Develop Reference

ListView populates but each view is blank at first?

I'm using a ListView inside a Fragment which downloads notes from Firebase storage and then displays them. However, the problem I'm running into is when it displays the notes its just a empty note layout, but when I switch activities and go back they're no longer blank, they're loaded. I'm not sure where exactly I'm going wrong, I've tried calling onDataSetChange to the Adapter Everywhere, also tried invalidate() and invalidateViews() on the ListView hoping it would just simply refresh the views, but unfortunately that didnt work either :/ the code is below, thank you in advanced for any help! :)
this is where I'm setting the Adapter in my Notes fragment
mNoteStorage = FirebaseStorage.getInstance().getReference().child("Notes").child(currentUser.getUid());
mNotesDatabase.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
my_notes.setAdapter(null);
Iterable<DataSnapshot> all_keys = dataSnapshot.getChildren();
filename_arrayList = new ArrayList<>();
na = null;
for (DataSnapshot each_key : all_keys) {
String each = each_key.getKey();
filename_arrayList.add(each);
}
for (String each_filename : filename_arrayList) {
downloadFile(each_filename);
Note each_note = Utilities.getNoteByName(getContext(), each_filename + Utilities.FileExtention);
each_note_array.add(each_note);
}
if (each_note_array == null || each_note_array.size() == 0) {
Toast.makeText(getActivity().getApplicationContext(), "No Notes!", Toast.LENGTH_LONG).show();
} else {
na = new MyNotesAdapter(getContext(), R.layout.item_note, each_note_array);
my_notes.setAdapter(na);
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
and Here's my Adapter
class MyNotesAdapter extends ArrayAdapter<Note> {
Context ctx;
public MyNotesAdapter(#NonNull Context context, int resource, ArrayList<Note> note) {
super(context, resource, note);
this.ctx = context;
}
#NonNull
#Override
public View getView(int position, #Nullable View convertView, #NonNull ViewGroup parent) {
//return super.getView(position, convertView, parent);
if (convertView == null) {
convertView = LayoutInflater.from(getContext()).inflate(R.layout.item_note, null);
}
Note note = getItem(position);
if(note != null) {
TextView title = (TextView) convertView.findViewById(R.id.list_note_title);
TextView content = (TextView) convertView.findViewById(R.id.list_note_content);
TextView date = (TextView) convertView.findViewById(R.id.list_note_date);
Typeface music_font = Typeface.createFromAsset(getContext().getAssets(), "fonts/melodymakernotesonly.ttf");
Typeface scribble_card = Typeface.createFromAsset(getContext().getAssets(), "fonts/the unseen.ttf");
if (getThemeCountInt() == 0) {
title.setTypeface(music_font);
} else if (getThemeCountInt() == 1) {
title.setTypeface(scribble_card);
}
content.setTypeface(scribble_card);
title.setText(note.getTitle());
date.setText(note.getDateTimeFormatted(getContext()));
if(note.getContent().length() > 25) {
content.setText(note.getContent().substring(0,25) + "...");
} else {
content.setText(note.getContent());
}
if(note.getContent().length() <= 0) {
content.setText("(Empty Note..)");
} else {
content.setText(note.getContent());
}
if (note.getTitle().length() <= 0) {
title.setText("(Untitled)");
} else {
title.setText(note.getTitle());
}
}
return convertView;
}
private int getThemeCountInt() {
SharedPreferences mSharedPreferences = this.getContext().getSharedPreferences("theme", MODE_PRIVATE);
int selectedTheme = mSharedPreferences.getInt("theme", 0);
return selectedTheme;
}
}
downloadFile
private void downloadFile(final String filenames) {
final String each_filename = filenames + Utilities.FileExtention;
final long file_size = 1024 * 1024;
mNoteStorage.child(each_filename).getBytes(file_size).addOnSuccessListener(new OnSuccessListener<byte[]>() {
#Override
public void onSuccess(byte[] bytes) {
FileOutputStream stream;
FileInputStream streamIn;
try {
File dir = getActivity().getApplication().getFilesDir();
File file = new File(dir, each_filename);
stream = new FileOutputStream(file);
stream.write(bytes);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
Utilities.getNoteByName
public static Note getNoteByName(Context context, String filename) {
File file = new File(context.getFilesDir(), filename);
Note note;
if (file.exists()) {
FileInputStream fis;
ObjectInputStream ois;
try {
fis = context.openFileInput(filename);
ois = new ObjectInputStream(fis);
note = (Note) ois.readObject();
fis.close();
ois.close();
} catch (IOException | ClassNotFoundException e) {
e.printStackTrace();
return null;
}
return note;
}
return null;
}

After you create MyNotesAdapter call notifyDataSetChanged() method to let ListView instance knows that underlying data has changed.
my_notes.setAdapter(na);
na.notifyDataSetChanged();
Personally I prefer to create and set adapter instance once and then use its add() method to manipulate its underlying data. Once I finished, I call adapter notifyDataSetChanged().
Recreating new adapter instance each time database change may trigger garbage collector to run more often.

Android Listview Scroll position

I have a ListView and a list view adapter. The adapter populates the ListView from a List. The list view has a onScrollListener. The problem I have is when on scroll new data are loaded to the view but the scroll bar jumps to the top of the view.
What I want is to keep the scroll position where it was!
Any help?
Thanks
List View class:
private class GetItems extends AsyncTask<Void, Void, Void>
{
#Override
protected void onPreExecute() {
super.onPreExecute();
// Create a progressdialog
mProgressDialog = new ProgressDialog(AppList.this);
// Set progressdialog title
mProgressDialog.setTitle("Loading more");
mProgressDialog.setMessage("loading);
mProgressDialog.setIndeterminate(false);
// Show progressdialog
mProgressDialog.show();
}
#Override
protected Void doInBackground(Void... params)
{
applicationList = new ArrayList();
try
{
GetDataAppList getDataAppList = new GetDataAppList();
JSONArray jsonData = getDataAppList.getJSONData(webfileName, limit, offset);
for (int i = 0; i <= jsonData.length() - 2; i++)
{
JSONObject c = jsonData.getJSONObject(i);
id = c.getString("id");
name = c.getString("name");
logo = c.getString("logo");
developer = c.getString("developer");
rate = c.getInt("rates");
category = c.getInt("category");
fileName = c.getString("filename");
path = c.getString("path");
appSize = c.getDouble("size");
if(category == 1001)
{
String gCat = c.getString("game_category");
applicationList.add(new ApplicationPojo(id,name,logo,developer,appSize,category,fileName,path,gCat));
}
else
{
applicationList.add(new ApplicationPojo(id,name,logo,developer,appSize,category,fileName,path));
}
}
JSONObject sizeObj = jsonData.getJSONObject(jsonData.length() - 1);
size = sizeObj.getInt("size");
}
catch (Exception ex)
{
Log.d("Thread:", ex.toString());
}
return null;
}
#Override
protected void onPostExecute(Void result)
{
// Locate the ListView in listview.xml
listview = (ListView) findViewById(R.id.listView);
// Pass the results into ListViewAdapter.java
adapter = new ListViewAdapter(AppList.this, applicationList,listview);
// Binds the Adapter to the ListView
listview.setAdapter(adapter);
// Close the progressdialog
mProgressDialog.dismiss();
// Create an OnScrollListener
listview.setOnScrollListener(new OnScrollListener() {
#Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
int threshold = 1;
int count = listview.getCount();
if (scrollState == SCROLL_STATE_IDLE) {
if (listview.getLastVisiblePosition() >= count - threshold) {
if (size >= offset)
{
new LoadMoreDataTask().execute();
offset = offset + 15;
}
else
{
Toast.makeText(getApplicationContext(), "ختم لست!", Toast.LENGTH_LONG).show();
}
}
}
}
#Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
// TODO Auto-generated method stub
}
});
RatingBar bar = (RatingBar) findViewById(R.id.ratingBarShow);
}
}
private class LoadMoreDataTask extends AsyncTask<Void, Void, Void> {
#Override
protected void onPreExecute() {
super.onPreExecute();
mProgressDialog = new ProgressDialog(AppList.this);
mProgressDialog.setTitle("Loading more");
mProgressDialog.setMessage("loading);
mProgressDialog.setIndeterminate(false);
mProgressDialog.show();
}
#Override
protected Void doInBackground(Void... params)
{
try
{
GetDataAppList getDataAppList = new GetDataAppList();
JSONArray jsonData = getDataAppList.getJSONData(webfileName, limit, offset);
for (int i = 0; i <= jsonData.length(); i++) {
JSONObject c = jsonData.getJSONObject(i);
id = c.getString("id");
name = c.getString("name");
logo = c.getString("logo");
developer = c.getString("developer");
rate = c.getInt("rates");
category = c.getInt("category");
fileName = c.getString("filename");
path = c.getString("path");
appSize = c.getDouble("size");
if(category == 1001)
{
String gCat = c.getString("game_category");
applicationList.add(new ApplicationPojo(id,name,logo,developer,appSize,category,fileName,path,gCat));
}
else
{
applicationList.add(new ApplicationPojo(id,name,logo,developer,appSize,category,fileName,path));
}
}
}
catch (Exception ex)
{
}
return null;
}
#Override
protected void onPostExecute(Void result)
{
int position = listview.getLastVisiblePosition();
adapter = new ListViewAdapter(AppList.this, applicationList,listview);
listview.setAdapter(adapter);
listview.setSelectionFromTop(position, 0);
mProgressDialog.dismiss();
}
}
The Adpater class:
public ListViewAdapter(Activity activity, ArrayList<ApplicationPojo> applicationList, ListView listView)
{
this.activity = activity;
this.applicationList = applicationList;
this.inflater = LayoutInflater.from(activity);
downloader = new ApkFileDownloader(activity);
this.listView = listView;
}
#Override
public int getCount() {
return applicationList.size();
}
#Override
public ApplicationPojo getItem(int position) {
return applicationList.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
public View getView(final int position, View view, ViewGroup parent)
{
if (view == null)
{
holder = new ViewHolder();
view = inflater.inflate(R.layout.singleapp, null);
holder.openInstalledAppBtn = (ImageView) view.findViewById(R.id.openInstalledApp);
holder.downloadBtn = (ImageView) view.findViewById(R.id.updateApp);
holder.progressBar = (ProgressBar)view.findViewById(R.id.updateProgress);
holder.cancelBtn = (ImageView) view.findViewById(R.id.cancel);
holder.appName = (TextView) view.findViewById(R.id.appName);
holder.developer = (TextView) view.findViewById(R.id.developer);
holder.size = (TextView) view.findViewById(R.id.size);
holder.appCat = (TextView) view.findViewById((R.id.appCat));
holder.installBtn = (ImageView) view.findViewById(R.id.install);
holder.catlogo = (ImageView) view.findViewById(R.id.catlogo);
view.setTag(holder);
}
else
{
holder = (ViewHolder) view.getTag();
}
try
{
final View finalView = view;
holder.logo = (ImageView) finalView.findViewById(R.id.appLogo);
logoName = applicationList.get(position).getLogo();
Picasso.with(activity)
.load(IPClass.SERVERIP + logoName)
.into(holder.logo);
// holder.logo.setOnClickListener(new View.OnClickListener() {
// #Override
// public void onClick(View arg0) {
//
// }
// });
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String appid = applicationList.get(position).getId();
int category = applicationList.get(position).getCategory();
Intent rec1Intent = new Intent(activity, AppView.class);
activity.startActivity(rec1Intent);
AppView appView = new AppView();
appView.setParameters(appid, category);
AppList.adapter.notifyDataSetChanged();
}
});
final String id = applicationList.get(position).getId();
final String path = applicationList.get(position).getPath();
final String fileName = applicationList.get(position).getFileName();
final String name = applicationList.get(position).getName();
final String developer = applicationList.get(position).getDeveloper();
final double size = applicationList.get(position).getSize();
final String logo = applicationList.get(position).getLogo();
final int category = applicationList.get(position).getCategory();
final String appName = applicationList.get(position).getFileName();
String checkAppInstalled = appName.substring(0,appName.length() - 4);
//------------CHECK IF APPLICATION IS INSTALLED ----------------------------------------
if(appInstalled(checkAppInstalled))
{
holder.downloadBtn.setVisibility(View.GONE);
holder.cancelBtn.setVisibility(View.GONE);
holder.progressBar.setVisibility(View.GONE);
holder.installBtn.setVisibility(View.GONE);
holder.openInstalledAppBtn.setVisibility(View.VISIBLE);
holder.openInstalledAppBtn.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v) {
String fileName = (applicationList.get(position).getFileName());
String appToOpen = fileName.substring(0,fileName.length() - 4);
Context ctx = activity.getApplicationContext();
Intent mIntent = ctx.getPackageManager().getLaunchIntentForPackage(appToOpen);
String mainActivity = mIntent.getComponent().getClassName();
Intent intent = new Intent("android.intent.category.LAUNCHER");
intent.setClassName(appToOpen, mainActivity);
activity.startActivity(intent);
}
});
}
//------------- IF APPLICATION IS NOT ALREADY INSTALLED --------------------------------
else
{
//------------------------ CHECK IF APK EXISTS -------------------------------------
String filePath = Environment.getExternalStorageDirectory().toString();
File file = new File(filePath + "/appsaraai/" + fileName);
if(file.exists())
{
holder.downloadBtn.setVisibility(View.GONE);
holder.cancelBtn.setVisibility(View.GONE);
holder.openInstalledAppBtn.setVisibility(View.GONE);
holder.progressBar.setVisibility(View.GONE);
holder.installBtn.setVisibility(View.VISIBLE);
holder.installBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(new File(Environment.getExternalStorageDirectory() + "/appsaraai/" + fileName)), "application/vnd.android.package-archive");
activity.startActivity(intent);
for (int i = 0; i < DownloadLists.list.size(); i++) {
if (DownloadLists.list.get(i).getName().equals(name)) {
DownloadLists.list.remove(i);
}
}
}
});
AppList.adapter.notifyDataSetChanged();
}
//------------------ IF APK DOES NOT EXIST -----------------------------------------
else
{
//-----CHECK IF DOWNLOAD IS IN PROGRESS ----------------------------------------
if (ApkFileDownloader.applicationList.containsKey(name))
{
holder.downloadBtn.setVisibility(View.GONE);
holder.installBtn.setVisibility(View.GONE);
holder.openInstalledAppBtn.setVisibility(View.GONE);
new ApkFileDownloader(activity).getDownloadStatus(holder.progressBar, name, holder.installBtn, holder.cancelBtn);
holder.progressBar.setVisibility(View.VISIBLE);
holder.cancelBtn.setVisibility(View.VISIBLE);
holder.cancelBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
downloader.cancelDownload(name);
holder.cancelBtn.setVisibility(View.GONE);
holder.downloadBtn.setVisibility(View.VISIBLE);
DownloadLists dlist = new DownloadLists(activity);
dlist.deleteData(name);
try {
AppList.adapter.notifyDataSetChanged();
} catch (Exception ex) {
System.out.println(ex);
}
try
{
SearchResult.adapter.notifyDataSetChanged();
}
catch (Exception ex)
{
System.out.println(ex);
}
}
});
}
//-------------- IF DOWNLOAD IS NOT IN PROGRESS START NEW DOWNLOAD -------------
else
{
holder.progressBar.setVisibility(View.GONE);
holder.cancelBtn.setVisibility(View.GONE);
holder.installBtn.setVisibility(View.GONE);
holder.openInstalledAppBtn.setVisibility(View.GONE);
holder.downloadBtn.setVisibility(view.VISIBLE);
holder.downloadBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
holder.downloadBtn.setVisibility(View.GONE);
holder.cancelBtn.setVisibility(View.VISIBLE);
holder.cancelBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
downloader.cancelDownload(name);
holder.cancelBtn.setVisibility(View.GONE);
holder.downloadBtn.setVisibility(View.VISIBLE);
try {
AppList.adapter.notifyDataSetChanged();
} catch (Exception ex) {
System.out.println(ex);
}
try {
SearchResult.adapter.notifyDataSetChanged();
} catch (Exception ex) {
System.out.println(ex);
}
}
});
new Thread(new Runnable() {
#Override
public void run() {
try {
Bitmap logoImg = Picasso.with(activity).load(IPClass.SERVERIP + logo).get();
DownloadLists.list.add(new ApplicationPojo(id, name, developer, size, logoImg, holder.progressBar));
DownloadLists dlist = new DownloadLists(activity);
dlist.insertData(id, name, developer, size, fileName, logoImg);
UpdateServerDownload d = new UpdateServerDownload();
d.updateDownloadNo(id, category);
} catch (IOException e) {
e.printStackTrace();
}
}
}).start();
new ApkFileDownloader(activity).setParameters(path, fileName, name);
try {
AppList.adapter.notifyDataSetChanged();
} catch (Exception ex) {
System.out.println(ex);
}
try {
SearchResult.adapter.notifyDataSetChanged();
} catch (Exception ex) {
System.out.println(ex);
}
}
});
}
}
}
holder.appName.setText(applicationList.get(position).getName());
holder.developer.setText(applicationList.get(position).getDeveloper());
String sizeText = " میگابایت ";
String appSize =String.valueOf(applicationList.get(position).getSize()) + sizeText;
holder.size.setText(appSize);
if(category == 1001)
{
String cat = applicationList.get(position).getgCat();
holder.appCat.setText(" " + returnGameCat(cat));
holder.catlogo.setImageResource(R.drawable.gamecatlogo);
}
}
catch (Exception ex)
{
Log.d("Adapter Exception", ex.toString());
}
return view;
}
//--------------- A METHOD TO CHECK IF APPLICATION IS ALREADY INSTALLED ------------------------
public boolean appInstalled(String checkApp)
{
pm = activity.getPackageManager();
try
{
pm.getPackageInfo(checkApp, PackageManager.GET_ACTIVITIES);
isAppInstalled = true;
}
catch (PackageManager.NameNotFoundException e)
{
isAppInstalled = false;
}
return isAppInstalled;
}

You are doing wrong in your GetItems and LoadMoreDataTask AsyncTask. you are setting new adapter each time when you scroll down so when new data are loaded to the view the scroll bar jumps to the top of the view.
You need to call
adapter = new ListViewAdapter(AppList.this, applicationList,listview);
listview.setAdapter(adapter);
only first time then you have to only call
adapter.notifyDataSetChanged()
to update your ListView no need to set adapter each time when making new request and also you have to set OnScrollListener to ListView only one time currently new OnScrollListener is set each time when making new request.

You need to setAdapter first time when adapter is null or you are fetching data first time after it just call notifyDataSetChanged()

Save state of listview before updating and then restore:
// save index and top position
int index = mListView.getFirstVisiblePosition();
View v = mListView.getChildAt(0);
int top = (v == null) ? 0 : v.getTop();
// notify dataset changed or re-assign adapter here
// restore the position of listview
mListView.setSelectionFromTop(index, top);

The most Optimal Solution will be
// Save the ListView state (= includes scroll position) as a Parceble
Parcelable state = listView.onSaveInstanceState();
// e.g. set new items
listView.setAdapter(adapter);
// Restore previous state (including selected item index and scroll position)
listView.onRestoreInstanceState(state);
Reference : Retain Scroll Position Android ListView

List ImageView repeating same image when shared

I have a listView that is supposed to accept a shared message and image where the image is placed within the ImageView. This feature works for just the first message, but once an image is shared, each message received after that initial one becomes a copy of that same image even though the blank image placeholder was already set, which is just a one pixel black png:
holder.sharedSpecial.setImageResource(R.drawable.image_share_empty_holder);
An example is below:
The green textbox is the recipient. They have recieved a shared image from the yellow textbox. The yellow textbox then simply sends a normal message and I have set another image as a placeholder for normal messages: holder.sharedSpecial.setImageResource(R.drawable.image_share_empty_holder);
The same previously shared image takes precedence. I have used notifyDataSetChanged() so as to allow for the updating the adapter so that it would recognize not to use the same image, but to no avail.
How can I reformulate this class so that the image shared is only displayed with the proper message and not copied into each subsequent message?
The ArrayAdapter class:
public class DiscussArrayAdapter extends ArrayAdapter<OneComment> {
class ViewHolder {
TextView countryName;
ImageView sharedSpecial;
LinearLayout wrapper;
}
private TextView countryName;
private ImageView sharedSpecial;
private MapView locationMap;
private GoogleMap map;
private List<OneComment> countries = new ArrayList<OneComment>();
private LinearLayout wrapper;
private JSONObject resultObject;
private JSONObject imageObject;
String getSharedSpecialURL = null;
String getSharedSpecialWithLocationURL = null;
String specialsActionURL = "http://" + Global.getIpAddress()
+ ":3000/getSharedSpecial/";
String specialsLocationActionURL = "http://" + Global.getIpAddress()
+ ":3000/getSharedSpecialWithLocation/";
String JSON = ".json";
#Override
public void add(OneComment object) {
countries.add(object);
super.add(object);
}
public DiscussArrayAdapter(Context context, int textViewResourceId) {
super(context, textViewResourceId);
}
public int getCount() {
return this.countries.size();
}
private OneComment comment = null;
public OneComment getItem(int index) {
return this.countries.get(index);
}
public View getView(int position, View convertView, ViewGroup parent) {
final ViewHolder holder;
View row = convertView;
if (row == null) {
LayoutInflater inflater = (LayoutInflater) this.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = inflater.inflate(R.layout.message_list_item, parent, false);
holder = new ViewHolder();
holder.wrapper = (LinearLayout) row.findViewById(R.id.wrapper);
holder.countryName = (TextView) row.findViewById(R.id.comment);
holder.sharedSpecial = (ImageView) row.findViewById(R.id.sharedSpecial);
// Store the ViewHolder as a tag.
row.setTag(holder);
} else {
holder = (ViewHolder) row.getTag();
}
Log.v("COMMENTING","Comment is " + countries.get(position).comment);
//OneComment comment = getItem(position);
holder.countryName.setText(countries.get(position).comment);
// Initiating Volley
final RequestQueue requestQueue = VolleySingleton.getsInstance().getRequestQueue();
// Check if message has campaign or campaign/location attached
if (countries.get(position).campaign_id == "0" && countries.get(position).location_id == "0") {
holder.sharedSpecial.setImageResource(R.drawable.image_share_empty_holder);
Log.v("TESTING", "It is working");
} else if (countries.get(position).campaign_id != "0" && countries.get(position).location_id != "0") {
// If both were shared
getSharedSpecialWithLocationURL = specialsLocationActionURL + countries.get(position).campaign_id + "/" + countries.get(position).location_id + JSON;
// Test Campaign id = 41
// Location id = 104
// GET JSON data and parse
JsonObjectRequest getCampaignLocationData = new JsonObjectRequest(Request.Method.GET, getSharedSpecialWithLocationURL, null,
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
// Parse the JSON:
try {
resultObject = response.getJSONObject("shared");
} catch (JSONException e) {
e.printStackTrace();
}
// Get and set image
Picasso.with(getContext()).load("http://" + Global.getIpAddress() + ":3000" + adImageURL).into(holder.sharedSpecial);
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.d("Error.Response", error.toString());
}
}
);
requestQueue.add(getCampaignLocationData);
} else if (countries.get(position).campaign_id != "0" && countries.get(position).location_id == "0") {
// Just the campaign is shared
getSharedSpecialURL = specialsActionURL + countries.get(position).campaign_id + JSON;
// Test Campaign id = 41
// GET JSON data and parse
JsonObjectRequest getCampaignData = new JsonObjectRequest(Request.Method.GET, getSharedSpecialURL, null,
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
// Parse the JSON:
try {
resultObject = response.getJSONObject("shared");
} catch (JSONException e) {
e.printStackTrace();
}
// Get and set image
Picasso.with(getContext()).load("http://" + Global.getIpAddress() + ":3000" + adImageURL).into(holder.sharedSpecial);
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.d("Error.Response", error.toString());
}
}
);
requestQueue.add(getCampaignData);
// Location set to empty
}
// If left is true, then yellow, if not then set to green bubble
holder.countryName.setBackgroundResource(countries.get(position).left ? R.drawable.bubble_yellow : R.drawable.bubble_green);
holder.wrapper.setGravity(countries.get(position).left ? Gravity.LEFT : Gravity.RIGHT);
return row;
}
}
The messaging class that sends normal messages only but can receive image messages and set to the adapter:
public class GroupMessaging extends Activity {
private static final int MESSAGE_CANNOT_BE_SENT = 0;
public String username;
public String groupname;
private Button sendMessageButton;
private Manager imService;
private InfoOfGroup group = new InfoOfGroup();
private InfoOfGroupMessage groupMsg = new InfoOfGroupMessage();
private StorageManipulater localstoragehandler;
private Cursor dbCursor;
private com.example.feastapp.ChatBoxUi.DiscussArrayAdapter adapter;
private ListView lv;
private EditText editText1;
private ServiceConnection mConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className, IBinder service) {
imService = ((MessagingService.IMBinder) service).getService();
}
public void onServiceDisconnected(ComponentName className) {
imService = null;
Toast.makeText(GroupMessaging.this, R.string.local_service_stopped,
Toast.LENGTH_SHORT).show();
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.message_activity);
lv = (ListView) findViewById(R.id.listView1);
adapter = new DiscussArrayAdapter(getApplicationContext(), R.layout.message_list_item);
lv.setAdapter(adapter);
editText1 = (EditText) findViewById(R.id.editText1);
sendMessageButton = (Button) findViewById(R.id.sendMessageButton);
Bundle extras = this.getIntent().getExtras();
group.userName = extras.getString(InfoOfGroupMessage.FROM_USER);
group.groupName = extras.getString(InfoOfGroup.GROUPNAME);
group.groupId = extras.getString(InfoOfGroup.GROUPID);
String msg = extras.getString(InfoOfGroupMessage.GROUP_MESSAGE_TEXT);
setTitle("Group: " + group.groupName);
// Retrieve the information
localstoragehandler = new StorageManipulater(this);
dbCursor = localstoragehandler.groupGet(group.groupName);
if (dbCursor.getCount() > 0) {
// Probably where the magic happens, and keeps pulling the same
// thing
int noOfScorer = 0;
dbCursor.moveToFirst();
while ((!dbCursor.isAfterLast())
&& noOfScorer < dbCursor.getCount()) {
noOfScorer++;
}
}
localstoragehandler.close();
if (msg != null) {
// Then friends username and message, not equal to null, recieved
adapter.add(new OneComment(true, group.groupId + ": " + msg, "0", "0"));
adapter.notifyDataSetChanged();
((NotificationManager) getSystemService(NOTIFICATION_SERVICE))
.cancel((group.groupId + msg).hashCode());
}
// The send button
sendMessageButton.setOnClickListener(new OnClickListener() {
CharSequence message;
Handler handler = new Handler();
public void onClick(View arg0) {
message = editText1.getText();
if (message.length() > 0) {
// When general texting, the campaign and location will always be "0"
// Only through specials sharing is the user permitted to change the campaign and location to another value
adapter.add(new OneComment(false, imService.getUsername() + ": " + message.toString(), "0", "0"));
adapter.notifyDataSetChanged();
localstoragehandler.groupInsert(imService.getUsername(), group.groupName,
group.groupId, message.toString(), "0", "0");
// as msg sent, will blank out the text box so can write in
// again
editText1.setText("");
Thread thread = new Thread() {
public void run() {
try {
// JUST PUTTING "0" AS A PLACEHOLDER FOR CAMPAIGN AND LOCATION
// IN FUTURE WILL ACTUALLY ALLOW USER TO SHARE CAMPAIGNS
if (imService.sendGroupMessage(group.groupId,
group.groupName, message.toString(), "0", "0") == null) {
handler.post(new Runnable() {
public void run() {
Toast.makeText(
getApplicationContext(),
R.string.message_cannot_be_sent,
Toast.LENGTH_LONG).show();
// showDialog(MESSAGE_CANNOT_BE_SENT);
}
});
}
} catch (UnsupportedEncodingException e) {
Toast.makeText(getApplicationContext(),
R.string.message_cannot_be_sent,
Toast.LENGTH_LONG).show();
e.printStackTrace();
}
}
};
thread.start();
}
}
});
}
#Override
protected Dialog onCreateDialog(int id) {
int message = -1;
switch (id) {
case MESSAGE_CANNOT_BE_SENT:
message = R.string.message_cannot_be_sent;
break;
}
if (message == -1) {
return null;
} else {
return new AlertDialog.Builder(GroupMessaging.this)
.setMessage(message)
.setPositiveButton(R.string.OK,
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,
int whichButton) {
/* User clicked OK so do some stuff */
}
}).create();
}
}
#Override
protected void onPause() {
super.onPause();
unregisterReceiver(groupMessageReceiver);
unbindService(mConnection);
ControllerOfGroup.setActiveGroup(null);
}
#Override
protected void onResume() {
super.onResume();
bindService(new Intent(GroupMessaging.this, MessagingService.class),
mConnection, Context.BIND_AUTO_CREATE);
IntentFilter i = new IntentFilter();
i.addAction(MessagingService.TAKE_GROUP_MESSAGE);
registerReceiver(groupMessageReceiver, i);
ControllerOfGroup.setActiveGroup(group.groupName);
}
// For receiving messages form other users...
public class GroupMessageReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Bundle extra = intent.getExtras();
//Log.i("GroupMessaging Receiver ", "received group message");
String username = extra.getString(InfoOfGroupMessage.FROM_USER);
String groupRId = extra.getString(InfoOfGroupMessage.TO_GROUP_ID);
String message = extra
.getString(InfoOfGroupMessage.GROUP_MESSAGE_TEXT);
// NEED TO PLACE INTO THE MESSAGE VIEW!!
String received_campaign_id = extra.getString(InfoOfGroupMessage.CAMPAIGN_SHARED);
String received_location_id = extra.getString(InfoOfGroupMessage.LOCATION_SHARED);
// NEED TO INTEGRATE THIS INTO LOGIC ABOVE, SO IT MAKES SENSE
if (username != null && message != null) {
if (group.groupId.equals(groupRId)) {
adapter.add(new OneComment(true, username + ": " + message, received_campaign_id, received_location_id));
localstoragehandler
.groupInsert(username, groupname, groupRId, message, received_campaign_id, received_location_id);
Toast.makeText(getApplicationContext(), "received_campaign: " + received_campaign_id +
" received_location:" + received_location_id, Toast.LENGTH_LONG).show();
received_campaign_id = "0";
received_location_id = "0";
} else {
if (message.length() > 15) {
message = message.substring(0, 15);
}
Toast.makeText(GroupMessaging.this,
username + " says '" + message + "'",
Toast.LENGTH_SHORT).show();
}
}
}
}
;
// Build receiver object to accept messages
public GroupMessageReceiver groupMessageReceiver = new GroupMessageReceiver();
#Override
protected void onDestroy() {
super.onDestroy();
if (localstoragehandler != null) {
localstoragehandler.close();
}
if (dbCursor != null) {
dbCursor.close();
}
}
}

I have gone through your code and this is common problem with listview that images starts repeating itself. In your case I think you have assigned image to Imageview every if and else if condition but if none of the condition satisfy it uses the previous image.
I would suggest to debug the getview method and put break points on the setImageResource. I use volley for these image loading and it has a method called defaultImage so that if no url is there the image is going to get the default one. So add that default case and see if it works.
If any of the above point is not clear feel free to comment.

Android ListView wrong images

I'm developing an Android app but I'm a newbie and I got stuck...
My ListView single element has an ImageView and some TextViews, but sometimes (when I scroll the page and there are more than 7-8 elements) it doesn't display the right image in the right row.
I'm using a custom Image Loader to manage the downloaded images.
Here's my Adapter:
public class AddVideogameActivityAdapter extends BaseAdapter {
private ArrayList<Videogame> videogames;
private Typeface typefaceMedium;
private Typeface typefaceLight;
private ImageLoader loader;
private LayoutInflater mInflater;
public AddVideogameActivityAdapter(Context context, ArrayList<Videogame> results) {
videogames = results;
mInflater = LayoutInflater.from(context);
typefaceMedium = Typeface.createFromAsset(context.getAssets(), "Roboto-Medium.ttf");
typefaceLight = Typeface.createFromAsset(context.getAssets(), "Roboto-Light.ttf");
loader = new ImageLoader(context);
}
public int getCount() {
return videogames.size();
}
public Object getItem(int position) {
return videogames.get(position);
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = mInflater.inflate(R.layout.list_element,null);
holder = new ViewHolder();
holder.imgView = (ImageView) convertView.findViewById(R.id.thumbView);
holder.txtName = (TextView) convertView.findViewById(R.id.elementView);
holder.txtPlatform = (TextView) convertView.findViewById(R.id.elementView2);
convertView.setTag(holder);
}
else {
holder = (ViewHolder) convertView.getTag();
}
try {
Videogame vgame = (Videogame) videogames.get(position);
holder.txtName.setText(vgame.getTitle());
holder.txtName.setTypeface(typefaceMedium);
holder.txtPlatform.setText(videogames.get(position).getPlatform());
holder.txtPlatform.setTypeface(typefaceLight);
holder.imgUrl = videogames.get(position).getImage();
loader.display(holder.imgUrl, holder.imgView, R.drawable.youtube_icon);
}
catch (Exception e) {
e.printStackTrace();
Log.e(com.example.ludos2_0.MainActivity.TAG,
"Exception: " + e.getLocalizedMessage());
}
return convertView;
}
static class ViewHolder {
TextView txtName;
TextView txtPlatform;
public String imgUrl;
ImageView imgView;
}
}
Sorry for my english and thank you for your help!
EDIT:
Here's also the Loader:
public class ImageLoader implements ComponentCallbacks2 {
private TCLruCache cache;
public ImageLoader(Context context) {
ActivityManager am = (ActivityManager) context.getSystemService(
Context.ACTIVITY_SERVICE);
int memoryClass = am.getMemoryClass() * 1024 * 1024;
cache = new TCLruCache(memoryClass);
}
public void display(String url, ImageView imageview, int defaultresource) {
imageview.setImageResource(defaultresource);
Bitmap image = cache.get(url);
if (image != null) {
imageview.setImageBitmap(image);
}
else {
new SetImageTask(imageview).execute(url);
}
}
private class TCLruCache extends LruCache<String, Bitmap> {
public TCLruCache(int maxSize) {
super(maxSize);
}
}
private class SetImageTask extends AsyncTask<String, Void, Integer> {
private ImageView imageview;
private Bitmap bmp;
public SetImageTask(ImageView imageview) {
this.imageview = imageview;
}
#Override
protected Integer doInBackground(String... params) {
String url = params[0];
try {
bmp = getBitmapFromURL(url);
if (bmp != null) {
cache.put(url, bmp);
}
else {
return 0;
}
} catch (Exception e) {
e.printStackTrace();
return 0;
}
return 1;
}
#Override
protected void onPostExecute(Integer result) {
if (result == 1) {
imageview.setImageBitmap(bmp);
}
super.onPostExecute(result);
}
private Bitmap getBitmapFromURL(String src) {
try {
URL url = new URL(src);
HttpURLConnection connection
= (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(input);
return myBitmap;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
}
}
RE-EDIT
Activity code:
public class AddVideogameActivity extends ListActivity {
private TextView searchField = null;
private final Handler handler = new Handler();
private ArrayList<Videogame> videogamesList = null;
private static AddVideogameActivity mContext = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add_book);
mContext = this;
searchField = (TextView) findViewById(R.id.searchField);
searchField.setMaxLines(1);
searchField.setOnFocusChangeListener(new OnFocusChangeListener() {
#Override
public void onFocusChange(View v, boolean hasFocus) {
searchField.setHint("");
}
});
// Setup the list view and its listener
getListView().setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Log.d(MainActivity.TAG,
"AddBookActivity ---> AddButton:onClick()");
// Sets typefaces for TextView
String videogameId = videogamesList.get(position).getId();
String videogameName = videogamesList.get(position).getTitle();
String thumbnail = videogamesList.get(position).getThumbnail();
String description = videogamesList.get(position)
.getDescription();
String image = videogamesList.get(position).getImage();
String platform = videogamesList.get(position).getPlatform();
if (videogameName != null && videogameName.length() > 0
&& thumbnail != null && thumbnail.length() > 0
&& description != null && description.length() > 0
&& image != null && image.length() > 0
&& platform != null && platform.length() > 0) {
if (ListsManager.getInstance().addVideogame(
new Videogame(videogameId, videogameName,
thumbnail, image, description, platform)) == 0) {
Log.d(MainActivity.TAG,
"AddBookActivity --> Videogame:[" + videogameId
+ "#" + videogameName + "]");
Toast toast = Toast.makeText(mContext, "["
+ videogameName + "] Saved !",
Toast.LENGTH_LONG);
toast.show();
} else {
Log.e(MainActivity.TAG,
"AddBookActivity --> Error ! Videogame already in the list ! ");
Toast toast = Toast.makeText(mContext,
"Error! Videogame already in the list!",
Toast.LENGTH_LONG);
toast.show();
}
} else {
Log.e(MainActivity.TAG,
"AddBookActivity --> Error ! Invalid Videogame Name or Thumbnail or Id or Deck");
Toast toast = Toast
.makeText(
mContext,
"Error ! Invalid Videogame Name or Thumbnail or Id or Deck",
Toast.LENGTH_LONG);
toast.show();
}
Intent newIntent = new Intent(getApplicationContext(),
MainActivity.class);
startActivity(newIntent);
}
});
// Setup the search button and its listener
Button searchButton = (Button) findViewById(R.id.searchButton);
searchButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Log.d(com.example.ludos2_0.MainActivity.TAG, "Search Game ...");
String searchInputString = searchField.getText().toString();
if (searchInputString != null && searchInputString.length() > 0) {
try {
String requestURL = ("http://www.giantbomb.com/api/search/?api_key=fcf60d6d67b98b0d17b3905d1a90b3fd31ed1e8e&format=json&query="
+ Uri.encode(searchInputString) + "&resources=game");
// String requestURL =
// String.format("https://gdata.youtube.com/feeds/api/videos?v=2&alt=jsonc&category=Music&orderby=relevance&q=%s",Uri.encode(searchInputString));
Log.d(com.example.ludos2_0.MainActivity.TAG, requestURL);
DownloadGiantBombJSONData giantbombAsyncTask = new DownloadGiantBombJSONData();
giantbombAsyncTask.execute(new String[] { requestURL });
} catch (Exception e) {
e.printStackTrace();
}
}
}
});
if (videogamesList == null)
videogamesList = new ArrayList<Videogame>();
else
updateVideogamesListView(videogamesList);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.add_book, menu);
return true;
}
#Override
protected void onResume() {
super.onResume();
}
#Override
protected void onPause() {
super.onPause();
}
public void updateVideogamesListView(ArrayList<Videogame> values) {
AddVideogameActivityAdapter adapter = new AddVideogameActivityAdapter(this, values);
setListAdapter(adapter);
}
#Override
protected void onDestroy() {
super.onDestroy();
}
}
The other classes involved in building the ListView are the REST classes and the AsyncTask class that downloads and parses the JSon files.

What does your ListView look like, does it look like this:
<ListView android:id="#id/android:list"
android:layout_weight="1"
android:layout_width="match_parent"
android:layout_height="0dip" ></ListView>
Especially the id of the ListView. Check your layout file, probably the bug exists there.

Android: Change image for a particular item in listview

In the above image, there is a list view which contains list of items that the user can download. This is the image which tells user that he can download the file. On completion of download, the image will change to . My problem is when I download a file, the status image(which denotes that download has completed) gets changed for another row, instead, it should change for the row that I had selected. At present, if I download first file in the list, the image gets changed for 4th or 5th item in the list. Also, when I try to download any other file from the list. it opens up last downloaded file(This is functionality of the app that if file is already downloaded, then open it in pdf reader),i.e., if I download 1st file in the list and then go for second item,then instead of downloading 2nd file, it opens up last downloaded file. More over, if I scroll the listview, the status of download gets changed for other items in the list also. Below,is my adapter code:
public class DownloadListAdapter extends BaseAdapter {
Context ctx;
public ArrayList<DownloadListDao> mDownloadList;
String readMoreLink;
public static final String TAG = "DownloadListAdapter";
ProgressDialog mProgressDialog;
private boolean isSDCardPresent;
File tieDir;
int downloadState[];
public DownloadListAdapter(Context ctx,
ArrayList<DownloadListDao> mDownloadList) {
this.ctx = ctx;
this.mDownloadList = mDownloadList;
downloadState = new int [mDownloadList.size()];
for(int i = 0; i < mDownloadList.size(); i++) {
downloadState[i] = 0;
}
tieDir = new File(Environment.getExternalStorageDirectory().toString()
+ "/tie");
}// Constructor
public int getCount() {
return this.mDownloadList.size();
}// getCount
public Object getItem(int position) {
return this.mDownloadList.get(position);
}// getItem
public long getItemId(int position) {
return 0;
}// getItemId
static class ViewHolder {
TextView txtTitle, txtTheme, txtDate;
ImageView imgDownload;
}// ViewHolder
ViewHolder holder;
public View getView(final int position, View convertView, ViewGroup parent) {
final String url = mDownloadList.get(position).getUrl();
if (convertView == null) {
convertView = LayoutInflater.from(parent.getContext()).inflate(
R.layout.downlist_adapter, null);
holder = new ViewHolder();
holder.txtTitle = (TextView) convertView
.findViewById(R.id.txtTitle);
holder.txtTheme = (TextView) convertView
.findViewById(R.id.txtTheme);
holder.txtDate = (TextView) convertView.findViewById(R.id.txtDate);
holder.imgDownload = (ImageView) convertView
.findViewById(R.id.imgDload);
holder.imgDownload.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
File mediaFile = null;
if (url != null && !url.equals("null") && !url.equals("")) {
String fileName = url.toString().substring(
url.toString().lastIndexOf("/") + 1,
url.toString().length());
mediaFile = new File(tieDir, fileName);
}
processFile(mediaFile, url, position);
int pos = (Integer)v.getTag();
downloadState[pos] = 1;
}
});
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
if (mDownloadList != null && mDownloadList.size() > 0) {
if (mDownloadList.get(position).getTitle() != null
&& !mDownloadList.get(position).getTitle().equals("null")
&& !mDownloadList.get(position).getTitle().equals("")) {
holder.txtTitle.setText(mDownloadList.get(position).getTitle());
}
if (mDownloadList.get(position).getTheme() != null
&& !mDownloadList.get(position).getTheme().equals("null")
&& !mDownloadList.get(position).getTheme().equals("")) {
holder.txtTheme.setText(mDownloadList.get(position).getTheme());
}
if (mDownloadList.get(position).getDate() != null
&& !mDownloadList.get(position).getDate().equals("null")
&& !mDownloadList.get(position).getDate().equals("")) {
holder.txtDate.setText(mDownloadList.get(position).getDate());
}
if (downloadState[position] == 1) {
holder.imgDownload.setImageDrawable(ctx.getResources()
.getDrawable(R.drawable.ic_dloaded));
} else {
holder.imgDownload.setImageDrawable(ctx.getResources()
.getDrawable(R.drawable.ic_dload));
}
}
holder.imgDownload.setTag(position);
return convertView;
}// getView
protected void downloadFile(String url, int position, String fileName) {
Log.v(TAG, "Preparing to download");
mProgressDialog = new ProgressDialog(ctx);
mProgressDialog.setMessage("Dowloading...");
mProgressDialog.setIndeterminate(false);
mProgressDialog.setMax(100);
mProgressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
isSDCardPresent = Environment.getExternalStorageState().equals(
Environment.MEDIA_MOUNTED);
if (!isSDCardPresent) {
noSDCardAlert(ctx);
} else {
if ((tieDir.exists()) && (tieDir != null)) {
if (NetworkConnection.isOnline(ctx)) {
if (tieDir.isDirectory()) {
Log.v(TAG, "if tie dir URL:::" + url);
new DownloadAudioAsync(ctx, position, fileName).execute(url);
}
} else {
((DownloadListActivity) ctx)
.OpenNetErrDialog("Please check your internet connection...");
}
} else {
boolean isDirectoryCreated = tieDir.mkdirs();
if (isDirectoryCreated) {
Log.v(TAG, "if tie not dir URL:::" + url);
if (NetworkConnection.isOnline(ctx)) {
new DownloadAudioAsync(ctx, position, fileName).execute(url);
} else {
((DownloadListActivity) ctx)
.OpenWiFiDialog("Please check your internet connection...");
}
}
}
}
}
private void noSDCardAlert(Context ctx) {
AlertDialog.Builder ad = new AlertDialog.Builder(ctx);
ad.setMessage("No sd card present..");
ad.setPositiveButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
}
});
if (!((DownloadDetail) ctx).isFinishing()) {
ad.show();
}
}
public void OpenDialog(String messageID) {
final Dialog dialog = new Dialog(ctx,
android.R.style.Theme_Translucent_NoTitleBar);
dialog.setContentView(R.layout.dialog_base);
dialog.getWindow().getAttributes().windowAnimations = android.R.style.Animation_Dialog;
dialog.setCancelable(false);
TextView alertMessage = (TextView) dialog.findViewById(R.id.txtMessage);
Button btnOK = (Button) dialog.findViewById(R.id.btnOk);
btnOK.setText("Show");
alertMessage.setText(messageID);
dialog.show();
btnOK.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
dialog.dismiss();
}
});
}
protected void showPdf(File mediaFile) {
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(mediaFile), "application/pdf");
intent.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
ctx.startActivity(intent);
}
public class DownloadAudioAsync extends AsyncTask<String, String, String> {
Context ctx;
int pos;
private ProgressDialog pd;
String fileName;
public DownloadAudioAsync(Context ctx, int pos, String fileName) {
this.ctx = ctx;
this.pos = pos;
this.fileName = fileName;
}
#Override
protected void onPreExecute() {
super.onPreExecute();
Log.v(TAG, "inside on pre execute");
pd = new ProgressDialog(ctx);
pd.setMessage("Downloading...\nPlease wait..");
pd.show();
}
#Override
protected String doInBackground(String... aurl) {
int count;
try {
Log.v(TAG,
"inside do in background with url::"
+ aurl[0].toString());
aurl[0] = aurl[0].replaceAll(" ", "%20");
URL url = new URL(aurl[0]);
URLConnection conexion = url.openConnection();
conexion.connect();
int lenghtOfFile = conexion.getContentLength();
fileName = URLDecoder.decode(fileName, "UTF-8");
InputStream input = new BufferedInputStream(url.openStream());
OutputStream output = new FileOutputStream(tieDir + "/"
+ fileName);
byte data[] = new byte[1024];
long total = 0;
while ((count = input.read(data)) != -1) {
total += count;
publishProgress("" + (int) ((total * 100) / lenghtOfFile));
output.write(data, 0, count);
}
output.flush();
output.close();
input.close();
} catch (Exception e) {
}
return null;
}
#Override
protected void onPostExecute(String unused) {
if (!((DownloadListActivity) ctx).isFinishing()) {
pd.dismiss();
updateView(pos);
}
}
private void updateView(int pos) {
View v = ((DownloadListActivity) ctx).menuListView.getChildAt(pos
- ((DownloadListActivity) ctx).menuListView
.getFirstVisiblePosition());
ImageView imgDloadBtn = (ImageView) v.findViewById(R.id.imgDload);
imgDloadBtn.setImageDrawable(ctx.getResources().getDrawable(
R.drawable.ic_dloaded));
notifyDataSetChanged();
}
}
private void processFile(File mediaFile, String url, int pos) {
if (url != null && !url.equals("null") && !url.equals("")) {
if (mediaFile != null) {
Log.v(TAG, "in processFile FileName " + mediaFile.getName());
Log.v(TAG, "in processFile Position " + pos);
if(!mediaFile.exists()) {
Log.v(TAG, "in processFile Media file doesn't exists");
downloadFile(url, pos, mediaFile.getName());
} else {
Log.v(TAG, "in processFile Media file exists");
try {
showPdf(mediaFile);
} catch (ActivityNotFoundException anfe) {
OpenDialog("PDF Reader is not installed on your device.");
}
}
}
}
}
}// DownloadAdapter
I had read this post for recycling the view(Thanks to Knickedi for in depth explaination). But, I can't figure out where is actual problem.

Issue with getview Method which keep recreating whenever you scroll your view, to handle exact position you have to play with setTag & getTag,check below few stackvoerflow answers to understand setTag & getTag:
Button in ListView using ArrayAdapter
Getting radio button value from custom list in android
and even store downloaded state into one booleanarray like below:
int boxState[];
within adapter constructor, set zero initially:
for (int i = 0; i < getData.size(); i++) {
boxState[i] = 0;
}
within adapter getview method:
holder.imgDownload.setTag(position);
Now you click on download button set value as 1 (Inside onclick of button):
pos = (Integer) v.getTag();
boxState[pos]=1;
At last when you scroll your view check condition into following way(put below code inside getview method):
if (boxState[position] == 0) {
holder.imgDownload.setImageDrawable(ctx.getResources()
.getDrawable(R.drawable.ic_dloaded)); //which aren't downloaded
} else {
holder.imgDownload.setImageDrawable(ctx.getResources()
.getDrawable(R.drawable.ic_dload)); // which are downloaded.
}