imageView.setImageResource is null in recycleView-CodePudding

I am trying to create a recycleView with image and toolbar. this is my adapter

public class ImageAdabter extends RecyclerView.Adapter<ImageViewHolder> {

private Context mContext;
private List<Integer> listImages;

public ImageAdabter(Context mContext) {
    this.mContext = mContext;
    this.listImages=getImages();
}

private List<Integer> getImages() {
    List<Integer> results = new ArrayList<>();
    results.add(R.drawable.ballon);
    results.add(R.drawable.owl);
    results.add(R.drawable.fish);
    return results;
}

@NonNull
@Override
public ImageViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
    View view = LayoutInflater.from(mContext).inflate(R.layout.item_images,parent,false);
    return new ImageViewHolder(view);
}

@Override
public void onBindViewHolder(@NonNull ImageViewHolder holder, int position){holder.imageView.setImageResource(listImages.get(position));
}

@Override
public int getItemCount() {
    return listImages.size();
}

and i create a ImageViewHolder class . this is may code

public class ImageViewHolder extends RecyclerView.ViewHolder {

public ImageView imageView;
public ImageViewHolder(@NonNull View itemView) {
    super(itemView);
    itemView= itemView.findViewById(R.id.image_outline);

}

My main class code is

 initTollbar();
    initView();
}

private void initView() {
    recyclerView = findViewById(R.id.recycle_view_images);
    recyclerView.setHasFixedSize(true);
    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    adabter = new ImageAdabter(this);
    recyclerView.setAdapter(adabter);
}

@RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
private void initTollbar() {
    Toolbar toolbar = findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    int toolbar_item_color= ResourcesCompat.getColor(getResources(),R.color.blue,null);
    toolbar.setTitleTextColor(toolbar_item_color);
    toolbar.setSubtitleTextColor(toolbar_item_color);
    getSupportActionBar().setTitle("Mes Images");
    getSupportActionBar().setDisplayShowHomeEnabled(true);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    getSupportActionBar().setHomeAsUpIndicator(R.drawable.close);
}

@Override
public boolean onOptionsItemSelected(@NonNull MenuItem item) {
    int id = item.getItemId();
    if(id == android.R.id.home){
        finish();
    }
    return super.onOptionsItemSelected(item);
}

when i run my code i got this error

java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ImageView.setImageResource(int)' on a null object reference .adabters.ImageAdabter.onBindViewHolder(ImageAdabter.java:44) .adabters.ImageAdabter.onBindViewHolder(ImageAdabter.java:17)

thanks

CodePudding user response：

Use below code

public class ImageViewHolder extends RecyclerView.ViewHolder {

public ImageView imageView;
public ImageViewHolder(@NonNull View itemView) {
    super(itemView);
    imageView = itemView.findViewById(R.id.image_outline);

}