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OnClickListener in ViewHolder not being entered

I have a recycler view displaying all posts made by a user in my app. I want the users to be able to click on one of the posts and be brought to a new fragment where they can only see the post they have chosen.
When I run my code, and click on one of the posts, the OnCLickListener isn't even triggered.
I have tried adding break points on public void OnClick but it never gets triggered. I have tried adding the OnClick to the onBindViewHolder but I understand this isn't a good idea.
public class PostAdapter extends RecyclerView.Adapter<PostAdapter.PostViewHolder> {
public List<Post> postList;
private Context context;
private static OnItemClickListener onItemClickListener;
public PostAdapter(){
}
public interface OnItemClickListener{
void onItemClick(View v, int position);
}
public void updateList(List<Post> list){
postList = list;
notifyDataSetChanged();
}
public static class PostViewHolder extends RecyclerView.ViewHolder{
TextView postName, postUsername, postDate, postTime, postContent, postId;
PostViewHolder(View v) {
super(v);
this.postName = (TextView) itemView.findViewById(R.id.name);
this.postUsername = (TextView) itemView.findViewById(R.id.username);
this.postDate = (TextView) itemView.findViewById(R.id.date);
this.postTime = (TextView) itemView.findViewById(R.id.time);
this.postContent = (TextView) itemView.findViewById(R.id.content);
this.postId = (TextView) itemView.findViewById(R.id.postId);
v.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
int position = PostViewHolder.super.getAdapterPosition();
onItemClickListener.onItemClick(v, position);
System.out.println("doesn't even make it here");
}
});
}
}
public PostAdapter(List<Post> postList, Context context){
this.postList = postList;
this.context = context;
}
#Override
public PostAdapter.PostViewHolder onCreateViewHolder(ViewGroup parent, int viewType){
View view = LayoutInflater.from(context).inflate(R.layout.all_posts_layout, parent, false);
return new PostAdapter.PostViewHolder(view);
}
#Override
public void onBindViewHolder(PostViewHolder holder, int position){
Post post = postList.get(position);
holder.postUsername.setText(String.valueOf(post.getUsername()));
holder.postName.setText(String.valueOf(post.getName()));
holder.postDate.setText(String.valueOf(post.getDate()));
holder.postTime.setText(String.valueOf(post.getTime()));
}
#Override
public int getItemCount(){
return this.postList.size();
}
Any help would be very much appreciated!
<---card layout for each individual post---->
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="130dp"
android:orientation="vertical">
<ScrollView
android:layout_width="wrap_content"
android:layout_height="130dp">
<android.support.v7.widget.CardView
android:id="#+id/card_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginLeft="16dp"
android:layout_marginTop="16dp"
android:layout_marginRight="16dp"
android:layout_marginBottom="2dp"
android:elevation="60dp">
<RelativeLayout
android:id="#+id/search_term_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="1dp">
<TextView
android:id="#+id/name"
android:layout_width="wrap_content"
android:textStyle="bold"
android:layout_height="wrap_content"
android:text="Name"
android:textSize="20sp" />
<TextView
android:id="#+id/username"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textStyle="italic"
android:layout_marginLeft="10dp"
android:layout_toRightOf="#id/name"
android:text="Username"
android:textSize="18sp" />
<TextView
android:id="#+id/date"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/content"
android:layout_alignParentEnd="true"
android:layout_marginEnd="56dp"
android:text="Date"
android:textSize="10sp" />
<TextView
android:id="#+id/time"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/username"
android:layout_toRightOf="#+id/username"
android:layout_alignParentEnd="true"
android:paddingLeft="8dp"
android:text="Time"
android:textSize="10sp" />
<TextView
android:id="#+id/content"
android:layout_width="315dp"
android:layout_height="48dp"
android:layout_below="#+id/name"
android:layout_alignStart="#+id/name"
android:text="Content"
android:textSize="18sp" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/postId"
android:text="ID"
android:layout_below="#id/content"
/>
</RelativeLayout>
</android.support.v7.widget.CardView>
</ScrollView>
</LinearLayout>
<---recycler view to display all posts------>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:tools="http://schemas.android.com/tools">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/filterBtn"
android:text="Filter"
android:background="#drawable/button"
android:layout_margin="2dp"
android:textColor="#color/common_google_signin_btn_text_dark_default"/>
<android.support.v7.widget.RecyclerView
android:id="#+id/update_post_view"
android:layout_width="match_parent"
android:layout_marginTop="50dp"
android:padding="10dp"
android:layout_height="match_parent" />
</RelativeLayout>

Seems like your ScrollView consumes click event. Try to remove it or replace with NestedScrollView

You need to set it in onCreateViewHolder on that view. Also init it in the constructor.

Update code according to this
public static class PostViewHolder extends RecyclerView.ViewHolder, View.OnClickListener {
TextView postName, postUsername, postDate, postTime, postContent, postId;
PostViewHolder(View v) {
super(v);
//init view
v.setOnClickListener(this);
}
#Override
public void onClick(View v) {
onItemClickListener.onItemClick(v, getAdapterPosition());
}
}

**=> You just need to change onBindViewHolder() method code
=> Add click listener on this method.
=> Your code should be like this.**
#Override
public void onBindViewHolder(PostViewHolder holder, int position){
Post post = postList.get(position);
holder.postUsername.setText(String.valueOf(post.getUsername()));
holder.postName.setText(String.valueOf(post.getName()));
holder.postDate.setText(String.valueOf(post.getDate()));
holder.postTime.setText(String.valueOf(post.getTime()));
holder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
int position = PostViewHolder.super.getAdapterPosition();
onItemClickListener.onItemClick(v, position);
System.out.println("doesn't even make it here");
}
});
}

How can i Add the click listeners to the child of Recycler View?

Here is my discussion.java which contains the RecyclerView
public class Discussion extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_discussion);
RecyclerView mRecycleview =(RecyclerView)findViewById(R.id.cycleview);
mRecycleview.setLayoutManager(new LinearLayoutManager(this));
String[] use ={"a","b"};
String[] lo={"be","ndls"};
String[] ti={"12:00","11:00"};
String[] staus={"Today","Tommmorow"};
int[] posimg={R.drawable.img_post1,R.drawable.img_post2};
mRecycleview.setAdapter(new FeedAdapter(use,lo,ti,staus,posimg));
#NonNull
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Open Activity for posting", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
// Functionality for poll
}
}
Here is my FeedAdapter for the RecyclerView which is taking from resource layout file content.xml.
public class FeedAdapter extends
RecyclerView.Adapter<FeedAdapter.FeedViewHolder> {
private String[] userdata;
private String[] locdata;
private String[] timedata;
private int[] postdata;
private String[] statusdata;
public FeedAdapter(String[] userdata,String[] locdata,String[] timedata,String[] statusdata,int[] postdata){
this.userdata=userdata;
this.locdata=locdata;
this.postdata=postdata;
this.statusdata=statusdata;
this.timedata=timedata;
}
#Override
public FeedViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater=LayoutInflater.from(parent.getContext());
View view =inflater.inflate(R.layout.backupofcontent,parent,false);
return new FeedViewHolder(view);
}
#Override
public void onBindViewHolder( FeedAdapter.FeedViewHolder holder, int position) {
String user=userdata[position];
String loc=locdata[position];
String time=timedata[position];
String status=statusdata[position];
int post=postdata[position];
holder.username.setText(user);
holder.locationa.setText(loc);
holder.timea.setText(time);
holder.statusa.setText(status);
if(post==0)
holder.postimg.setVisibility(View.GONE);
else
holder.postimg.setImageResource(post);
}
#Override
public int getItemCount() {
return userdata.length;
}
public class FeedViewHolder extends RecyclerView.ViewHolder{
ImageView postimg;
TextView username;
TextView locationa;
TextView timea;
TextView statusa;
public FeedViewHolder(View itemView) {
super(itemView);
postimg=itemView.findViewById(R.id.imgView_postPic);
username=itemView.findViewById(R.id.user_name);
locationa=itemView.findViewById(R.id.Location);
timea=itemView.findViewById(R.id.Time);
statusa=itemView.findViewById(R.id.post_text);
}
}
}
Here is my content.xml from which adapter is taking the feed. I want to set up the onClickListner on the view id:likelayout" or like so that when it is clicked, some actions are to be performed. For now, a toast would be enough.
Please help me out how to do it.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
app:layout_behavior="#string/appbar_scrolling_view_behavior"
android:orientation="vertical"
tools:showIn="#layout/app_bar_main"
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">
<TextView
android:id="#+id/user_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center|center_vertical"
android:layout_marginLeft="5dp"
android:layout_marginTop="4dp"
android:text="User"
android:textSize="20sp" />
<TextView
android:id="#+id/Time"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#id/user_name"
android:layout_gravity="center|center_vertical"
android:layout_marginLeft="5dp"
android:layout_marginTop="4dp"
android:text="Time"
android:textSize="10sp" />
<TextView
android:id="#+id/Location"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#id/Time"
android:layout_gravity="center|center_vertical"
android:layout_marginLeft="5dp"
android:layout_marginTop="4dp"
android:text="Location"
android:textSize="10sp" />
<LinearLayout
android:id="#+id/layout_post"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/Location"
android:layout_marginTop="10dp"
android:orientation="vertical">
<ImageView
android:id="#+id/imgView_postPic"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:scaleType="fitCenter"
android:src="#drawable/img_post1" />
<ScrollView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_marginTop="10dp"
android:layout_marginBottom="55dp"
android:layout_weight="1">
<TextView
android:id="#+id/post_text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Status " />
</ScrollView>
</LinearLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="20dp"
android:layout_marginBottom="10dp"
android:gravity="center_vertical"
android:layout_above="#id/bottomnav">
<TextView
android:id="#+id/likecount"
android:layout_marginLeft="20dp"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:text="0"
android:gravity="center" />
<TextView
android:id="#+id/likecounttext"
android:layout_toRightOf="#id/likecount"
android:layout_marginLeft="10dp"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:text="Liked"/>
<TextView
android:layout_toRightOf="#id/likecounttext"
android:layout_marginLeft="15dp"
android:id="#+id/countsepartor"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="|"/>
<TextView
android:id="#+id/commentcount"
android:layout_marginLeft="15dp"
android:layout_toRightOf="#id/countsepartor"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="0"/>
<TextView
android:layout_marginLeft="10dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="#id/commentcount"
android:text="Comments"/>
</RelativeLayout>
<LinearLayout
android:id="#+id/bottomnav"
android:layout_width="match_parent"
android:layout_height="30dp"
android:weightSum="3"
android:layout_marginBottom="5dp"
android:layout_alignParentBottom="true"
android:orientation="horizontal">
<LinearLayout
android:id="#+id/likelayout"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_marginLeft="5dp"
android:layout_gravity="center_vertical"
android:layout_height="wrap_content">
<ImageView
android:layout_width="25dp"
android:layout_height="wrap_content"
android:src="#drawable/like"/>
<TextView
android:id="#+id/like"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Like"
android:layout_marginLeft="10dp"
android:layout_gravity="center_vertical"
android:textSize="15sp"/>
</LinearLayout>
<LinearLayout
android:id="#+id/commentlayout"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_gravity="center_vertical"
android:layout_height="wrap_content">
<ImageView
android:layout_width="25dp"
android:layout_height="wrap_content"
android:src="#drawable/comment"/>
<TextView
android:id="#+id/comment"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Comment"
android:layout_marginLeft="10dp"
android:layout_gravity="center_vertical"
android:textSize="15sp"/>
</LinearLayout>
<LinearLayout
android:id="#+id/polllayout"
android:layout_width="0dp"
android:layout_weight="1"
android:gravity="center"
android:layout_gravity="center_vertical"
android:layout_height="wrap_content">
<ImageView
android:layout_width="25dp"
android:layout_height="wrap_content"
android:src="#drawable/poll"/>
<TextView
android:id="#+id/poll"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Poll"
android:layout_marginLeft="10dp"
android:layout_gravity="center_vertical"
android:textSize="15sp"/>
</LinearLayout>
</LinearLayout>
</RelativeLayout>

In your onBindViewHolder function, just add a click listener like the following.
#Override
public void onBindViewHolder( FeedAdapter.FeedViewHolder holder, int position) {
String user=userdata[position];
String loc=locdata[position];
String time=timedata[position];
String status=statusdata[position];
int post=postdata[position];
holder.username.setText(user);
holder.locationa.setText(loc);
holder.timea.setText(time);
holder.statusa.setText(status);
if(post==0)
holder.postimg.setVisibility(View.GONE);
else
holder.postimg.setImageResource(post);
holder.username.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View view) {
// Do something.
}
});
}
If you want to set up the click listener to the other UI elements in your list item, then just declare them like the way you have declared username, timea, statusa etc. and then add the listener to it.
Please keep in mind that, in order to make an ImageView clickable you need to add the clickable attribute to true in your layout file. For example, if you need to make your like image clickable, you need to add the clickable attribute like the following.
<ImageView
android:id="#+id/like_image"
android:layout_width="25dp"
android:layout_height="wrap_content"
android:clickable="true"
android:src="#drawable/like"/>
In order to show a Toast on clicking the item, you need to have the Context of the Discussion activity while you are creating the adapter. So I would like to suggest you modify the constructor of the adapter like the following.
public class FeedAdapter extends
RecyclerView.Adapter<FeedAdapter.FeedViewHolder> {
private String[] userdata;
private String[] locdata;
private String[] timedata;
private int[] postdata;
private String[] statusdata;
// Add another extra variable to store context
// The context is necessary for showing toast
private Context context;
public FeedAdapter(String[] userdata, String[] locdata,String[] timedata, String[] statusdata, int[] postdata, Context context){
this.userdata = userdata;
this.locdata = locdata;
this.postdata = postdata;
this.statusdata = statusdata;
this.timedata = timedata;
this.context = context; // Initialize it here
}
#Override
public FeedViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater=LayoutInflater.from(parent.getContext());
View view =inflater.inflate(R.layout.backupofcontent,parent,false);
return new FeedViewHolder(view);
}
#Override
public void onBindViewHolder( FeedAdapter.FeedViewHolder holder, int position) {
String user=userdata[position];
String loc=locdata[position];
String time=timedata[position];
String status=statusdata[position];
int post=postdata[position];
holder.username.setText(user);
holder.locationa.setText(loc);
holder.timea.setText(time);
holder.statusa.setText(status);
if(post==0)
holder.postimg.setVisibility(View.GONE);
else
holder.postimg.setImageResource(post);
// Use the context here to show the Toast
holder.username.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View view) {
Toast.makeText(context, "Something", Toast.LENGTH_LOGN).show();
}
});
}
#Override
public int getItemCount() {
return userdata.length;
}
public class FeedViewHolder extends RecyclerView.ViewHolder{
ImageView postimg;
TextView username;
TextView locationa;
TextView timea;
TextView statusa;
public FeedViewHolder(View itemView) {
super(itemView);
postimg=itemView.findViewById(R.id.imgView_postPic);
username=itemView.findViewById(R.id.user_name);
locationa=itemView.findViewById(R.id.Location);
timea=itemView.findViewById(R.id.Time);
statusa=itemView.findViewById(R.id.post_text);
}
}
}
And to adopt the changes of the modified constructor, the adapter needs to be initialized like the following from your Discussion class.
mRecycleview.setAdapter(new FeedAdapter(use, lo, ti, staus, posimg, this));
Hope that helps!

same as the other views, in the FeedViewHolder class add a LinearLayout variable:
LinearLayout like;
then
like = itemView.findViewById(R.id.likelayout);
then in onBindViewHolder use :
holder.like.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View view) {
// Like Layout was clicked
}
});

Getting the progress of multiple seekbars in recycler view

So I am displaying a recylerview with an Image and the name of a person. Below that is a seekbar, which the user can move to rate that person.
Now I want to store the ratings (=progress) of each seekbar in a list. However right now it only stores the rating of the last seekbar in the list.
So it stores only the progress of the last seekbar right now. I would like that when the user clicks the button that every current rating value of every seekbar is stored in a list.
Thank you very much.
That is is my layout_listitem:
<?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="wrap_content"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="3dp"
android:id="#+id/parent_layoutREC"
android:orientation="horizontal"
android:layout_marginTop="13dp"
android:gravity="center">
<de.hdodenhof.circleimageview.CircleImageView
android:paddingTop="2dp"
android:paddingLeft="2dp"
android:layout_width="73dp"
android:layout_height="73dp"
android:id="#+id/kunde_imageREC"
android:src="#mipmap/ic_launcher"/>
<TextView
android:layout_marginLeft="40dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Canada"
android:id="#+id/kunde_nameREC"
android:textColor="#000"
android:textSize="19sp"
android:textStyle="bold"/>
</LinearLayout>
<SeekBar
android:layout_marginRight="35dp"
android:layout_marginLeft="35dp"
android:layout_marginTop="8dp"
android:id="#+id/seek_Bar"
android:max="10"
android:progress="5"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<TextView
android:gravity="center"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="0 1 2 3 4 5"
android:textSize="20sp"/>
That is my RecyclerViewAdapter class:
public class RecyclerViewAdap extends
RecyclerView.Adapter<RecyclerViewAdap.ViewHolder> {
private static final String TAG = "RecyclerViewAdap";
private ArrayList<String> mImageUrl = new ArrayList<>();
private ArrayList<String> mKundeNamen = new ArrayList<>();
public ArrayList<Integer> mBewertungen = new ArrayList<>();
private Context mContext;
public String bewertung;
private TextView progressSeekbar;
public RecyclerViewAdap(ArrayList<String> imageUrl, ArrayList<String> kundeNamen, Context context) {
mImageUrl = imageUrl;
mKundeNamen = kundeNamen;
mContext = context;
}
public class ViewHolder extends RecyclerView.ViewHolder {
CircleImageView imageView;
TextView kundeName;
LinearLayout parentLayout;
SeekBar seekBar1;
public ViewHolder(#NonNull View itemView) {
super(itemView);
imageView = itemView.findViewById(R.id.kunde_imageREC);
kundeName = itemView.findViewById(R.id.kunde_nameREC);
parentLayout = itemView.findViewById(R.id.parent_layoutREC);
seekBar1 = itemView.findViewById(R.id.seek_Bar);
progressSeekbar = itemView.findViewById(R.id.progress_seekbar);
seekBar1.setOnSeekBarChangeListener(seekBarChangeListener);
//int progress = seekBar1.getProgress();
//String.valueOf(Math.abs((long)progress)).charAt(0);
//progressSeekbar.setText("Bewertung: " +
// String.valueOf(Math.abs((long)progress)).charAt(0) + "." + String.valueOf(Math.abs((long)progress)).charAt(1));
}
}
#NonNull
#Override
public ViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.layout_listitem, parent, false);
ViewHolder holder = new ViewHolder(view);
Log.d(TAG, "onCreateViewHolder: ");
return holder;
}
#Override
public void onBindViewHolder(#NonNull ViewHolder holder, final int position) {
Glide.with(mContext)
.load(mImageUrl.get(position))
.into(holder.imageView);
holder.kundeName.setText(mKundeNamen.get(position));
holder.parentLayout.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(mContext, mKundeNamen.get(position),
Toast.LENGTH_SHORT).show();
}
});
holder.seekBar1.setTag(position);
}
#Override
public int getItemCount() {
return mImageUrl.size();
}
SeekBar.OnSeekBarChangeListener seekBarChangeListener = new SeekBar.OnSeekBarChangeListener() {
#Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
// updated continuously as the user slides the thumb
progressSeekbar.setText(String.valueOf(progress));
}
#Override
public void onStartTrackingTouch(SeekBar seekBar) {
// called when the user first touches the SeekBar
}
#Override
public void onStopTrackingTouch(SeekBar seekBar) {
// called after the user finishes moving the SeekBar
if (seekBar.getTag().toString().equals("1")) {
mBewertungen.add(seekBar.getProgress());
if (mBewertungen.size() == 2) {
mBewertungen.remove(0);
Toast.makeText(mContext, "onProgressChanged: " + mBewertungen.toString(), Toast.LENGTH_SHORT).show();
}
}
if (seekBar.getTag().toString().equals("2")) {
mBewertungen.add(seekBar.getProgress());
if (mBewertungen.size() == 3) {
mBewertungen.remove(1);
Toast.makeText(mContext, "onProgressChanged: " + mBewertungen.toString(), Toast.LENGTH_SHORT).show();
}
}
}
};
}
That is the activity where the Recyclerview is being displayed:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
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=".BewertungEsserActvity"
android:orientation="vertical"
app:layoutManager="LinearLayoutManager"
android:background="#drawable/gradient_background">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<include
android:id="#+id/toolbar"
layout="#layout/toolbar" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="14dp"
android:text="Bewerte deine Gäste"
android:textColor="#color/colorDarkGrey"
android:textSize="30sp"
android:textStyle="bold" />
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="#color/colorBlack"
android:layout_marginBottom="10dp"/>
<androidx.recyclerview.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/recycler_view">
</androidx.recyclerview.widget.RecyclerView>
<ProgressBar
android:visibility="invisible"
android:id="#+id/progressbar_4"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="13dp" />
<Button
android:layout_marginRight="66dp"
android:layout_marginLeft="66dp"
android:id="#+id/bewerten_Btn"
android:layout_width="match_parent"
android:layout_height="55dp"
android:layout_marginTop="10dp"
android:background="#drawable/btn_background_profil"
android:padding="10dp"
android:text="Bewerten"
android:textAllCaps="false"
android:textColor="#color/colorWhite"
android:textSize="16sp"
android:textStyle="normal" />
<View
android:layout_marginBottom="10dp"
android:layout_marginTop="34dp"
android:layout_width="match_parent"
android:layout_height="0dp"
android:background="#color/colorBlack" />
</LinearLayout>
</ScrollView>

You can do it in multiple ways:
1- You can store seekbars value as a property in your model and update that property on OnSeekBarChangeListener and when the user hits the button get the data source from the adapter and then run a loop on it and call getter of that attribute.
2- You can store seekbars value as a List<> in your adapter and whenever the user hits the button get the list from the adapter.

custom listview on fragment - can't use getActivity()

I am trying to add delete button next to my item details basing on this answer.
I tried it on a new project, it works perefect:
and when I click delete, I delete the item.
sadly, I tried to use it in my own project when my listView is in calendar_tab.xml. calendar_tab uses CompactCalendarTab.java - fragment class.
so Android Studio errored:
E:\Downloads\MyCustomAdapter.java
Error:(49, 63) error: cannot find symbol method getSystemService(String)
I tried to change
LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
to
LayoutInflater inflater = (LayoutInflater)getActivity().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
but with no luck.
custom_listview.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" >
<TextView
android:id="#+id/list_item_string"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:layout_alignParentLeft="true"
android:paddingLeft="8dp"
android:textSize="18sp"
android:textStyle="bold" />
<Button
android:id="#+id/delete_btn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:layout_marginRight="5dp"
android:text="Delete" />
calendar_tab.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:orientation="vertical"
android:layout_width="match_parent"
android:id="#+id/calendar_tab"
android:layout_height="match_parent"
>
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/toolbar_calendar"
android:background="#color/teal_300"
android:layout_alignParentTop="true"
android:padding="10sp"
android:layout_alignParentStart="true">
<ImageButton
android:id="#+id/back_button"
android:src="#mipmap/ic_arrow_back_black_24dp"
android:background="#null"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_alignParentEnd="true"
android:onClick="goBackmain"
/>
<ImageButton
android:id="#+id/next_button"
android:src="#mipmap/ic_keyboard_arrow_left_black_24dp"
android:background="#null"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_toLeftOf="#+id/showdate"
android:layout_toStartOf="#+id/showdate" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text=""
android:textSize="25sp"
android:textStyle="bold"
android:textColor="#color/black"
android:id="#+id/showdate"
android:layout_alignBaseline="#+id/prev_button"
android:layout_alignBottom="#+id/prev_button"
android:layout_centerHorizontal="true" />
<ImageButton
android:id="#+id/prev_button"
android:src="#mipmap/ic_keyboard_arrow_right_black_24dp"
android:background="#null"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_toRightOf="#+id/showdate"
android:layout_toEndOf="#+id/showdate" />
</RelativeLayout>
<com.github.sundeepk.compactcalendarview.CompactCalendarView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/compactcalendar_view"
android:layout_width="fill_parent"
android:layout_height="250dp"
app:compactCalendarTargetHeight="250dp"
app:compactCalendarTextSize="12sp"
app:compactCalendarBackgroundColor="#null"
app:compactCalendarTextColor="#color/blue_grey_700"
app:compactCalendarCurrentSelectedDayBackgroundColor="#color/teal_300"
app:compactCalendarCurrentDayBackgroundColor="#color/teal_600"
app:compactCalendarCurrentDayIndicatorStyle="fill_large_indicator"
app:compactCalendarEventIndicatorStyle="small_indicator"
app:compactCalendarOtherMonthDaysTextColor="#534c4c"
app:compactCalendarShouldSelectFirstDayOfMonthOnScroll="true"
android:layout_below="#+id/toolbar_calendar"
/>
<ListView
android:id="#+id/bookings_listview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/compactcalendar_view"
>
</ListView>
my fragment:
public class CompactCalendarTab extends Fragment {
final ListView bookingsListView = (ListView) v.findViewById(R.id.bookings_listview);
adapter = new ArrayAdapter<>(getContext(), android.R.layout.simple_list_item_1, mutableBookings);
final ArrayList<String> list = new ArrayList<>();
final MyCustomAdapter adapter = new MyCustomAdapter(list, this);
bookingsListView.setAdapter(adapter);
compactCalendarView = (CompactCalendarView)
v.findViewById(R.id.compactcalendar_view);
}
my custom adapter:
public class MyCustomAdapter extends BaseAdapter implements ListAdapter {
private ArrayList<String> list = new ArrayList<String>();
private CompactCalendarTab context;
public MyCustomAdapter(ArrayList<String> list, CompactCalendarTab context) {
this.list = list;
this.context = context;
}
#Override
public int getCount() {
return list.size();
}
#Override
public Object getItem(int pos) {
return list.get(pos);
}
#Override
public long getItemId(int pos) {
return 0;
//just return 0 if your list items do not have an Id variable.
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
View view = convertView;
if (view == null) {
LayoutInflater inflater = (LayoutInflater)getActivity().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.custom_listview, null);
}
//Handle TextView and display string from your list
TextView listItemText = (TextView)view.findViewById(R.id.list_item_string);
listItemText.setText(list.get(position));
//Handle buttons and add onClickListeners
Button deleteBtn = (Button)view.findViewById(R.id.delete_btn);
deleteBtn.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
//do something
list.remove(position); //or some other task
notifyDataSetChanged();
}
});
return view;
}
}

Change this line
LayoutInflater inflater = (LayoutInflater)getActivity().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
To this
LayoutInflater inflater = LayoutInflater.from(parent.getContext());

onClickListener on a button that is added through a layout inflator

Here is my code so far based on various answers to related questions on SO.
In my Activity
GridView gv = (GridView) findViewById(R.id.gridView1);
MyCustomAdapter mAdapter = new MyCustomAdapter();
mAdapter.addItem("Action1");
mAdapter.addItem("Action2");
mAdapter.addItem("Action3");
gv.setAdapter(mAdapter);
My Adapter
private class MyCustomAdapter extends BaseAdapter {
private ArrayList<String> mData = new ArrayList<String>();
private LayoutInflater mInflater;
public MyCustomAdapter() {
mInflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
public void addItem(final String item) {
mData.add(item);
notifyDataSetChanged();
}
#Override
public int getCount() {
return mData.size();
}
#Override
public String getItem(int position) {
return mData.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
NumericViewHolder holder = new NumericViewHolder();
if (convertView == null) {
convertView = mInflater.inflate(R.layout.horizontalnumberpicker, null);
holder.textView = (TextView)convertView.findViewById(R.id.txtNPTitle);
holder.minus = (Button)convertView.findViewById(R.id.btnMinus);
holder.plus = (Button)convertView.findViewById(R.id.btnPlus);
holder.value = (TextView)convertView.findViewById(R.id.txtNPValue);
holder.minus.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
TextView tv = (TextView) v.findViewById(R.id.txtNPValue);
int value = Integer.parseInt(tv.getText().toString());
Toast.makeText(getApplicationContext(), Integer.toString(value), Toast.LENGTH_SHORT).show();
if (value > 0) {
value = value - 1;
tv.setText(Integer.toString(value));
}
}
});
holder.plus.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
TextView tv = (TextView) v.findViewById(R.id.txtNPValue);
int value = Integer.parseInt(tv.getText().toString()); <--Error is here
Toast.makeText(getApplicationContext(), Integer.toString(value), Toast.LENGTH_SHORT).show();
value = value + 1;
tv.setText(Integer.toString(value));
}
});
convertView.setTag(holder);
} else {
holder = (NumericViewHolder)convertView.getTag();
}
holder.textView.setText(mData.get(position));
return convertView;
}
}
XML - Main_Activity
<?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:id="#+id/rlAddProduct"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<Button
android:id="#+id/btnSaveProduct"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:layout_marginEnd="20dp"
android:layout_marginRight="20dp"
android:layout_marginTop="20dp"
android:text="#string/Save" />
<TextView
android:id="#+id/lblSelectCategory"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/btnSaveProduct"
android:layout_alignBottom="#+id/btnSaveProduct"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginLeft="20dp"
android:layout_marginStart="20dp"
android:text="#string/selectCategory" />
<Spinner
android:id="#+id/spCategory"
android:layout_width="250dp"
android:layout_height="40dp"
android:layout_alignBottom="#+id/lblSelectCategory"
android:layout_marginLeft="33dp"
android:layout_marginStart="33dp"
android:layout_toEndOf="#+id/lblSelectCategory"
android:layout_toRightOf="#+id/lblSelectCategory" />
<GridView
android:id="#+id/gridView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/lblSelectCategory"
android:layout_below="#+id/btnSaveProduct"
android:layout_marginTop="14dp"
android:numColumns="auto_fit" >
</GridView>
</RelativeLayout>
XML - Horizontalnumberpicker
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/RelativeLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="#+id/txtNPTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:text="EnterTextHere"
android:layout_marginTop="5dp" />
<Button
android:id="#+id/btnPlus"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_alignBaseline="#+id/txtNPValue"
android:layout_alignBottom="#+id/txtNPValue"
android:layout_toRightOf="#+id/txtNPValue"
android:text="+" />
<TextView
android:id="#+id/txtNPValue"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_alignTop="#+id/btnMinus"
android:layout_toRightOf="#+id/btnMinus"
android:gravity="center"
android:text="0"
android:textAppearance="#style/AppBaseTheme"
android:textSize="20dp" />
<Button
android:id="#+id/btnMinus"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_alignParentLeft="true"
android:layout_below="#+id/txtNPTitle"
android:layout_marginTop="2dp"
android:text="-" />
</RelativeLayout>
The requirement is that when I press the plus button, I need to increment the value in the corresponding txtNPValue. Similarly with the minus button, I need to decrement the value in the txtNPValue.
The error is
01-31 22:40:10.854: E/AndroidRuntime(32198): java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.CharSequence android.widget.TextView.getText()' on a null object reference
Also I do not know if this is the right way to program such a requirement and would like some pointers.

TextView tv = (TextView) v.findViewById(R.id.txtNPValue);
this will return null pointer exception, as the view that u r getting is of the button or the clicked item..
Use this :-
RelativeLayout rlLayout = (RelativeLayout) v.getParent();
TextView tv = (TextView) rlLayout.findViewById(R.id.txtNPValue);

please remove:
TextView tv = (TextView) v.findViewById(R.id.txtNPValue);
from onClick to resolve nullpointerException