Displaying xml float data - android

I am trying to create an earthquake watcher app but I can't seem to get the coordinates and other sections from the XML URL to show on my activity when I load the project I know that they are of type float. I have tried different methods and I have no errors on the console so it must be something with the way that I am calling it??
I have added some output and images
package ja.example.mpd1starterearth;
import android.app.ProgressDialog;
import android.content.Intent;
import android.net.Uri;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
public class MainActivity extends AppCompatActivity {
ListView lvRss;
ArrayList<String> titles;
ArrayList<String> links;
ArrayList<Double> lat;
ArrayList<Double> lon;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lvRss = (ListView) findViewById(R.id.lvRss);
titles = new ArrayList<String>();
links = new ArrayList<String>();
lat = new ArrayList<Double>();
lon = new ArrayList<Double>();
lvRss.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Uri uri = Uri.parse(links.get(position));
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
}
});
new ProcessInBackground().execute();
}
public InputStream getInputStream(URL url)
{
try
{
//openConnection() returns instance that represents a connection to the remote object referred to by the URL
//getInputStream() returns a stream that reads from the open connection
return url.openConnection().getInputStream();
}
catch (IOException e)
{
return null;
}
}
public class ProcessInBackground extends AsyncTask<Integer, Void, Exception>
{
ProgressDialog progressDialog = new ProgressDialog(MainActivity.this);
Exception exception = null;
#Override
protected void onPreExecute() {
super.onPreExecute();
progressDialog.setMessage("Busy loading rss feed...please wait...");
progressDialog.show();
}
#Override
protected Exception doInBackground(Integer... params) {
try
{
URL url = new URL("http://quakes.bgs.ac.uk/feeds/MhSeismology.xml");
//creates new instance of PullParserFactory that can be used to create XML pull parsers
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
//Specifies whether the parser produced by this factory will provide support
//for XML namespaces
factory.setNamespaceAware(false);
//creates a new instance of a XML pull parser using the currently configured
//factory features
XmlPullParser xpp = factory.newPullParser();
// We will get the XML from an input stream
xpp.setInput(getInputStream(url), "UTF_8");
/* We will parse the XML content looking for the "<title>" tag which appears inside the "<item>" tag.
* We should take into consideration that the rss feed name is also enclosed in a "<title>" tag.
* Every feed begins with these lines: "<channel><title>Feed_Name</title> etc."
* We should skip the "<title>" tag which is a child of "<channel>" tag,
* and take into consideration only the "<title>" tag which is a child of the "<item>" tag
*
* In order to achieve this, we will make use of a boolean variable called "insideItem".
*/
boolean insideItem = false;
// Returns the type of current event: START_TAG, END_TAG, START_DOCUMENT, END_DOCUMENT etc..
int eventType = xpp.getEventType(); //loop control variable
while (eventType != XmlPullParser.END_DOCUMENT)
{
//if we are at a START_TAG (opening tag)
if (eventType == XmlPullParser.START_TAG)
{
//if the tag is called "item"
if (xpp.getName().equalsIgnoreCase("item"))
{
insideItem = true;
}
//if the tag is called "title"
else if (xpp.getName().equalsIgnoreCase("title"))
{
if (insideItem)
{
// extract the text between <title> and </title>
titles.add(xpp.nextText());
}
}
//if the tag is called "link"
else if (xpp.getName().equalsIgnoreCase("link"))
{
if (insideItem)
{
// extract the text between <link> and </link>
links.add(xpp.nextText());
}
}
else if(xpp.getName().equalsIgnoreCase("geo:lat")){
if(insideItem){
//extract the text between <geo:lat> and </geo:lat>
lat.add(Double.valueOf(xpp.nextText()));
}
}
else if(xpp.getName().equalsIgnoreCase("geo:long")){
if(insideItem) {
//extract the text between <geo:lat> and </geo:lat>
lon.add(Double.valueOf(xpp.nextText()));;
} }
}
//if we are at an END_TAG and the END_TAG is called "item"
else if (eventType == XmlPullParser.END_TAG && xpp.getName().equalsIgnoreCase("item"))
{
insideItem = false;
}
eventType = xpp.next(); //move to next element
}
}
catch (MalformedURLException e)
{
exception = e;
}
catch (XmlPullParserException e)
{
exception = e;
}
catch (IOException e)
{
exception = e;
}
return exception;
}
#Override
protected void onPostExecute(Exception s) {
super.onPostExecute(s);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_list_item_1, titles);
lvRss.setAdapter(adapter);
progressDialog.dismiss();
}
}
}

Your code to parse data from the URL is totally correct. You do not see all data all the activity because this line of code.
ArrayAdapter<String> adapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_list_item_1, titles);
You pass titles arraylist to the adapter, that why you only see all title xml value in the activity.
Solution: The simple way is format the data which connect from 4 array list titles, links, lat, lon.
/**
* This method will format data from titles, links, lat, lon arraylist.
*/
private List<String> formatDataBeforeDisplayOnListView(){
List<String> list = new ArrayList<>();
StringBuilder sb = new StringBuilder();
int size = titles.size();
for (int i = 0; i < size; ++i) {
String title = titles.get(i);
String link = links.get(i);
Double geoLat = lat.get(i);
Double getLon = lon.get(i);
sb.append("title: ").append(title).append("\n")
.append("link: ").append(link).append("\n")
.append("geo-lat: ").append(geoLat).append("\n")
.append("geo-lon: ").append(getLon);
list.add(sb.toString());
}
return list;
}
Then change your code to
// Comment-out this line
// ArrayAdapter<String> adapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_list_item_1, titles);
List<String> items = formatDataBeforeDisplayOnListView();
ArrayAdapter<String> adapter = new ArrayAdapter<>(MainActivity.this, android.R.layout.simple_list_item_1, items);
Note: If you want to display each item listview in a better design/UI then you should write a custom adapter class instead of ArrayAdapter.
Updated: Based on Jase's comment
First, declare a new class named Item
public class Item {
private String title;
private String link;
private Double lat;
private Double lon;
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getLink() {
return link;
}
public void setLink(String link) {
this.link = link;
}
public Double getLat() {
return lat;
}
public void setLat(Double lat) {
this.lat = lat;
}
public Double getLon() {
return lon;
}
public void setLon(Double lon) {
this.lon = lon;
}
#Override
public String toString() {
return (new StringBuilder()).append("title: ").append(title).append("\n")
.append("link: ").append(link).append("\n")
.append("geo-lat: ").append(lat).append("\n")
.append("geo-lon: ").append(lon).toString();
}
}
Then, change your activity code to
public class MainActivity extends AppCompatActivity {
ListView lvRss;
ArrayList<Item> mItems = new ArrayList<>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lvRss = (ListView) findViewById(R.id.lvRss);
lvRss.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
// TODO: Process clicked item here
Item item = (Item) parent.getItemAtPosition(position);
Uri uri = Uri.parse(item.getLink());
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
}
});
new ProcessInBackground().execute();
}
public InputStream getInputStream(URL url) {
try {
//openConnection() returns instance that represents a connection to the remote object referred to by the URL
//getInputStream() returns a stream that reads from the open connection
return url.openConnection().getInputStream();
} catch (IOException e) {
return null;
}
}
public class ProcessInBackground extends AsyncTask<Integer, Void, Exception> {
ProgressDialog progressDialog = new ProgressDialog(MainActivity.this);
Exception exception = null;
#Override
protected void onPreExecute() {
super.onPreExecute();
progressDialog.setMessage("Busy loading rss feed...please wait...");
progressDialog.show();
}
#Override
protected Exception doInBackground(Integer... params) {
try {
URL url = new URL("http://quakes.bgs.ac.uk/feeds/MhSeismology.xml");
//creates new instance of PullParserFactory that can be used to create XML pull parsers
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
//Specifies whether the parser produced by this factory will provide support
//for XML namespaces
factory.setNamespaceAware(false);
//creates a new instance of a XML pull parser using the currently configured
//factory features
XmlPullParser xpp = factory.newPullParser();
// We will get the XML from an input stream
xpp.setInput(getInputStream(url), "UTF_8");
/* We will parse the XML content looking for the "<title>" tag which appears inside the "<item>" tag.
* We should take into consideration that the rss feed name is also enclosed in a "<title>" tag.
* Every feed begins with these lines: "<channel><title>Feed_Name</title> etc."
* We should skip the "<title>" tag which is a child of "<channel>" tag,
* and take into consideration only the "<title>" tag which is a child of the "<item>" tag
*
* In order to achieve this, we will make use of a boolean variable called "insideItem".
*/
boolean insideItem = false;
// Returns the type of current event: START_TAG, END_TAG, START_DOCUMENT, END_DOCUMENT etc..
int eventType = xpp.getEventType(); //loop control variable
Item item = null;
while (eventType != XmlPullParser.END_DOCUMENT) {
//if we are at a START_TAG (opening tag)
if (eventType == XmlPullParser.START_TAG) {
//if the tag is called "item"
if (xpp.getName().equalsIgnoreCase("item")) {
insideItem = true;
item = new Item();
}
//if the tag is called "title"
else if (xpp.getName().equalsIgnoreCase("title")) {
if (insideItem) {
// extract the text between <title> and </title>
item.setTitle(xpp.nextText());
}
}
//if the tag is called "link"
else if (xpp.getName().equalsIgnoreCase("link")) {
if (insideItem) {
// extract the text between <link> and </link>
item.setLink(xpp.nextText());
}
} else if (xpp.getName().equalsIgnoreCase("geo:lat")) {
if (insideItem) {
//extract the text between <geo:lat> and </geo:lat>
item.setLat(Double.valueOf(xpp.nextText()));
}
} else if (xpp.getName().equalsIgnoreCase("geo:long")) {
if (insideItem) {
//extract the text between <geo:lat> and </geo:lat>
item.setLon(Double.valueOf(xpp.nextText()));
}
}
}
//if we are at an END_TAG and the END_TAG is called "item"
else if (eventType == XmlPullParser.END_TAG && xpp.getName().equalsIgnoreCase("item")) {
insideItem = false;
mItems.add(item);
}
eventType = xpp.next(); //move to next element
}
} catch (MalformedURLException e) {
exception = e;
} catch (XmlPullParserException e) {
exception = e;
} catch (IOException e) {
exception = e;
}
return exception;
}
#Override
protected void onPostExecute(Exception s) {
super.onPostExecute(s);
ArrayAdapter<Item> adapter = new ArrayAdapter<>(MainActivity.this, android.R.layout.simple_list_item_1, mItems);
lvRss.setAdapter(adapter);
progressDialog.dismiss();
}
}
}

You are comparing tag name with space in it thus equalsIgnoreCase() will always return false as geo:lang will not be equal to geo :lat.
Just test this code.
String s = "geo:lang";
System.out.println(""+s.equalsIgnoreCase("geo :long"));
You need to remove space in between o and : for both cases eg.equalsIgnoreCase("geo:long")

Related

Android TableView with MSSQL

I am busy with trying to get an array which i get from MSSQL to display in a table view form in my application. I have tried to google it but i cant seem to find an example of this. I have tried it but i am running into one small error.
I get the following error Cannot resolve constructor:Simpletabledata adapter[package.mainactivity, package.itemarray]
Here is my mainactivy.java class:
public class MainActivity extends AppCompatActivity {
static String[] spaceProbeHeaders={"Name"};
private ArrayList<ClassListItems> itemArrayList; //List items Array
private MyAppAdapter myAppAdapter; //Array Adapter
final TableView<String[]> tableView = (TableView<String[]>) findViewById(R.id.tableView);
private boolean success = false; // boolean
Connection conn; // Connection Class Initialization
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tableView.setHeaderBackgroundColor(Color.parseColor("#777777"));
tableView.setHeaderAdapter(new SimpleTableHeaderAdapter(this,spaceProbeHeaders));
tableView.setColumnCount(4);
itemArrayList = new ArrayList<ClassListItems>(); // Arraylist Initialization
// Calling Async Task
SyncData orderData = new SyncData();
orderData.execute("");
}
// Async Task has three overrided methods,
private class SyncData extends AsyncTask<String, String, String>
{
String msg = "Internet/DB_Credentials/Windows_FireWall_TurnOn Error, See Android Monitor in the bottom For details!";
ProgressDialog progress;
#Override
protected void onPreExecute() //Starts the progress dailog
{
progress = ProgressDialog.show(MainActivity.this, "Synchronising",
"Tableview Loading! Please Wait...", true);
}
#Override
protected String doInBackground(String... strings) // Connect to the database, write query and add items to array list
{
try
{
ConnectionClass conStr=new ConnectionClass();
conn =conStr.connectionclass();
//Connection Object
if (conn == null)
{
success = false;
}
else {
// Change below query according to your own database.
String query = "SELECT customer_first_name FROM cc_customer";
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery(query);
if (rs != null) // if resultset not null, I add items to itemArraylist using class created
{
while (rs.next())
{
try {
itemArrayList.add(new ClassListItems(rs.getString("customer_first_name")));
} catch (Exception ex) {
ex.printStackTrace();
}
}
msg = "Found";
success = true;
} else {
msg = "No Data found!";
success = false;
}
}
} catch (Exception e)
{
e.printStackTrace();
Writer writer = new StringWriter();
e.printStackTrace(new PrintWriter(writer));
msg = writer.toString();
success = false;
}
return msg;
}
#Override
protected void onPostExecute(String msg) // disimissing progress dialoge, showing error and setting up my listview
{
progress.dismiss();
Toast.makeText(MainActivity.this, msg + "", Toast.LENGTH_LONG).show();
if (success == false)
{
}
else {
try {
//myAppAdapter = new MyAppAdapter(itemArrayList, MainActivity.this);
tableView.setDataAdapter(new SimpleTableDataAdapter(MainActivity.this,itemArrayList ));
} catch (Exception ex)
{
}
}
}
}
and here is my classlist.java file:
public class ClassListItems
{
public String name; //Name
public ClassListItems(String name)
{
this.name = name;
}
public String getName() {
return name;
}
Update
N.B: OP is using SortableTableView Library.
You need to import the following to solve Cannot resolve constructor:SimpleTableDataAdapter-
import de.codecrafters.tableview.toolkit.SimpleTableDataAdapter;
Original
Do you have SimpleTableDataAdapter class in your project? It seems it can't find the class so it is not in the same package. If it is in different package, you need to import it.
And on a different note, your .java file names should match the class name
And on another different note, have you tested that itemArrayList is actually populating? For Android-MSSQL, here is a tutorial pointer -
https://parallelcodes.com/connect-android-to-ms-sql-database-2/
There are many tutorials if you google it.

Custom adapter not updating gridview

I am writing an app to pull movie data from the MovieDB api and display the information in a GridView.
When the app first loads I would expect the view to populate initially, but it does not. I have a sort option in the menu bar and when the sort option is set the first time the GridView is populated by movies in order of popularity, as it should initially, but regardless of what sort criteria is actually selected.
I have used the logs to determine that the correct data is being retrieved from the API and being processed properly, so I have to assume that the adapter is not updating the view properly.
Why isn't the view showing initially or updating as it should?
FilmFragment.java:
public class FilmFragment extends Fragment {
private ArrayList<FilmParcelable> filmParcels = new ArrayList<FilmParcelable>();
private ImageAdaptor mFilmAdaptor;
protected String[] sortOptions = {
"popularity.desc",
"vote_average.desc"
};
protected String sortBy = sortOptions[0];
private final String LOG_TAG = FilmFragment.class.getSimpleName();
public FilmFragment() {
}
#Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
if (savedInstanceState == null || !savedInstanceState.containsKey("films")){
updateFilms();
mFilmAdaptor = new ImageAdaptor(getActivity(),filmParcels);
} else {
filmParcels = savedInstanceState.getParcelableArrayList("films");
mFilmAdaptor = new ImageAdaptor(getActivity(),filmParcels);
}
// allow fragment to handle menu events
setHasOptionsMenu(true);
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater){
inflater.inflate(R.menu.filmfragment, menu);
}
public boolean onOptionsItemSelected(MenuItem item){
//Handle action bar item clicks. The action bar will
//automatically handle clicks on the Home/Up button, so long
//as you specify a parent activity in AndroidManifest.xml
int id = item.getItemId();
if (id == R.id.action_sort){
showSortDialog();
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onSaveInstanceState(Bundle outState){
outState.putParcelableArrayList("films", filmParcels);
super.onSaveInstanceState(outState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
// Find GridView to populate with poster images
GridView gridView = (GridView) rootView.findViewById(R.id.gridView);
// Set the adaptor of the GridView to my ImageAdaptor
gridView.setAdapter(mFilmAdaptor);
updateAdaptor();
return rootView;
}
// Update movie data in case there is a change in the "sort by" option
// Or the fragment is started with no saved data
public void updateFilms(){
new FetchFilmTask().execute();
}
public void updateAdaptor(){
mFilmAdaptor.clear();
mFilmAdaptor.addAll(filmParcels);
mFilmAdaptor.notifyDataSetChanged();
}
// Show dialog sort pop up
public void showSortDialog(){
DialogFragment dialog = new SortDialog();
dialog.setTargetFragment(this, 0);
dialog.show(getActivity().getSupportFragmentManager(), "SortDialog");
}
// If a fragment or activity called by this fragment returns to this fragment,
// Get the information returned via the intent
public void onActivityResult(int requestCode, int resultCode, Intent data){
if (requestCode == 0){
int mSelected = data.getIntExtra("Selected Option", -1);
if (mSelected != -1){
sortBy = sortOptions[mSelected];
updateFilms();
updateAdaptor();
}
}
}
// Class to get JSON data from The Movie Database API
public class FetchFilmTask extends AsyncTask<Void, Void, FilmParcelable[]> {
private final String LOG_TAG = FetchFilmTask.class.getSimpleName();
private final String MOVIE_DB_API_KEY = "e1968ef8ba074d7d5bf07a59de8b2310";
protected FilmParcelable[] doInBackground(Void... params){
// These two need to be declared outside the try/catch
// so that they can be closed in the finally block.
HttpURLConnection urlConnection = null;
BufferedReader reader = null;
// Will contain raw JSON response as a string
String movieDBStr = null;
try {
// Construct URL for Movie DB query
Uri.Builder builder = new Uri.Builder();
builder.scheme("http")
.authority("api.themoviedb.org")
.appendPath("3")
.appendPath("discover")
.appendPath("movie")
.appendQueryParameter("api_key", MOVIE_DB_API_KEY)
.appendQueryParameter("sort_by", sortBy);
String myUrl = builder.build().toString();
Log.d(LOG_TAG, myUrl);
URL url = new URL(myUrl);
// Create the request to The Movie DB, and open the connection
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
// Read the input stream into a String
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if (inputStream == null){
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
// Since it's JSON, adding a newline isn't necessary (it won't affect parsing)
// But it does make debugging a *lot* easier if you print out the completed
// buffer for debugging.
buffer.append(line + "\n");
}
if (buffer.length() == 0) {
return null;
}
movieDBStr = buffer.toString();
} catch (IOException e){
Log.e(LOG_TAG, "Error: ", e);
return null;
} finally {
if (urlConnection != null){
urlConnection.disconnect();
}
if (reader != null){
try{
reader.close();
} catch (final IOException e){
Log.e(LOG_TAG, "Error closing stream", e);
}
}
}
try {
return getFilmDataFromJson(movieDBStr);
} catch (JSONException e){
Log.e(LOG_TAG, e.getMessage(), e);
e.printStackTrace();
}
return null;
}
/**
* Take the String representing the complete forecast in JSON Format and
* pull out the data we need to construct the Strings needed for the wireframes.
*
* Fortunately parsing is easy: constructor takes the JSON string and converts it
* into an Object hierarchy for us.
*/
private FilmParcelable[] getFilmDataFromJson(String movieDBStr)
throws JSONException {
// JSON objects that need to be extracted
final String MDB_RESULTS = "results";
final String MDB_ID = "id";
final String MDB_SYNOPSIS = "overview";
final String MDB_RELEASE = "release_date";
final String MDB_POSTER = "poster_path";
final String MDB_TITLE = "title";
final String MDB_RATING = "vote_average";
JSONObject filmJson = new JSONObject(movieDBStr);
JSONArray filmArray = filmJson.getJSONArray(MDB_RESULTS);
FilmParcelable[] resultFilms = new FilmParcelable[filmArray.length()];
for (int i = 0; i < filmArray.length(); i++){
// Data needed by the FilmParcelable
int id;
String title;
String releaseDate;
String posterUrl;
Double voteAverage;
String plotSynopsis;
JSONObject film = filmArray.getJSONObject(i);
id = film.getInt(MDB_ID);
plotSynopsis = film.getString(MDB_SYNOPSIS);
releaseDate = film.getString(MDB_RELEASE);
posterUrl = "http://image.tmdb.org/t/p/w300" + film.getString(MDB_POSTER);
title = film.getString(MDB_TITLE);
voteAverage = film.getDouble(MDB_RATING);
Log.d(LOG_TAG, title);
Log.d(LOG_TAG, posterUrl);
resultFilms[i] = new FilmParcelable(id, title, releaseDate, posterUrl, voteAverage, plotSynopsis);
}
return resultFilms;
}
#Override
protected void onPostExecute(FilmParcelable[] result){
if (result != null){
filmParcels = new ArrayList<>(Arrays.asList(result));
}
}
}
}
ImageAdaptor.java:
public class ImageAdaptor extends ArrayAdapter<FilmParcelable> {
public ImageAdaptor(Activity context, ArrayList<FilmParcelable> filmParcels){
super(context, 0, filmParcels);
}
public View getView(int position, View convertView, ViewGroup parent){
Context context= getContext();
View gridView;
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
String mUrl = getItem(position).getUrl();
if (convertView == null) {
gridView = inflater.inflate(R.layout.gridview_film_layout, parent, false);
// Find the image view from the gridview_film_layout
ImageView posterView = (ImageView) gridView.findViewById(R.id.grid_item_image);
// Set the image view to contain image located at mUrl
Picasso.with(getContext()).load(mUrl).into(posterView);
} else {
gridView = convertView;
}
return gridView;
}
}
accordingly to the code you posted you are returning over and over the same cell of your GridView. You should have those two lines
ImageView posterView = (ImageView) gridView.findViewById(R.id.grid_item_image);
Picasso.with(getContext()).load(mUrl).into(posterView);
out of the if/else guard:
if (convertView == null) {
// inflate
} else {
// gridView = convertView;
}
ImageView posterView = (ImageView) gridView.findViewById(R.id.grid_item_image);
Picasso.with(getContext()).load(mUrl).into(posterView);
return gridView;
I was attempting to update the adapter after populating the arraylist used for the adapter. However the arraylist was populated and updated in the background so the code:
updateFilms();
updateAdaptor();
was causing the adaptor to update before the data had completed loading in the background.
After fixing that Blackbelt's solution was correct.

SAX Parsing doesn't fill ListView

I'm sorry for my bad english firstly.
Here is my goal;
I need to read xml (actually from web service but there are some problem with my host and i use direct xml link, as my web services return data) from my link. Then i need to write those data to listView.
And here is my problem;
I read that xml from web link and i think parsed xml. I say like this because when i debug project i can see some data on my GettersSetters variable. But when i send those data to my adapter class, there is no action, i guess. Because i can not see any changes on my listView.
Here is my MainActivity.java
public class MainActivity extends Activity {
XMLGettersSetters data;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
try {
SAXParserFactory saxPF = SAXParserFactory.newInstance();
SAXParser saxP = saxPF.newSAXParser();
XMLReader xmlR = saxP.getXMLReader();
URL url = new URL("http://utkuyegen.com/dersProgramiListele.xml");
XMLHandler myXMLHandler = new XMLHandler();
xmlR.setContentHandler(myXMLHandler);
xmlR.parse(new InputSource(url.openStream()));
} catch (Exception e) {
Log.e("xmlParser", e.getMessage());
System.out.println(e);
}
data = XMLHandler.data;
System.out.println("data = XMLHandler.data");
try {
ListView lv = (ListView) findViewById(R.id.listView1);
System.out.println("listView tanımlandı");
dataAdapter adapter = new dataAdapter(this, R.layout.listview_row,
data.getDersID(), data.getDersAdi());
System.out.println("adapter tanımlandı");
lv.setAdapter(adapter);
System.out.println("adapter listView 'e atandı");
// TextView textView1 = (TextView) findViewById(R.id.textView1);
// textView1.setText(data.getDersID().get(2));
System.out.println("onCreate son satır");
} catch (Exception e) {
Log.d("tag", e.getMessage());
}
}
public class dataAdapter extends ArrayAdapter<XMLGettersSetters> {
// XMLGettersSetters items;
ArrayList<String> _dID, _dAdi;
public dataAdapter(Context context, int textViewResourceId,
ArrayList<String> dID, ArrayList<String> dAdi) {
super(context, textViewResourceId);
this._dID = dID;
this._dAdi = dAdi;
Log.d("da", "1");
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
if (convertView == null) {
LayoutInflater vi = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = vi.inflate(R.layout.listview_row, null);
Log.d("da", "5");
}
Log.d("da", "2");
TextView dersID = (TextView) convertView.findViewById(R.id.dersID);
TextView dersAdi = (TextView) convertView
.findViewById(R.id.dersAdi);
Log.d("da", "3");
dersID.setText(_dID.get(position));
dersAdi.setText(_dAdi.get(position));
Log.d("da", "4");
return convertView;
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
And XMLGettersSetters.java
public class XMLGettersSetters {
private ArrayList<String> dersID = new ArrayList<String>();
private ArrayList<String> dersAdi = new ArrayList<String>();
public XMLGettersSetters(ArrayList<String> dersID, ArrayList<String> dersAdi) {
this.dersID = dersID;
this.dersAdi = dersAdi;
}
public XMLGettersSetters() {
}
public String getDersID_tek(int i) {
return dersID.get(i);
}
public ArrayList<String> getDersID() {
return dersID;
}
public void setDersID(String dersID) {
this.dersID.add(dersID);
}
public String getDersAdi_tek(int i) {
return dersAdi.get(i);
}
public ArrayList<String> getDersAdi() {
return dersAdi;
}
public void setDersAdi(String dersAdi) {
this.dersAdi.add(dersAdi);
}
}
And XMLHandler.java
public class XMLHandler extends DefaultHandler {
String elementValue = null;
Boolean elementOn = false;
public static XMLGettersSetters data = null;
public static XMLGettersSetters getXMLData() {
return data;
}
public static void setXMLData(XMLGettersSetters data) {
XMLHandler.data = data;
}
#Override
public void startElement(String uri, String localName, String qName,
Attributes attributes) throws SAXException {
elementOn = true;
if (localName.equals("ArrayOfDersProgrami"))
{
data = new XMLGettersSetters();
} else if (localName.equals("dersProgrami"))
{
/**
* We can get the values of attributes for eg. if the CD tag had an attribute( <CD attr= "band">Akon</CD> )
* we can get the value "band". Below is an example of how to achieve this.
*
* String attributeValue = attributes.getValue("attr");
* data.setAttribute(attributeValue);
*
* */
}
}
#Override
public void endElement(String uri, String localName, String qName)
throws SAXException {
elementOn = false;
/**
* Sets the values after retrieving the values from the XML tags
* */
if (localName.equalsIgnoreCase("DersID"))
data.setDersID(elementValue);
if (localName.equalsIgnoreCase("DersAdi"))
data.setDersAdi(elementValue);
}
#Override
public void characters(char[] ch, int start, int length)
throws SAXException {
if (elementOn) {
elementValue = new String(ch, start, length);
elementOn = false;
}
}
}
BTW, i got some point with my code and debug.
When i debug this codes, i see that i can not understand data.
This is my xml file
<?xml version="1.0" encoding="utf-8"?>
<ArrayOfDersProgrami xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://tempuri.org/">
<dersProgrami>
<DersID>0</DersID>
<DersAdi>0</DersAdi>
</dersProgrami>
<dersProgrami>
<DersID>1</DersID>
<DersAdi>1</DersAdi>
</dersProgrami>
<dersProgrami>
<DersID>2</DersID>
<DersAdi>4</DersAdi>
</dersProgrami>
<dersProgrami>
<DersID>3</DersID>
<DersAdi>9</DersAdi>
</dersProgrami>
<dersProgrami>
<DersID>4</DersID>
<DersAdi>16</DersAdi>
</dersProgrami>
</ArrayOfDersProgrami>
As you see there is five data but as i said when i debug i see 12 data in my array.
I scope data variable "data = XMLHandler.data;" and i see two arrayList, dersAdi and dersID. Then i scope dersAdi, i see array = Object[12], modCount = 5, size = 5. Then i scope array = Obj.. i see [0, 1, 4, 9, 16, null, null, null, null, null, null, null].
What is that mean? I got 5 datas in my xml but there is 12 datas.
And What i want;
I need some suggestion and i'm close to deadline.
This project is my season
It’s a normal behavior I think, you are debugging an ArrayList<> so what you see are the variables into the class ArrayList as you can see there is an array into that initially has size 12 and null cells and also there is an integer that holds the real number of your items (modCount)
so don’t worry about that the class ArrayList is well developed :P
to get sure from what I say you can debug any other ArrayList you will get same behavior.
EDIT:
try to call adapter.notifyDataSetChanged();after setting your adapter to listview

ListView displaying incorrect title

I have a simple application that pulls an XML file from pc worlds RSS feed here:
http://feeds.pcworld.com/pcworld/latestnews
I want to display the name of the titles in a ListView then when the user selects one the article opens up in a browser window.
The application is working the only thing is that the title is not being displayed correctly in the ListView.
It should be something like this:
Make you website stand out with Windows 8
But instead it is this:
com.example.simplerss.Item#424b9998
Any ideas?
This is my code for the MainActivity
public class MainActivity extends ListActivity {
ArrayAdapter<Item> adapter;
List<Item>items;//Holds item objects containing info relating to element pulled from XML file.
Item item;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//initialize variables
items = new ArrayList<Item>();
new PostTask().execute();
adapter= new ArrayAdapter<Item>(this, android.R.layout.simple_list_item_1, items);
setListAdapter(adapter);
}
private InputStream getInputStream(URL url) {
try{
return url.openConnection().getInputStream();
}catch(IOException e){
return null;
}
}
#Override
protected void onListItemClick(ListView l, View v, int position, long id) {
Uri uri = items.get(position).getLink();
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
//ASYNC CLASS
private class PostTask extends AsyncTask<String, Integer, String>{
#Override
protected String doInBackground(String... arg0) {
try{
//link to data source
URL url = new URL("http://feeds.pcworld.com/pcworld/latestnews");
//Set up parser
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
factory.setNamespaceAware(false);
XmlPullParser xpp = factory.newPullParser();
//get XML from input stream
InputStream in = getInputStream(url);
if (in == null) {
throw new Exception("Empty inputstream");
}
xpp.setInput(in, "UTF_8");
//Keep track of which tag inside of XML
boolean insideItem = false;
//Loop through the XML file and extract data required
int eventType = xpp.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT) {
if (eventType == XmlPullParser.START_TAG) {
Log.v("ENTER", String.valueOf(xpp.getEventType()));
if (xpp.getName().equalsIgnoreCase("item")) {
insideItem = true;
//Create new item object
item = new Item();
} else if (xpp.getName().equalsIgnoreCase("title")) {
if (insideItem){
item.setTitle(xpp.nextText());
Log.i("title", item.getTitle());
}
}
else if (xpp.getName().equalsIgnoreCase("description")) {
if (insideItem){
item.setDescription(xpp.nextText());
}
}
else if (xpp.getName().equalsIgnoreCase("link")) {
if (insideItem){
item.setLink(Uri.parse(xpp.nextText()));
}
}
}else if(eventType==XmlPullParser.END_TAG && xpp.getName().equalsIgnoreCase("item")){
insideItem=false;
//add item to list
items.add(item);
}
eventType = xpp.next(); //move to next element
publishProgress();
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (XmlPullParserException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
catch (Exception e) {
e.printStackTrace();
}
return "COMPLETED";
}
#Override
protected void onProgressUpdate(Integer... values) {
adapter.notifyDataSetChanged();
}
public void onPostExecute(String s) {
Toast.makeText(getApplicationContext(), s + " Items: " + items.size(), Toast.LENGTH_SHORT).show();
adapter.notifyDataSetChanged();
}
}
}
and for the Item Class
public class Item {
//Variables
private String title;
private Uri link;
private String description;
public Item() {
super();
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public Uri getLink() {
return link;
}
public void setLink(Uri link) {
this.link = link;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
}
Override the toString() method in Item.
#Override
public String toString() {
return title;
}
This should solve your problem.
Right now, the ArrayAdapter sets its View's texts to Item.toString(), but this is the default method of Object that returns the Object's ID. With overriding it, you give it a meaningful value, in your case the title.
I think the problem lies in:
else if (xpp.getName().equalsIgnoreCase("title")) {
if (insideItem){
item.setTitle(xpp.nextText());
Log.i("title", item.getTitle());
}
}
Here, getName() is a method from the Java Class object. The method you want is readContent() I think. I haven't used this library so that may not be exactly correct but you can certainly find what you need in the docs.

Converting single-thread app to ASyncTask app

I am creating a simple RSS reader which displays headlines in ListView, downloading it from the .xml file of specified website.
I wrote the app and it works on the single thread, but i want to use ASyncTask so that all the downloading happens in the background and the UI don't hang.
Now, i have never used AsyncTask before, and i googled it but still i'm not sure where to transfer the methods of my code to which ASyncTask methods. Please help me do it.
SimpleRssReaderActivity.java
package mohit.app.rssreader;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;
import android.app.ListActivity;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
public class SimpleRssReaderActivity extends ListActivity {
List headlines;
List links;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Initializing instance variables arrays
headlines = new ArrayList();
links = new ArrayList();
try {
URL url = new URL("http://feeds.pcworld.com/pcworld/latestnews");
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
factory.setNamespaceAware(false);
XmlPullParser xpp = factory.newPullParser();
// get the XML from an input stream
xpp.setInput(getInputStream(url), "UTF_8");
boolean insideItem = false;
// Returns the type of current event: START_TAG, END_TAG, etc..
int eventType = xpp.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT)
{
if (eventType == XmlPullParser.START_TAG)
{
if (xpp.getName().equalsIgnoreCase("item"))
{
insideItem = true;
}
else if (xpp.getName().equalsIgnoreCase("title"))
{
if (insideItem)
headlines.add(xpp.nextText()); //extract the headline
}
else if (xpp.getName().equalsIgnoreCase("link"))
{
if (insideItem)
links.add(xpp.nextText()); //extract the link of article
}
}
else if(eventType==XmlPullParser.END_TAG && xpp.getName().equalsIgnoreCase("item"))
{
insideItem=false;
}
eventType = xpp.next(); //move to next element
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (XmlPullParserException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
// Binding data
ArrayAdapter adapter = new ArrayAdapter(this,
android.R.layout.simple_list_item_1, headlines);
setListAdapter(adapter);
}
public InputStream getInputStream(URL url) {
try {
return url.openConnection().getInputStream();
} catch (IOException e) {
return null;
}
}
#Override
protected void onListItemClick(ListView l, View v, int position, long id) {
Uri uri = Uri.parse((String) links.get(position));
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
}
}
SO thats my whole code, tell me which new methods to create and the codes to transfer in that method. THNX!
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
InitTask _initTask = new InitTask();
_initTask.execute( this );
}
some thing like this ......
/**
* sub-class of AsyncTask
*/
protected class InitTask extends AsyncTask<Context, Integer, ArrayList>
{
// -- run intensive processes here
// -- notice that the datatype of the first param in the class definition matches the param passed to this method
// -- and that the datatype of the last param in the class definition matches the return type of this method
#Override
protected String doInBackground( Context... params )
{
return inBackground();
}
// -- gets called just before thread begins
#Override
protected void onPreExecute()
{
Log.i( "makemachine", "onPreExecute()" );
super.onPreExecute();
}
// -- called from the publish progress
// -- notice that the datatype of the second param gets passed to this method
#Override
protected void onProgressUpdate(Integer... values)
{
super.onProgressUpdate(values);
Log.i( "makemachine", "onProgressUpdate(): " + String.valueOf( values[0] ) );
}
// -- called if the cancel button is pressed
#Override
protected void onCancelled()
{
super.onCancelled();
Log.i( "makemachine", "onCancelled()" );
}
// -- called as soon as doInBackground method completes
// -- notice that the third param gets passed to this method
#Override
protected void onPostExecute( ArrayList result )
{
super.onPostExecute(result);
Log.i( "makemachine", "onPostExecute(): " + result );
// Binding data
ArrayAdapter adapter = new ArrayAdapter(this,
android.R.layout.simple_list_item_1, result );
SimpleRssReaderActivity.this.setListAdapter(adapter);
}
}
private ArrayList inBackground(){
// Initializing instance variables arrays
headlines = new ArrayList();
links = new ArrayList();
try {
URL url = new URL("http://feeds.pcworld.com/pcworld/latestnews");
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
factory.setNamespaceAware(false);
XmlPullParser xpp = factory.newPullParser();
// get the XML from an input stream
xpp.setInput(getInputStream(url), "UTF_8");
boolean insideItem = false;
// Returns the type of current event: START_TAG, END_TAG, etc..
int eventType = xpp.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT)
{
if (eventType == XmlPullParser.START_TAG)
{
if (xpp.getName().equalsIgnoreCase("item"))
{
insideItem = true;
}
else if (xpp.getName().equalsIgnoreCase("title"))
{
if (insideItem)
headlines.add(xpp.nextText()); //extract the headline
}
else if (xpp.getName().equalsIgnoreCase("link"))
{
if (insideItem)
links.add(xpp.nextText()); //extract the link of article
}
}
else if(eventType==XmlPullParser.END_TAG && xpp.getName().equalsIgnoreCase("item"))
{
insideItem=false;
}
eventType = xpp.next(); //move to next element
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (XmlPullParserException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return headlines ;
}
this example is as per your code but if possible i would like to give some suggestion not must but should use
1- creating and setting the adapter work should remain in Oncreate just set the empty Array list there and pass that list to Asytask (in constructor ) and fill the data in same and just call in notify data set changed in onPostExecute.
Well I don't really know what methods you want to do in the async task, but basically you use this model here
public class PostTask extends AsyncTask<Void/*what the doInBackground method wants*/, String/* What the onProgress method wants*/, Boolean /*What the doInBackground method returns*/> {
#Override
protected Boolean doInBackground(Void... params) {
boolean result = false;
//All your code goes in here
//If you want to do something on the UI use progress update
publishProgress("progress");
return result;
}
protected void onProgressUpdate(String... progress) {
StringBuilder str = new StringBuilder();
for (int i = 1; i < progress.length; i++) {
str.append(progress[i] + " ");
}
}
}
You want to do all your networking tasks in an async task :D
Everything goes in doInBackground except the part where you update the UI by creating the adapter and setting it. That goes in onPostExecute.
For each application in android there is one main thread called UI thread. And if you do all the time taking tasks in the UI thread your application may not respond well and it leads to force close some time. To avoid this kind of problems you have to use Async Task.
I reccomend you to go through Process&Threads where they have explained how to handle time taking tasks in back ground. You have to subclass AsyncTask and and implement the doInBackground() callback method to do long tasks.
Create a class for your Asynch task
EXAMPLE: MyActivity.java =>
public class MyActivity extends MyBaseActivity {
...
MyDownloaderTask downloaderTask = null;
...
public void onCreate (Bundl savedInstanceState) {
...
downloaderTask = new MyDownloaderTask ();
...
}
}
private class MyDownloaderTask extends AsyncTask<Object, String, Boolean> {
...
#Override
protected void onPreExecute () {
...
Move your XML methods into your new "downloader" class as appropriate.
My guess is you'll just cut/paste everything into an override of "doInBackground()"
Here's a good tutorial:
http://www.vogella.com/articles/AndroidPerformance/article.html
<= Look down to "5. Tutorial: AsyncTask"
'Hope that helps

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