我的应用程序的Recycler View问题中的Android Studio SearchView过滤器

Question

/ *创建，读取，写入，更新和删除功能有效，但是当我尝试添加过滤器recyclerView的searchview我的应用程序关闭时，我知道一定缺少某些东西，例如依赖项，还检查了清单，但是可以肯定问题是执行搜索过滤器的代码（注释块这是我尝试在VIewlist活动中执行搜索过滤器的代码）

**The inputs are saved using sqlite, thanks guys

这里是logcat

enter image description here

这里是logcat2

enter image description here继承人的代码

The main activity just directs the user in/ Onclick listener to add record activity and view list activity using buttons*/


////////////////////////////////////////////PersonDbHelper/////////////////////////////////////////////////


package info.codestart.glinogaprdrecrds.Utils;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.widget.Toast;

import java.util.LinkedList;
import java.util.List;

import info.codestart.glinogaprdrecrds.model.Person;


public class PersonDBHelper extends SQLiteOpenHelper {

    public static final String DATABASE_NAME = "people.db";
    private static final int DATABASE_VERSION = 3 ;
    public static final String TABLE_NAME = "People";
    public static final String COLUMN_ID = "_id";
    public static final String COLUMN_PERSON_NAME = "name";
    public static final String COLUMN_PERSON_AGE = "age";
    public static final String COLUMN_PERSON_DATE = "date";
    public static final String COLUMN_PERSON_ADDRESS = "address";
    public static final String COLUMN_PERSON_NUMBER = "number";
    public static final String COLUMN_PERSON_LEFT = "lft";
    public static final String COLUMN_PERSON_RIGHT = "rght";
    public static final String COLUMN_PERSON_PAYMENT = "payment";


    public PersonDBHelper(Context context) {
        super(context, DATABASE_NAME , null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(" CREATE TABLE " + TABLE_NAME + " (" +
                COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
                COLUMN_PERSON_NAME + " TEXT NOT NULL, " +
                COLUMN_PERSON_AGE + " NUMBER NOT NULL, " + COLUMN_PERSON_DATE + " TEXT NOT NULL, " +
                COLUMN_PERSON_ADDRESS + " TEXT NOT NULL, " + COLUMN_PERSON_NUMBER + " NUMBER NOT NULL, " +
                COLUMN_PERSON_LEFT + " TEXT NOT NULL, " + COLUMN_PERSON_RIGHT + " TEXT NOT NULL, " +
                COLUMN_PERSON_PAYMENT + " TEXT NOT NULL);"
        );

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // you can implement here migration process
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
        this.onCreate(db);
    }
    /**create record**/
    public void saveNewPerson(Person person) {

        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues values = new ContentValues();
        values.put(COLUMN_PERSON_NAME, person.getName());
        values.put(COLUMN_PERSON_AGE, person.getAge());
        values.put(COLUMN_PERSON_DATE, person.getDate());
        values.put(COLUMN_PERSON_ADDRESS, person.getAddress());
        values.put(COLUMN_PERSON_NUMBER, person.getContactnumber());
        values.put(COLUMN_PERSON_LEFT, person.getLefteyegrade());
        values.put(COLUMN_PERSON_RIGHT, person.getRighteyegrade());
        values.put(COLUMN_PERSON_PAYMENT, person.getPayment());
        // insert
        db.insert(TABLE_NAME,null, values);
        db.close();
    }

    /**Query records, give options to filter results**/
    public List<Person> peopleList(String filter) {
        String query;
        if(filter.equals("")){
            //regular query
            query = "SELECT  * FROM " + TABLE_NAME;
        }else{
            //filter results by filter option provided
            query = "SELECT  * FROM " + TABLE_NAME + " ORDER BY "+ filter;
        }

        List<Person> personLinkedList = new LinkedList<>();
        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(query, null);
        Person person;

        if (cursor.moveToFirst()) {
            do {
                person = new Person();

                person.setId(cursor.getLong(cursor.getColumnIndex(COLUMN_ID)));
                person.setName(cursor.getString(cursor.getColumnIndex(COLUMN_PERSON_NAME)));
                person.setAge(cursor.getString(cursor.getColumnIndex(COLUMN_PERSON_AGE)));
                person.setDate(cursor.getString(cursor.getColumnIndex(COLUMN_PERSON_DATE)));

                personLinkedList.add(person);
            } while (cursor.moveToNext());
        }


        return personLinkedList;
    }

    /**Query only 1 record**/
    public Person getPerson(long id){
        SQLiteDatabase db = this.getWritableDatabase();
        String query = "SELECT  * FROM " + TABLE_NAME + " WHERE _id="+ id;
        Cursor cursor = db.rawQuery(query, null);

        Person receivedPerson = new Person();
        if(cursor.getCount() > 0) {
            cursor.moveToFirst();

            receivedPerson.setName(cursor.getString(cursor.getColumnIndex(COLUMN_PERSON_NAME)));
            receivedPerson.setAge(cursor.getString(cursor.getColumnIndex(COLUMN_PERSON_AGE)));
            receivedPerson.setDate(cursor.getString(cursor.getColumnIndex(COLUMN_PERSON_DATE)));
            receivedPerson.setAddress(cursor.getString(cursor.getColumnIndex(COLUMN_PERSON_ADDRESS)));
            receivedPerson.setContactnumber(cursor.getString(cursor.getColumnIndex(COLUMN_PERSON_NUMBER)));
            receivedPerson.setLefteyegrade(cursor.getString(cursor.getColumnIndex(COLUMN_PERSON_LEFT)));
            receivedPerson.setRighteyegrade(cursor.getString(cursor.getColumnIndex(COLUMN_PERSON_RIGHT)));
            receivedPerson.setPayment(cursor.getString(cursor.getColumnIndex(COLUMN_PERSON_PAYMENT)));

        }
        return receivedPerson;
    }


    /**delete record**/
    public void deletePersonRecord(long id, Context context) {
        SQLiteDatabase db = this.getWritableDatabase();

        db.execSQL("DELETE FROM "+TABLE_NAME+" WHERE _id='"+id+"'");
        Toast.makeText(context, "Deleted successfully.", Toast.LENGTH_SHORT).show();

    }

    /**update record**/
    public void updatePersonRecord(long personId, Context context, Person updatedperson) {
        SQLiteDatabase db = this.getWritableDatabase();
        //you can use the constants above instead of typing the column names
        db.execSQL("UPDATE  "+TABLE_NAME+" SET name ='"+ updatedperson.getName() + "', age ='" + updatedperson.getAge()+ "', date ='"+ updatedperson.getDate() + "', address ='"+ updatedperson.getAddress()+ "', number ='"+ updatedperson.getContactnumber()+ "', lft ='"+ updatedperson.getLefteyegrade()+ "', rght ='"+ updatedperson.getRighteyegrade()+ "', payment ='"+ updatedperson.getPayment()+ "'  WHERE _id='" + personId + "'");
        Toast.makeText(context, "Updated successfully.", Toast.LENGTH_SHORT).show();


    }




}


////////////////////////////////////////////////Person Adapter////////////////////////////////////////////////

package info.glinogaprdrecrds.recrdapp.Utils;

import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

import info.codestart.glinogaprdrecrds.R;
import info.codestart.glinogaprdrecrds.UpdateRecordActivity;
import info.codestart.glinogaprdrecrds.Utils.PersonDBHelper;
import info.codestart.glinogaprdrecrds.model.Person;

public class PersonAdapter extends RecyclerView.Adapter<PersonAdapter.ViewHolder> implements Filterable {

    private List<Person> mPeopleList;
    private List<Person> exampleListFull;
    private Context mContext;
    private RecyclerView mRecyclerV;


    // Provide a reference to the views for each data item
    // Complex data items may need more than one view per item, and
    // you provide access to all the views for a data item in a view holder


    public class ViewHolder extends RecyclerView.ViewHolder {
        // each data item is just a string in this case
        public TextView personNameTxtV;
        public TextView personAgeTxtV;
        public TextView personDateTxtV;



        public View layout;

        public ViewHolder(View v) {
            super(v);
            layout = v;
            personNameTxtV = (TextView) v.findViewById(R.id.name);
            personAgeTxtV = (TextView) v.findViewById(R.id.age);
            personDateTxtV = (TextView) v.findViewById(R.id.date);

        }


    }

        public PersonAdapter(List<Person> mPeopleList){
        this.mPeopleList = mPeopleList;
        exampleListFull = new ArrayList<>(mPeopleList);
    }

    public void add(int position, Person person) {
        mPeopleList.add(position, person);
        notifyItemInserted(position);
    }

    public void remove(int position) {
        mPeopleList.remove(position);
        notifyItemRemoved(position);
    }



    // Provide a suitable constructor (depends on the kind of dataset)
    public PersonAdapter(List<Person> myDataset, Context context, RecyclerView recyclerView) {
        mPeopleList = myDataset;
        mContext = context;
        mRecyclerV = recyclerView;
    }

    // Create new views (invoked by the layout manager)
    @Override
    public PersonAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
                                                   int viewType) {
        // create a new view
        LayoutInflater inflater = LayoutInflater.from(
                parent.getContext());
        View v =
                inflater.inflate(R.layout.single_row, parent, false);
        // set the view's size, margins, paddings and layout parameters
        ViewHolder vh = new ViewHolder(v);
        return vh;
    }

    // Replace the contents of a view (invoked by the layout manager)
    @Override
    public void onBindViewHolder(ViewHolder holder, final int position) {
        // - get element from your dataset at this position
        // - replace the contents of the view with that element

        final Person person = mPeopleList.get(position);
        holder.personNameTxtV.setText("Name: " + person.getName());
        holder.personAgeTxtV.setText("Age: " + person.getAge());
        holder.personDateTxtV.setText("Date: " + person.getDate());

        //listen to single view layout click
        holder.layout.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                AlertDialog.Builder builder = new AlertDialog.Builder(mContext);
                builder.setTitle("Choose option");
                builder.setMessage("Update or delete user?");
                builder.setPositiveButton("Update", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {

                    //go to update activity
                        goToUpdateActivity(person.getId());

                    }
                });
                builder.setNeutralButton("Delete", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        PersonDBHelper dbHelper = new PersonDBHelper(mContext);
                        dbHelper.deletePersonRecord(person.getId(), mContext);

                        mPeopleList.remove(position);
                        mRecyclerV.removeViewAt(position);
                        notifyItemRemoved(position);
                        notifyItemRangeChanged(position, mPeopleList.size());
                        notifyDataSetChanged();
                    }
                });
                builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.dismiss();
                    }
                });
                builder.create().show();
            }
        });


    }

    private void goToUpdateActivity(long personId){
        Intent goToUpdate = new Intent(mContext, UpdateRecordActivity.class);
        goToUpdate.putExtra("USER_ID", personId);
        mContext.startActivity(goToUpdate);
    }

    // Return the size of your dataset (invoked by the layout manager)
    @Override
    public int getItemCount() {
        return mPeopleList.size();
    }

    @Override
    public Filter getFilter(){
        return exampleFilter;
    }

    private Filter exampleFilter = new Filter() {
        @Override
        protected FilterResults performFiltering(CharSequence charSequence) {
            List<Person> filteredList = new ArrayList<>();

            if(charSequence == null || charSequence.length()==0){
                filteredList.addAll(exampleListFull);
            }else{
                String filterPatern = charSequence.toString().toLowerCase().trim();
                for (Person item : exampleListFull){
                    if(item.getName().toLowerCase().contains(filterPatern)){
                        filteredList.add(item);
                    }
                }
            }
            FilterResults results = new FilterResults();
            results.values = filteredList;

            return  results;
        }

        @Override
        protected void publishResults(CharSequence charSequence, FilterResults filterResults) {
            mPeopleList.clear();
            mPeopleList.addAll((List)filterResults.values);
            notifyDataSetChanged();
        }
    };
}


//////////////////////////////////////////////ViewList////////////////////////////////////////////////

package info.codestart.glinogaprdrecrds;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.widget.SearchView;

import java.util.List;

import info.codestart.glinogaprdrecrds.Utils.PersonDBHelper;
import info.codestart.glinogaprdrecrds.model.Person;
import info.glinogaprdrecrds.recrdapp.Utils.PersonAdapter;

public class viewList extends AppCompatActivity {


    private RecyclerView mRecyclerView;
    private RecyclerView.LayoutManager mLayoutManager;
    private PersonDBHelper dbHelper;
    private PersonAdapter adapter;
    private String filter = "";
    private List<Person> exampleList;
    private SearchView searchView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_view_list);


        //initialize the variables
        mRecyclerView = (RecyclerView)findViewById(R.id.recyclerView);
        mRecyclerView.setHasFixedSize(true);
        // use a linear layout manager
        mLayoutManager = new LinearLayoutManager(this);
        mRecyclerView.setLayoutManager(mLayoutManager);
        populaterecyclerView(filter);


    }

    private void populaterecyclerView(String filter){
        dbHelper = new PersonDBHelper(this);
        adapter = new PersonAdapter(dbHelper.peopleList(filter), this, mRecyclerView);
        mRecyclerView.setAdapter(adapter);
    }

    @Override
    protected void onResume() {
        super.onResume();
        adapter.notifyDataSetChanged();
    }

    /*
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.example_menu, menu);

        MenuItem searchItem = menu.findItem(R.id.action_search);
        SearchView searchView = (SearchView) searchItem.getActionView();

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

            @Override
            public boolean onQueryTextChange(String newText) {
                adapter.getFilter().filter(newText);
                return false;
            }
        });
        return true;

    }

     */
}

///////////////////////////////////////////////UpdateRecordActivity//////////////////////////////////////


package info.codestart.glinogaprdrecrds;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import info.codestart.glinogaprdrecrds.Utils.PersonDBHelper;
import info.codestart.glinogaprdrecrds.model.Person;

public class UpdateRecordActivity extends AppCompatActivity {

    private EditText mNameEditText;
    private EditText mAgeEditText;
    private EditText mAddressEditText;
    private EditText mDateEditText;
    private EditText mContactNumberText;
    private EditText mLeftEyeGradeEditText;
    private EditText mRightEyeGradeEditText;
    private EditText mPaymentEditText;
    private Button UpdateUser;

    private PersonDBHelper dbHelper;
    private long receivedPersonId;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_update_record);

        mNameEditText = findViewById(R.id.userNameUpdate);
        mAgeEditText = findViewById(R.id.userAgeUpdate);
        mAddressEditText = findViewById(R.id.userAddressUpdate);
        mDateEditText = findViewById(R.id.userDateUpdate);
        mContactNumberText = findViewById(R.id.userContactNumberUpdate);
        mLeftEyeGradeEditText = findViewById(R.id.userLeftEyeGradeUpdate);
        mRightEyeGradeEditText = findViewById(R.id.userRightEyeGradeUpdate);
        mPaymentEditText = findViewById(R.id.userPaymentUpdate);
        UpdateUser = findViewById(R.id.UpdateUser);

        dbHelper = new PersonDBHelper(this);



        try {
            //get intent to get person id
            receivedPersonId = getIntent().getLongExtra("USER_ID", 1);
        } catch (Exception e) {
            e.printStackTrace();
        }

        /***populate user data before update***/
        Person queriedPerson = dbHelper.getPerson(receivedPersonId);
        //set field to this user data
        mNameEditText.setText(queriedPerson.getName());
        mAgeEditText.setText(queriedPerson.getAge());
        mAddressEditText.setText(queriedPerson.getAddress());
        mDateEditText.setText(queriedPerson.getDate());
        mContactNumberText.setText(queriedPerson.getContactnumber());
        mLeftEyeGradeEditText.setText(queriedPerson.getLefteyegrade());
        mRightEyeGradeEditText.setText(queriedPerson.getRighteyegrade());
        mPaymentEditText.setText(queriedPerson.getPayment());




        //listen to add button click to update
        UpdateUser.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                //call the save person method
                updateUser();
            }
        });

    }

    private void updateUser(){

        String name = mNameEditText.getText().toString().trim();
        String age = mAgeEditText.getText().toString().trim();
        String address = mAddressEditText.getText().toString().trim();
        String date = mDateEditText.getText().toString().trim();
        String contactnumber = mContactNumberText.getText().toString().trim();
        String lefteyegrade =  mLeftEyeGradeEditText.getText().toString().trim();
        String righteyegrade = mRightEyeGradeEditText.getText().toString().trim();
        String payment = mPaymentEditText.getText().toString().trim();

        if(name.isEmpty() && age.isEmpty()&& address.isEmpty()&& date.isEmpty()&& contactnumber.isEmpty()&& lefteyegrade.isEmpty()&& righteyegrade.isEmpty()&& payment.isEmpty() ){
            Toast.makeText(this,"You must fill up all fields", Toast.LENGTH_SHORT).show();
        }

        Person updatedPersonRecord = new Person(name, age, address, date, contactnumber, lefteyegrade, righteyegrade, payment);
        dbHelper.updatePersonRecord(receivedPersonId, this, updatedPersonRecord);
        gotolist();
    }

    private void gotolist(){
        startActivity(new Intent(this, info.codestart.glinogaprdrecrds.MainActivity.class));
    }

}   

//I modified this code to add more user inputs and some layout  from the original template that I followed in youtube tutorials

Answer 1

我使用此方法并正常工作...

这是我在recyclerView中的代码

@Override
public Filter getFilter() {
    return filefilter;
}

private Filter filefilter=new Filter() {
    @Override
    protected FilterResults performFiltering(CharSequence charSequence) {
        ArrayList<String> flist=new ArrayList<>();
        if (charSequence==null || charSequence.length()==0){
            flist.addAll(list2);
        }else {
            String filterpattren=charSequence.toString().toLowerCase().trim();
            for (String item : list2) {
                if (item.toLowerCase().contains(filterpattren)) {
                    flist.add(item);
                }
            }



        }
        FilterResults results=new FilterResults();
        results.values=flist;
        return results;
    }

    @Override
    protected void publishResults(CharSequence charSequence, FilterResults filterResults) {
        mlist.clear();
        mlist.addAll((List)filterResults.values);
        notifyDataSetChanged();
    }
};

这是用于在recyclerview构造函数中创建list2的代码
ArrayList<String> mlist=new ArrayList<>();
ArrayList<String> list2=new ArrayList<>();
Context context;



public MylistAdapter2(ArrayList<String> mlist,Context context){
    this.mlist=mlist;
    list2=new ArrayList<>(mlist);
    this.context=context;
}

这是onCreateOptionMenu中的代码，我在recyclerview中调用getfilter方法
    SearchView searchView=(SearchView) searchItem .getActionView();
    searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
        @Override
        public boolean onQueryTextSubmit(String query) {
            return false;
        }

        @Override
        public boolean onQueryTextChange(String newText) {
            ProfileFragment.mylistAdapter2.getFilter().filter(newText);
            return true;
        }
    });