I use this code to update the listview of my project but i get duplicates by using the listview.invalidateViews(); method. Also i tried the notifyDataSetChanged method by calling it from the customadapter of mine that extends baseadapter but it does not seem to work properly. I need to update using the postexecute method after downloading the data from online source. Please check below my code.
The HomeFragment
public class HomeFragment extends Fragment {
private HomeViewModel homeViewModel;
Bitmap mIcon12;
private ProgressDialog pDialog;
private ArrayList< String> arrayList;
ArrayList<HashMap<String,String>> aList;
private int scrollState;
private int offset = 0;
private Button btnLoadMore;
private boolean flag = false;
private boolean loadingMore = false;
TextView textinput2;
ImageView lv1;
View root;
View root1;
ProgressBar pb;
private int scrollpos;
private ListView lv;
public ArrayList<SubjectData> arrayList1;
CustomAdapter adapter1;
public View onCreateView(@NonNull LayoutInflater inflater,
ViewGroup container,Bundle savedInstanceState) {
homeViewModel =
new ViewModelProvider(this).get(HomeViewModel.class);
root = inflater.inflate(R.layout.fragment_home, container, false);
root1 = inflater.inflate(R.layout.listitem, container, false);
final TextView textView = root.findViewById(R.id.text_home);
lv = root.findViewById(R.id.homelistview);
lv1=root1.findViewById(R.id.flagimageview);
arrayList1 = new ArrayList<SubjectData>();
lv.setClickable(true);
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Object o = lv.getItemAtPosition(position);
Toast.makeText(getContext(), "myPosss "+position, Toast.LENGTH_LONG).show();
}
});
MainActivity main1 = (MainActivity)getActivity();
if (savedInstanceState == null) {
adapter1 = new CustomAdapter(getContext(), arrayList1);
System.out.println("to lv den ine null edopoooooooooooo");
} else {
}
pb = new ProgressBar(getContext());
lv.addFooterView(pb);
lv.setAdapter(adapter1);
if (!flag) {
new loadMoreListView().execute();
flag = true;
System.out.println("to flag1 ine: "+ flag);
}
lv.setOnScrollListener(new AbsListView.OnScrollListener() {
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
}
@Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount,
int totalItemCount) {
scrollpos = totalItemCount;
int lastPos = firstVisibleItem + visibleItemCount;
if ((lastPos == totalItemCount) && (!loadingMore)) {
if (totalItemCount < 250) {
System.out.println("to flag4 ine " + flag);
new loadMoreListView().execute();
} else {
lv.removeFooterView(pb);
}
}
}
});
homeViewModel.getText().observe(getViewLifecycleOwner(), new Observer<String>() {
@Override
public void onChanged(@Nullable String s) {
textView.setText(s);
}
});
return root;
}
private class loadMoreListView extends AsyncTask< Void, Void, String> {
protected String doInBackground(Void... unused) {
loadingMore = true;
String result = null;
String url = "https://api.androidhive.info/json/imdb_top_250.php?offset=" + offset;
try {
URL mUrl = new URL(url);
HttpURLConnection urlConnection = (HttpURLConnection) mUrl.openConnection();
urlConnection.setConnectTimeout(10000); //set timeout to 5 seconds
urlConnection.connect();
InputStream inputStream = urlConnection.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(inputStream));
StringBuffer buffer = new StringBuffer();
String str = "";
while ((str = br.readLine()) != null) {
buffer.append(str);
}
result = buffer.toString();
} catch (Exception e) {
System.out.println("error " + e);
}
return result;
}
/*
* An InputStream that skips the exact number of bytes provided, unless it reaches EOF.
*/
public class FlushedInputStream extends FilterInputStream {
public FlushedInputStream(InputStream inputStream) {
super(inputStream);
}
@Override
public long skip(long n) throws IOException {
long totalBytesSkipped = 0L;
while (totalBytesSkipped < n) {
long bytesSkipped = in.skip(n - totalBytesSkipped);
if (bytesSkipped == 0L) {
int b = read();
if (b < 0) {
break; // we reached EOF
} else {
bytesSkipped = 1; // we read one byte
}
}
totalBytesSkipped += bytesSkipped;
}
return totalBytesSkipped;
}
}
public View getView(int position, View convertView, ViewGroup parent) {
View vi=convertView;
return vi;
}
protected void onPostExecute(String result) {
if (result != null) {
try {
JSONArray array = new JSONArray(result);
for (int i = 0; i < array.length(); i++) {
arrayList1.add(new SubjectData(array.getJSONObject(i).getString("title"),"link", "image"));
}
loadingMore = false;
System.out.println("to flag2 ine: "+ flag);
lv.invalidateViews();
// adapter1.updater(arrayList1);
offset+=20;
} catch (Exception e) {
e.printStackTrace();
}
} else {
if (pb==null)
{
System.out.println("ine null to pb ");
}
else if (lv==null) {
pb.setVisibility(pb.GONE);
Toast.makeText(getContext(), "Please check your internet connection!", Toast.LENGTH_SHORT).show();
pb=null;
}
else
{
lv.removeFooterView(pb);
}
}
}
}
}
And this is the customadapter that extends the baseadapter
public class CustomAdapter extends BaseAdapter {
public ArrayList<SubjectData> arrayList;
Context context;
Thread t;
public CustomAdapter(Context context, ArrayList<SubjectData> arrayList) {
this.context = context;
this.arrayList = arrayList;
}
public void updater(ArrayList<SubjectData> updatedlist)
{
this.arrayList.clear();
this.arrayList.addAll(updatedlist);
this.notifyDataSetChanged();
}
@Override
public boolean areAllItemsEnabled() {
return false;
}
@Override
public boolean isEnabled(int position) {
return true;
}
@Override
public int getCount() {
return arrayList.size();
}
@Override
public Object getItem(int position) {
return position;
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public boolean hasStableIds() {
return false;
}
public View getView(int position, View convertView, ViewGroup parent) {
SubjectData subjectData = arrayList.get(position);
if(convertView == null) {
LayoutInflater layoutInflater = LayoutInflater.from(context);
convertView = layoutInflater.inflate(R.layout.listitem, null);
convertView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
AppCompatActivity activity= (AppCompatActivity)context;
ImageView image = new ImageView(context);
image.setImageResource(R.drawable.notificationstoreicon);
final ProgressBar pb = new ProgressBar(context);
String[] coupons = {"horse", "cow", "camel", "sheep", "goat"};
AlertDialog.Builder builder =
new AlertDialog.Builder(context).
setTitle("Details").
setView(pb).
setMessage("please wait...")
.
setPositiveButton("Go", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
}
})
.setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
// dialog.dismiss();
if (t.isAlive())
{
}
else
{
}
}
});
AlertDialog dialog1=builder.create();
dialog1.show();
t= new Thread()
{ private volatile boolean running = true;
public void run() {
System.out.println("blah");
while (running) {
try {
// thread to sleep for 1000 milliseconds
Thread.sleep(4000);
running=false;
} catch (Exception e) {
System.out.println(e);
}
}
runOnUiThread(new Runnable() {
@Override
public void run() {
dialog1.setMessage("more details");
pb.setVisibility(View.GONE);
Picasso.get()
.load(subjectData.Image)
.into(image);
dialog1.setContentView(image);
}
});
}
public void stopThread() {
running = false;
interrupt();
}
public void runOnUiThread(Runnable runnable){
final Handler UIHandler = new Handler(Looper.getMainLooper());
UIHandler.post(runnable);
}
};
t.start();
}
});
TextView tittle = convertView.findViewById(R.id.txt);
ImageView imag = convertView.findViewById(R.id.flagimageview);
tittle.setText(subjectData.SubjectName);
Picasso.get()
.load(subjectData.Image)
.into(imag);
}
return convertView;
}
@Override
public int getItemViewType(int position) {
return position;
}
@Override
public int getViewTypeCount() {
if(getCount() > 0){
return arrayList.size();
}else{
return 1;
}
}
@Override
public boolean isEmpty() {
return false;
}
}
Fragment home xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".ui.home.HomeFragment">
<TextView
android:id="@+id/text_home"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:text="Please check your internet connection!"
android:textAlignment="center"
android:textSize="20sp"
android:visibility="invisible"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:visibility="invisible" />
<ListView
android:id="@+id/homelistview"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<ImageView
android:id="@+id/helloimageview"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:contentDescription="productimage"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
Any help appreciated. I searched in other people posts but no luck! I have been searching for hours actually!
Can anyone help me? Cant find solution!
invalidateViewsu only need to calladapter1.notifyDataSetChanged(). Debug your code see if data is getting parsed and getting added in array List properly. – Extracanonicalwhen i call notifyDataSetChanged() it keeps triggering Oncreate from HomeFragment. That should not happen its probably means Your app getting crashed . Check the Logs and add the error stacktrace with question. – Extracanonical