带有recyclerview和onQueryTextChange监听器的搜索栏

Question

我在android中创建了一个searchview。在OnQueryTextListener中使用OnQueryTextChange（）并将getFilter（）添加到适配器并运行应用程序时，应用程序正确打开，但在搜索栏中键入文本时会关闭应用程序并在onQueryTextChange（）附近显示java.lang.NullpointException错误。 请帮助解决我的问题。下面是代码。

MainActivity

公共类MainActivity扩展了AppCompatActivity {

SearchView searchView;
RecyclerView recyclerView;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

   // Toolbar toolbar= new Toolbar(this);
   // setSupportActionBar(toolbar);


    searchView= (SearchView)findViewById(R.id.search);
    recyclerView=(RecyclerView)findViewById(R.id.recycle);

    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    recyclerView.setItemAnimator(new DefaultItemAnimator());

    final MyAdapter myadapter= new MyAdapter(this,getStudents());
    recyclerView.setAdapter(myadapter);

    if(searchView!=null) {


        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
            @Override
            public boolean onQueryTextSubmit(String query) {
                return false;
            }

            @Override
            public boolean onQueryTextChange(String query) {
                myadapter.getFilter().filter(query);

                return false;
            }
        });
    }
}

private ArrayList<Students> getStudents(){

    ArrayList<Students> students=new ArrayList<>();
    Students s= new Students();
    s.setImg(R.drawable.facebook);
    s.setName("Girish");
    s.setPosition("First");
    students.add(s);

    s=new Students();
    s.setImg(R.drawable.instagram);
    s.setName("Sirish");
    s.setPosition("second");
    students.add(s);

    s=new Students();
    s.setImg(R.drawable.twitter);
    s.setName("Harish");
    s.setPosition("Third");
    students.add(s);

    s=new Students();
    s.setImg(R.drawable.youtube);
    s.setName("Manish");
    s.setPosition("fourth");
    students.add(s);

    s=new Students();
    s.setImg(R.drawable.like);
    s.setName("Mahesh");
    s.setPosition("fifth");
    students.add(s);

    s=new Students();
    s.setImg(R.drawable.googleplus);
    s.setName("Raj");
    s.setPosition("Sixth");
    students.add(s);

    s=new Students();
    s.setImg(R.drawable.snapchat);
    s.setName("Ramesh");
    s.setPosition("Seventh");
    students.add(s);

    return students;
}

}

    MyAdapter:
 public class MyAdapter extends RecyclerView.Adapter<MyHolder> implements Filterable{
Context c;
ArrayList<Students> students, filterlist;
CustomFilter filter;

public MyAdapter(Context context, ArrayList<Students> students) {
    this.c=context;
    this.students=students;
    this.filterlist=students;
}

@Override
public MyHolder onCreateViewHolder(ViewGroup parent, int viewType) {

    View v= LayoutInflater.from(parent.getContext()).inflate(R.layout.model,null);

    MyHolder myHolder=new MyHolder(v);
    return myHolder;
}

@Override
public void onBindViewHolder(MyHolder holder, int position) {

    holder.positionTxt.setText(students.get(position).getPosition());
    holder.nameTxt.setText(students.get(position).getName());
    holder.img.setImageResource(students.get(position).getImg());

    holder.setItemClickListener(new ItemClickListener() {
        @Override
        public void onItemClick(View v, int pos) {
            Toast.makeText(c, "item created", Toast.LENGTH_SHORT).show();
        }
    });

}

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

@Override
public Filter getFilter() {
    if(filter==null){
        filter= new CustomFilter(filterlist,this);
    }
    return null;
}

}