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Android TextView SetText null object reference error

I am new to android and I am getting a
Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
error on my app. I have read other questions on here like this one - java.lang.NullPointerException - setText on null object reference but I still get the same issue. My format is a little bit different as this is done in a Fragment and what I am doing is having a Custom Adapter from a listview. Here is my code
fragment_song_genre.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:bind="http://schemas.android.com/tools">
<data class="SongGenreBinding">
<variable
name="handler"
type="com.mgrmobi.joox.fragments.FilterSongGenreFragment" />
</data>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#000">
<RelativeLayout
android:id="#+id/toprow"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="24dp">
<ImageButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:layout_marginLeft="16dp"
android:background="#null"
android:onClick="#{ handler.onCloseClicked }"
android:src="#drawable/search_close" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:layout_marginLeft="80dp"
android:text="Genre"
android:textColor="#fff"
android:textSize="20sp" />
<TextView
android:onClick="#{ handler.reset }"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_centerVertical="true"
android:layout_marginRight="15dp"
android:text="#string/reset"
android:textAllCaps="true"
android:textColor="#fff"
android:textSize="12sp" />
</RelativeLayout>
<ListView
android:id="#+id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#id/toprow"
android:layout_marginTop="24dp"></ListView>
</RelativeLayout>
That is the main page and it has a Listview in the Bottom and here is the fragment that calls that xml layout
public class FilterSongGenreFragment extends BaseFragment {
private SongGenreBinding binding;
private ArrayList<String> genres;
String[] names= {"Johm","Paul","Mike"};
#Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
super.onCreateContextMenu(menu, v, menuInfo);
}
private static final String GENRES_KEY = "genres";
public static FilterSongGenreFragment newInstance(ArrayList<String> genres) {
Bundle args = new Bundle();
args.putStringArrayList(GENRES_KEY, genres);
FilterSongGenreFragment fragment = new FilterSongGenreFragment();
fragment.setArguments(args);
return fragment;
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
binding = DataBindingUtil.inflate(inflater, R.layout.fragment_song_genre, container, false);
binding.setHandler(this);
genres = getArguments().getStringArrayList(GENRES_KEY);
initList();
return binding.getRoot();
}
private void initList() {
// ArrayAdapter adapter = new ArrayAdapter(getActivity(), R.layout.genre_list_text, android.R.id.text1, genres);
FilterSongsAdapter filterSongsAdapter= new FilterSongsAdapter(getActivity(),names);
binding.list.setAdapter(filterSongsAdapter);
binding.list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view,int position, long l) {
((SongFilterListener) getActivity()).onGenreSelected(genres.get(position));
/*
textView = (ImageView) view.findViewById(R.id.selected_genre);
textView.setVisibility(View.VISIBLE);
*/
// close();
}
});
}
private void close() {
getActivity().getFragmentManager().beginTransaction().remove(this).commit();
}
public void onCloseClicked(View view) {
close();
}
public void reset(View view) {
((SongFilterListener) getActivity()).onResetFilters();
close();
}
}
Here is the xml for the listview custom style genre_list_text.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:id="#android:id/text1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_vertical|left"
android:text="Genre"
android:paddingBottom="16dp"
android:paddingLeft="4dp"
android:paddingTop="16dp"
android:textColor="#fff"
android:textSize="16sp" />
<ImageView
android:id="#+id/selected_genre"
android:layout_height="24dp"
android:layout_width="24dp"
android:visibility="invisible"
android:src="#drawable/check_circle"
android:layout_marginStart="140dp"
android:layout_centerVertical="true" />
</RelativeLayout>
and here is my adapter and as stated before the error happens in the SetText area
public class FilterSongsAdapter extends ArrayAdapter<String> {
private Context c;
String[] names= {};
LayoutInflater inflater;
public FilterSongsAdapter(Context context,String[] names) {
super(context,R.layout.genre_list_text,names);
this.c=context;
this.names=names;
}
public static class ViewHolder {
TextView text1;
}
#Override
public View getView(int position,View convertView,ViewGroup parent) {
ViewHolder holder;
if(convertView==null){
holder = new ViewHolder();
inflater = (LayoutInflater) c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.from(c).inflate(R.layout.genre_list_text, null);
// Initialize
holder.text1=(TextView) convertView.findViewById(R.id.text1);
convertView.setTag(holder);
}else {
holder = (ViewHolder) convertView.getTag();
}
holder.text1.setText(names[position]);
return convertView;
}
}
The SetText inside the GetView is throwing the exception every time, that TextView should have 3 objects names from the Names String Array which I have seen that it has. Based on the error I know that i'm setting the SetText before the FindByID method locates the TextView but I have moved things around and nothing works. Any help would be great . I also been following this tutorial for reference https://www.youtube.com/watch?v=99C_UpLcBRk . I do not know if maybe with a Fragment things are different.

in your layout you have given default id to TextView android:id="#android:id/text1".
and in JAVA file you are giving R.id.text1
make changes in xml or java.
ether change in xml from android:id="#android:id/text1" to android:id="#+id/text1"
or in java android.R.id.text1

#Override
public View getView(int position,View convertView,ViewGroup parent) {
ViewHolder holder = new ViewHolder(); //because error says null object reference, it means object of TextView `text1` is not found.
inflater = (LayoutInflater) c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
if(convertView==null){
convertView = inflater.inflate(R.layout.genre_list_text, null);
holder.text1=(TextView) convertView.findViewById(R.id.text1);
holder.text1.setText(names[position]);
convertView.setTag(holder);
}else {
holder = (ViewHolder) convertView.getTag();
}
return convertView;
}
And from your provided XML code, I can see you did not provided a proper id for TextView. Change in XML from android:id="#android:id/text1" to android:id="#+id/text1".

In your genre_list_text.xml change android:id="#android:id/text1" to android:id="#+id/text1"
and in your getView Method
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
ViewHolder holder;
View view = convertView;
if (view == null) {
LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.genre_list_text, parent, false);
viewHolder = new ViewHolder();
holder.text1=(TextView) view.findViewById(R.id.text1);
view.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) view.getTag();
}
holder.text1.setText(names[position]);
return view;
}

onListItemClick is not work for added two clickable items in the list row

I created a ListFragment by using a custom adapter. OnListItemClick is not work after I add a button in the list row. If I click on the list row it should be intent to other class, but now when I click on the list row, it did not have any action. No error and no action. So I think it might because there has two clickable items in the list row, so the onListItemClick is not work. But I do not know how can I solve this problem.
Fragment1.java
public class Fragment1 extends ListFragment implements AdapterInterface{
public Fragment1() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
View rootView = inflater.inflate(R.layout.fragment_show_queue, container, false);
// initialize the items list
mItems = new ArrayList<ListViewItem>();
// initialize and set the list adapter
adapter = new ListViewAdapter2(getActivity(), mItems, this);
setListAdapter(adapter);
return rootView;
}
#Override
public void buttonPressed(int position) {
System.out.println("Fragment1: " + position);
}
#Override
public void onListItemClick(ListView l, View v, int position, long id) {
super.onListItemClick(l, v, position, id);
Intent i = new Intent(getActivity(), QueueDetail.class);
i.putExtra("qid", qid.get(position).toString());
startActivity (i);
}
}
ListViewAdapter2.java
public class ListViewAdapter2 extends ArrayAdapter<ListViewItem> {
AdapterInterface buttonListener;
private int position;
public ListViewAdapter2(Context context, List<ListViewItem> items, AdapterInterface buttonListener) {
super(context, R.layout.listview_layout2, items);
this.buttonListener = buttonListener;
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
ViewHolder viewHolder;
this.position = position;
if(convertView == null) {
// inflate the GridView item layout
LayoutInflater inflater = LayoutInflater.from(getContext());
convertView = inflater.inflate(R.layout.listview_layout2, parent, false);
// initialize the view holder
viewHolder = new ViewHolder();
viewHolder.img = (ImageView) convertView.findViewById(R.id.img);
viewHolder.txt = (TextView) convertView.findViewById(R.id.txt);
viewHolder.smallTxt = (TextView) convertView.findViewById(R.id.smallTxt);
viewHolder.datetime = (TextView) convertView.findViewById(R.id.datetime);
viewHolder.viewBtn = (Button) convertView.findViewById(R.id.viewBtn);
convertView.setTag(viewHolder);
} else {
// recycle the already inflated view
viewHolder = (ViewHolder) convertView.getTag();
}
viewHolder.viewBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
System.out.println("ListViewAdapter: " + position);
buttonListener.buttonPressed(position);
}
});
...
return convertView;
}
private int getViewBtnPosition(){
return position;
}
}
fragment_show_queue.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<!-- TODO: Update blank fragment layout -->
<ListView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="match_parent" >
</ListView>
</FrameLayout>
listview_layout2.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<ImageView
android:id="#+id/img"
android:layout_width="50dp"
android:layout_height="50dp"
android:padding="5dp"
android:layout_alignParentLeft="true"/>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_alignParentTop="true"
android:orientation="vertical"
android:layout_toRightOf="#+id/img"
android:layout_toLeftOf="#+id/datetime"
android:layout_toStartOf="#+id/datetime">
<TextView
android:id="#+id/txt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="15dp" />
<TextView
android:id="#+id/smallTxt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="10dp" />
</LinearLayout>
<TextView
android:id="#+id/datetime"
android:layout_width="60dp"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:text=""
android:textSize="10dp" />
<Button
android:layout_width="35dp"
android:layout_height="20dp"
android:id="#+id/viewBtn"
android:text="JOIN"
android:textSize="10dp"
android:background="#b5e61d"
android:layout_marginRight="10dp"
android:layout_centerVertical="true"
android:layout_alignParentRight="true"/>
</RelativeLayout>

add android:focusable="false" and android:focusableInTouchMode="false" to your Button in the row's layout file.

ListFragment doesn't seem be inflating

Hoping someone can help. I'm having an issue it seems inflating my view. My goal is to display a list of items in a custom layout using a custom array adapter. I re-worked some of my original code using another SO post, but where my simple adapter worked fine, the new list doesn't display. Please see below:
This is my Fragment class.
HomeFeedFragment.java
public class HomeFeedFragment extends ListFragment {
private ListView listView;
private ArrayList<MainEvent> items;
private MainEventListViewAdapter adapter;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_homefeed,
container, false);
listView = (ListView) rootView.findViewById(android.R.id.list);
return rootView;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
//GetEvents is just a test method to return a list of pre-filled event objects
items = GlobalList.GetEvents();
adapter = new MainEventListViewAdapter(getActivity(), android.R.id.list, items);
listView.setAdapter(adapter);
}
#Override
public void onListItemClick(ListView l, View v, int position, long id) {
// do something with the data
}
}
My custom row layout xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:padding="5dip" >
<!-- ListRow Left sied Thumbnail image -->
<LinearLayout
android:id="#+id/thumbnail"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_marginRight="5dip"
android:padding="3dip" >
<ImageView
android:id="#+id/list_image"
android:layout_width="50dip"
android:layout_height="50dip" />
</LinearLayout>
<!-- Heading Text -->
<TextView
android:id="#+id/eventheader"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="#+id/thumbnail"
android:layout_toRightOf="#+id/thumbnail"
android:textColor="#040404"
android:textSize="15sp"
android:textStyle="bold"
android:typeface="sans" />
<!-- Event Description -->
<TextView
android:id="#+id/eventdescription"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/thumbnail"
android:layout_below="#id/eventheader"
android:layout_marginTop="1dip"
android:layout_toRightOf="#+id/thumbnail"
android:textColor="#343434"
android:textSize="10sp"
tools:ignore="SmallSp" />
<!-- Posted Time -->
<TextView
android:id="#+id/eventpostedtime"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignTop="#id/eventheader"
android:layout_marginRight="5dip"
android:gravity="right"
android:textColor="#10bcc9"
android:textSize="10sp"
android:textStyle="bold"
tools:ignore="SmallSp" />
</RelativeLayout>
The actual fragment layout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ListView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
And my custom ArrayAdapter:
public class MainEventListViewAdapter extends ArrayAdapter<MainEvent> {
private Context context;
private List<MainEvent> eventList;
public MainEventListViewAdapter(Context context, int textViewResourceId, List<MainEvent> eventList){
super(context, textViewResourceId, eventList);
this.context = context;
//this.eventList = eventList;
}
/*private view holder class*/
private class ViewHolder {
ImageView imageView;
TextView txtEventHeader;
TextView txtEventDescription;
TextView txtEventPostedTime;
}
public int getCount(){
if(eventList!=null){
return eventList.size();
}
return 0;
}
public MainEvent getItem(int position){
if(eventList!=null){
return eventList.get(position);
}
return null;
}
public long getItemId(int position){
if(eventList!=null){
return eventList.get(position).hashCode();
}
return 0;
}
public View getView(int position, View convertView, ViewGroup parent){
ViewHolder holder = null;
MainEvent rowItem = getItem(position);
LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
if(convertView==null){
convertView = inflater.inflate(R.layout.fragment_homefeed_rowlayout, parent, false);
holder = new ViewHolder();
holder.txtEventHeader = (TextView) convertView.findViewById(R.id.eventheader);
holder.txtEventDescription = (TextView) convertView.findViewById(R.id.eventdescription);
holder.txtEventPostedTime = (TextView) convertView.findViewById(R.id.eventpostedtime);
convertView.setTag(holder);
}else{
holder = (ViewHolder) convertView.getTag();
}
holder.txtEventHeader.setText(rowItem.getHeadline());
holder.txtEventDescription.setText(rowItem.getDescription());
holder.txtEventPostedTime.setText(rowItem.getPostedTime());
/*TextView text = (TextView) v.findViewById(R.id.label);
text.setText(m.getHeadline());
ImageView imageView = (ImageView) v.findViewById(R.id.icon);
imageView.setTag(m.getImageURL());
//DownloadImageTask dt = new DownloadImageTask();
dt.execute(imageView);
return v;*/
return convertView;
}
public List<MainEvent> getEventList(){
return eventList;
}
public void setEventList(List<MainEvent> eventList){
this.eventList = eventList;
}
}
^ I initially had an Async Task in this class to retrieve images for each item, but I've removed all of that for now.
I don't get any actual errors in LogCat, no crashes or anything, the View just isn't inflating. Any help is appreciated.

Well this is embarrassing. I found out the issue. Apparently, I forgot to uncomment the line in the adapter constructor that initializes the event list:
//this.eventList = eventList;
I'd commented it out temporarily to fix another bug. Working fine now, but thanks for your suggestion.

Custom Adapter ViewHolder issue

I'm trying to use a custom adapter for a list. This list has 2 types of rows but I only use one layout (keeping the items that I don't need with visibility set to View.GONE). However I keep getting a Class cast exception when trying to access the editbox-style row. I have very little experience with custom adapters. Your help is really appreciated :D
Here's the code(I removed the setonclicklisteners to keep it short):
public class SubEventListAdapter extends ArrayAdapter<MobileSubEvent>
{
private ArrayList<MobileSubEvent> _items;
private Context _context;
public SubEventListAdapter(Context context, ArrayList<MobileSubEvent> items)
{
super(context, R.layout.view_select_event_item3, items);
this._items = items;
this._context = context;
}
static class ViewHolder
{
TextView text;
ImageButton imagebutton;
ImageView check;
EditText editText;
Button button;
}
#Override
public int getCount()
{
return this._items.size();
}
#Override
public View getView(final int position, View convertView, ViewGroup parent)
{
View v = convertView;
final ViewHolder viewHolder;
final MobileSubEvent event = _items.get(position);
if (v == null)
{
LayoutInflater _inflater = (LayoutInflater) this.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
v = _inflater.inflate(R.layout.view_select_event_item3, null);
viewHolder = new ViewHolder();
viewHolder.imagebutton = (ImageButton) v.findViewById(R.id.ibNext);
viewHolder.text = (TextView) v.findViewById(R.id.EVENT);
viewHolder.check = (ImageView) v.findViewById(R.id.ivCheck);
viewHolder.button = (Button) v.findViewById(R.id.bScanOrSign);
viewHolder.editText = (EditText) v.findViewById(R.id.etInput);
v.setTag(viewHolder);
} else
{
v = convertView;
viewHolder = (ViewHolder) v.getTag(); //here is where the class cast exception occurs
}
if (viewHolder.text != null)
viewHolder.text.setText(this._items.get(position).get_description());
v.setTag(this._items.get(position));
...
return v;
}
Logcat:
view_select_event_item3:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#android:color/transparent"
android:padding="5dip" >
<ImageView
android:id="#+id/ivCheck"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_gravity="center_vertical"
android:background="#drawable/check"
android:focusable="false"
android:visibility="invisible" />
<TextView
android:id="#+id/EVENT"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="#id/ivCheck"
android:background="#android:color/transparent"
android:padding="5dp"
android:text="Sample text"
android:textSize="20sp"
android:textStyle="bold"
android:visibility="visible"
/>
<EditText
android:id="#+id/etInput"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:minWidth="130dp"
android:maxWidth="165dp"
android:layout_toRightOf="#id/ivCheck"
android:background="#android:drawable/editbox_background"
android:padding="5dp"
android:hint="Hint text"
android:singleLine="true"
android:text=""
android:textSize="20sp"
android:visibility="invisible"
/>
<Button
android:id="#+id/bScanOrSign"
android:layout_width="62dp"
android:layout_height="32dp"
android:layout_gravity="center_vertical"
android:layout_toLeftOf="#id/ibNext"
android:text="Scan"
android:visibility="invisible"
/>
<ImageButton
android:id="#+id/ibNext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_gravity="right|center_vertical"
android:background="#drawable/right"
android:visibility="invisible" />
</RelativeLayout>

Try this in the getView, check for class name of the convertView object (The View Holder object) if it does not matches class name of your ViewHolder (in my case it is VisitsListViewHolder) - set it as null so new instance is created for the view holder
if(convertView != null)
{
String className = convertView.getTag().getClass().getName();
if(!className.equalsIgnoreCase("VisitsListViewHolder"))
{
convertView = null;
}
}

Simple snippet of ListView and getView

I want a simple snippet of a ListView which is composed of items taken from a dataset array which also makes use of getView() method. ListView only contains text entries unlike text and images both.

http://www.ezzylearning.com/tutorial.aspx?tid=1763429
<TextView android:id="#+id/txtTitle"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center_vertical"
android:layout_alignParentTop="true"
android:layout_alignParentBottom="true"
android:textStyle="bold"
android:textSize="22dp"
android:textColor="#000000"
android:layout_marginTop="5dp"
android:layout_marginBottom="5dp" />
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = convertView;
WeatherHolder holder = null;
if(row == null)
{
LayoutInflater inflater = ((Activity)context).getLayoutInflater();
row = inflater.inflate(layoutResourceId, parent, false);
holder = new WeatherHolder();
holder.txtTitle = (TextView)row.findViewById(R.id.txtTitle);
row.setTag(holder);
}
else
{
holder = (WeatherHolder)row.getTag();
}
Weather weather = data[position];
holder.txtTitle.setText(weather.title);
return row;
}