRST_NAME);
String last_name = c.getString(TAG_SECOND_NAME);
//String bio = c.getString(TAG_BIO);
// Adding value HashMap key => value
HashMap<String, String> map = new HashMap<String, String>();
map.put(TAG_FIRST_NAME, first_name);
map.put(TAG_SECOND_NAME, last_name);
map.put(TAG_BIO, bio);
oslist.add(map);
}
ListAdapter adapter = new SimpleAdapter(MainActivity.this, oslist,
R.layout.list_v,
new String[] { TAG_FIRST_NAME,TAG_SECOND_NAME }, new int[] {
R.id.first_name,R.id.last_name});
list.setAdapter(adapter);
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
String bio =oslist.get(position).get(TAG_BIO);
// switch (position) {
// case 0:
Intent i = new Intent(MainActivity.this, SingleActivity.class);
i.putExtra("bio", bio);
startActivity(i);
break;
//}
}
});
} catch (JSONException e) {
e.printStackTrace();
}
}
and SingleActivity
text = (TextView)findViewById(R.id.text);
String bio = getIntent().getStringExtra("bio");
text.setText(bio );

Pay attention to what you put in the intent.
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
String bio = ((TextView) view.findViewById(R.id.bio))
.getText().toString();
switch (position) {
case 0:
Intent i = new Intent(MainActivity.this, SingleActivity.class);
i.putExtra("bio", bio);
startActivity(i);
break;
}
}
notice that you take the text from a text view and add it to and intent.
When you retreive it use it as if its a json object.
If you want the bio string, you could put that in a variable, and then send it to an intent with just the string.
for example
ListAdapter adapter = new SimpleAdapter(MainActivity.this, oslist,
R.layout.list_v,
new String[] { TAG_FIRST_NAME,TAG_SECOND_NAME }, new int[] {
R.id.first_name,R.id.last_name});
list.setAdapter(adapter);
String bio = c.getString("bio");
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
switch (position) {
case 0:
Intent i = new Intent(MainActivity.this, SingleActivity.class);
i.putExtra("bio", bio);
startActivity(i);
break;
}
}
});
when retrieving it its easier to just do it with
public class SingleActivity extends ActionBarActivity {
TextView text;
JSONArray android = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_single);
text = (TextView)findViewById(R.id.text);
String bio = getIntent().getStringExtra("bio");
text.settext(bio)
}
}
now there is prob some bugs in these example, since i have not java or android sdk installed on my computer

Having trouble adding string array to spinner entries

What I'd like to accomplish is the String array names[] be what you see in the spinner, but I cannot seem to figure out how to do this. I have tried looking off of other similar questions, but everything I try results in a crash in my app, saying that it is unable to instantiate the activity. Below, I have included the onPostExecute, where I am generating the string array, and also my addListenerOnSpinnerSelection() method. Any guidance would be great.
protected void onPostExecute(JSONObject json) {
try {
// Get JSON Object
JSONObject runes = json.getJSONObject(encodedId);
// Get JSON Array node
JSONArray rune = runes.getJSONArray("pages");
// Loop through pages, page names stored in string array
String[] name = new String[rune.length()];
String curr;
ArrayList<String> runePageNames = new ArrayList<String>();
for(int i = 0; i < rune.length(); i++) {
JSONObject c = rune.getJSONObject(i);
name[i] = c.getString(TAG_NAME);
curr = c.getString(TAG_CURRENT);
if(curr.equals("true"))
name[i] = name[i] + " [Active]";
runePageNames.add(name[i]);
Log.i(".........", name[i]);
}
adapter = new ArrayAdapter(this,
android.R.layout.simple_spinner_dropdown_item,
runePageNames);
addListenerOnSpinnerSelection();
// Set TextView
textName.setText(name[0]);
} catch (JSONException e) {
e.printStackTrace();
}
public void addListenerOnSpinnerSelection() {
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
((TextView) adapterView.getChildAt(0)).setTextColor(Color.parseColor("#C49246"));
Toast.makeText(adapterView.getContext(),
"Page Selected: " + adapterView.getItemAtPosition(i).toString(),
Toast.LENGTH_SHORT).show();
page = adapterView.getItemAtPosition(i).toString();
}
#Override
public void onNothingSelected(AdapterView<?> adapterView) {
}
});
}

How to retrieve value from ArrayList in android

I am trying to retrieve values from a json api and displaying then in a listView. The listView contains 3 elements and I am also implementing onItemClickListner() and when an Item is clicked it will display a detailed view related to that item. I am using an ArrayList to store all the json values. Now I want to retrieve a value from that ArrayList so that the OnClickListner() will get that value and from that value the detailed view will be displayed..
I am using AsyncTask to retrieve all the json values
#Override
protected String doInBackground(String... DATA) {
if(rqst_type.equals("top5"))
{
String url = DATA[1];
JsonParser jParser = new JsonParser();
JSONObject json = jParser.getJSONfromUrl(url);
try
{
JSONArray top5 = json.getJSONArray(TAG_TOP5);
public static ArrayList<HashMap<String, String>> top5List = new ArrayList<HashMap<String, String>>();
top5List.clear();
for(int i=0; i<top5.length(); i++)
{
Log.v(TAG_LOG, "Value of i: "+String.valueOf(i));
JSONObject t = top5.getJSONObject(i);
course_id = t.getString(TAG_CRSID);
created_date = t.getString(TAG_CRTDATE);
golfcourse_name = t.getString(TAG_GLFCRSNAME);
facilities = t.getString(TAG_FCLTY);
holes = t.getString(TAG_HOLES);
HashMap<String, String> map = new HashMap<String, String>();
map.put(TAG_CRSID, course_id);
map.put(TAG_CRTDATE, created_date);
map.put(TAG_GLFCRSNAME, golfcourse_name);
map.put(TAG_FCLTY, facilities);
map.put(TAG_HOLES, holes);
top5List.add(map);
Log.v(LoadingScreen.TAG_LOG, "top5List: "+String.valueOf(top5List));
}
}
catch(JSONException e)
{
Log.v(TAG_LOG, String.valueOf(e));
}
}
protected void onPostExecute(String result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
if(rqst_type.equals("top5"))
{
Intent in = new Intent(context, MyTop5.class);
in.putExtra(TAG_CRSID, course_id);
in.putExtra(TAG_CRTDATE, created_date);
in.putExtra(TAG_GLFCRSNAME, golfcourse_name);
in.putExtra(TAG_FCLTY, facilities);
in.putExtra(TAG_HOLES, holes);
Log.v(TAG_LOG, "Valuse to MyTop5: "+course_id+" "+created_date+" "+golfcourse_name+" "+
facilities+" "+holes);
context.startActivity(in);
}
This is the file to where I am displaying the list and the onItenClickListner()..
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.my_top5);
Intent in = getIntent();
golfcourse_name = in.getStringExtra(TAG_GLFCRSNAME);
course_id = in.getStringExtra(TAG_CRSID);
created_date = in.getStringExtra(TAG_CRTDATE);
facilities = in.getStringExtra(TAG_FCLTY);
holes = in.getStringExtra(TAG_HOLES);
Log.v(LoadingScreen.TAG_LOG, "course id: "+String.valueOf(course_id));
ListAdapter adapter = new SimpleAdapter(this, LoadingScreen.top5List, R.layout.top5_list,
new String[] { TAG_GLFCRSNAME, TAG_CRSID, TAG_CRTDATE, TAG_FCLTY, TAG_HOLES },
new int[] { R.id.top_golfname, R.id.top_courseid, R.id.top_createdate, R.id.top_fclty, R.id.top_holes });
setListAdapter(adapter);
Log.v(LoadingScreen.TAG_LOG, "course id: "+String.valueOf(course_id));
ListView lv = getListView();
lv.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
// TODO Auto-generated method stub
String url = "http://mygogolfteetime.com/iphone/viewdeal/127";
new LoadingScreen(MyTop5.this).execute("view_detail", url);
}
});
}
In the given URL I want to change the 127 to the value which is stored in the top5List.
String url = "http://mygogolfteetime.com/iphone/viewdeal/127";
The value I am trying to find in the top5List is the value of "course_id"
Thanks in advance..

top5List.get(your position).get(your Key);
With this code you can find the value on which you want to change.