Java 搜索功能在android studio中不起作用

我正在尝试创建一个搜索框，它将返回数据库中与用户在搜索栏中所写内容具有相同标记的所有列表，但由于某种原因，当我转到新的意图时，列表将保持不变，显示数据库中的所有列表。有什么帮助吗

这是我的密码：

package com.example.shareandcare;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.media.Image;
import android.net.Uri;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.AutoCompleteTextView;
import android.widget.Button;
import android.widget.CursorAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.lang.reflect.Array;

public class listings extends Activity {

    private Cursor c = null;
    private listingHelperAdapter adapter = new listingHelperAdapter(c);
    private listingHelper helper = new listingHelper(this);
    private ListView list;
    private Button listingsAddListingButton, listingsSearchButton;
    private AutoCompleteTextView listingsSearch;
    private TextView empty = null;
    private String searchStr = null;

    private static final String[] TAGS = new String[] {
            "Sofa", "Table", "Bed", "Storage", "Tool"
    };

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

        empty = (TextView)findViewById(R.id.listings_Empty);
        list = (ListView)findViewById(R.id.listings_List);

        listingsAddListingButton = (Button)findViewById(R.id.listings_Add_Listing_Button);
        listingsSearchButton = (Button)findViewById(R.id.listings_Search_Button);
        listingsSearch = (AutoCompleteTextView)findViewById(R.id.listings_Search);
        c = helper.getAll();
        list.setAdapter(adapter);

        ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1, TAGS);
        listingsSearch.setAdapter(arrayAdapter);

        listingsSearchButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (listingsSearch.getText().toString() != "") {
                    searchStr = listingsSearch.getText().toString();
                    Intent intent = new Intent(listings.this, listings.class);
                    intent.putExtra("search", searchStr);
                    helper.setSearchStat(true);
                    //finish();
                    startActivity(intent);
                } else if (listingsSearch.getText().toString() == null){
                    helper.setSearchStat(false);
                }
            }
        });

        list.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
            @Override
            public boolean onItemLongClick(AdapterView<?> adapterView, View view, int i, long l) {
                helper.delete(String.valueOf(l));
                //helper.resetDatabase();
                Toast.makeText(listings.this, "Deleted", Toast.LENGTH_SHORT).show();
                Intent intent = new Intent(listings.this, listings.class);
                finish();
                startActivity(intent);
                return true;
            }
        });

        list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                c.moveToPosition(i);
                String title = helper.getListingTitle(c);
                Intent intent = new Intent(listings.this, listing.class);
                intent.putExtra("title",title);
                startActivity(intent);
            }
        });

        listingsAddListingButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent i = new Intent(listings.this, addListing.class);
                startActivity(i);
            }
        });

    }

    @Override
    protected void onResume(){
        super.onResume();

        if (c != null) {
            c.close();
        }
        if (helper.getSearchStat() == false) {
            c = helper.getAll();
        } else if (helper.getSearchStat() == true) {
            c = helper.getByTag(getIntent().getStringExtra("search"));
        }


        if (c.getCount() > 0) {
            empty.setVisibility(View.INVISIBLE);
        }
        adapter.swapCursor(c);
    }

    @Override
    protected void onPause(){
        super.onPause();

    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        helper.close();

    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.options, menu);
        return super.onCreateOptionsMenu(menu);
    }
    @Override
    public boolean onOptionsItemSelected (MenuItem item){

        if (item.getItemId()== R.id.log_out) {
            Toast.makeText(this, "Logged out...", Toast.LENGTH_SHORT).show();
            Intent intent;
            intent = new Intent(listings.this, mainActivity.class);
            startActivity(intent);
        }
        return super.onOptionsItemSelected(item);

    }

    class listingHelperAdapter extends CursorAdapter {
        listingHelperAdapter(Cursor c) {
            super(listings.this, c);
        }

        @Override
        public void bindView(View row, Context ctxt, Cursor c) {
            listingHolder holder = (listingHolder) row.getTag();

            holder.populate(c, helper);
        }

        @Override
        public View newView(Context ctxt, Cursor c, ViewGroup parent) {
            LayoutInflater inflater = getLayoutInflater();
            View row = inflater.inflate(R.layout.listingrow, parent, false);
            listingHolder holder = new listingHolder(row);

            row.setTag(holder);
            return (row);
        }
    }

    static class listingHolder {
        private TextView listingTitle, listingTag, listingDescription;
        //private ImageView furnitureImage = null;

        listingHolder (View row){
            listingTitle = (TextView) row.findViewById(R.id.listing_Title);
            listingTag = (TextView) row.findViewById(R.id.listing_Tag);
            listingDescription = (TextView) row.findViewById(R.id.listing_Description);
        }

        void populate (Cursor c,listingHelper helper){
            listingTitle.setText(helper.getListingTitle(c));
            listingTag.setText(helper.getListingTag(c));
            listingDescription.setText(helper.getListingDesciption(c));
        }
    }
}

package com.example.shareandcare;

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


public class listingHelper extends SQLiteOpenHelper {

    private boolean x = false;

    public listingHelper(Context context) {
        super(context, "listing.db", null, 2);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("create table listing(_id integer primary key autoincrement, listingTitle text, listingTag text, listingDescription text, listingDimensionX float, listingDimensionY float, listingDimensionZ float, listingImage text, listingStatus text)");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){
        db.execSQL("drop table if exists listing");
        onCreate(db);
    }

    public Cursor getAll() {
        return (getReadableDatabase().rawQuery("select _id, listingTitle, listingTag, listingDescription, listingDimensionX, listingDimensionY, listingDimensionZ, listingImage from listing order by listingTag", null));
    }

    public Cursor getAllConfirmed() {
        String arg = "1";
        String[] args = {arg};
        return (getReadableDatabase().rawQuery("select _id, listingTitle, listingTag, listingDescription, listingDimensionX, listingDimensionY, listingDimensionZ, listingImage from listing where listingStatus=?", args));
    }

    public Cursor getById(String id) {
        String[] args = {id};

        return (getReadableDatabase().rawQuery("select _id, listingTitle, listingTag, listingDescription, lisitngDimensionX, listingDimensionY, listingDimensionZ, listingImage from listing where _id=?", args));
    }

    public Cursor getByTitle(String title) {
        String[] args = {title};

        return (getReadableDatabase().rawQuery("select _id, listingTitle, listingTag, listingDescription, listingDimensionX, listingDimensionY, listingDimensionZ, listingImage from listing where listingTitle =?", args));
    }

    public Cursor getByTag(String tag) {
        tag = tag.toLowerCase();
        String[] args = {tag};

        return (getReadableDatabase().rawQuery("select _id, listingTitle, listingTag, listingDescription, listingDimensionX, listingDimensionY, listingDimensionZ, listingImage from listing where listingTag =?", args));
    }

    public void setSearchStat(boolean status) {
        x = status;
    }

    public boolean getSearchStat() {
        return x;
    }

    public void updateListingStatus(String title) {
        ContentValues cv = new ContentValues();
        String[] args ={title};

        cv.put("listingStatus", "1");
        getWritableDatabase().update("listing", cv, "listingTitle=?", args);
    }

    public void addListing(String listingTitle, String listingTag, String listingDescription, String listingDimensionX, String listingDimensionY, String listingDimensionZ, String listingImage) {
        ContentValues cv = new ContentValues();

        cv.put("listingTitle", listingTitle);
        cv.put("listingTag", listingTag.toLowerCase());
        cv.put("listingDescription", listingDescription);
        cv.put("listingDimensionX", listingDimensionX);
        cv.put("listingDimensionY", listingDimensionY);
        cv.put("listingDimensionZ", listingDimensionZ);
        cv.put("listingImage", listingImage);

        getWritableDatabase().insert("listing", "listingTitle", cv);
    }

    public void delete(String id) {
        String[] args = {id};
        getWritableDatabase().delete("listing","_id=?", args);
    }

    public String getID(Cursor c) {
        return (c.getString(0));
    }

    public String getListingTitle (Cursor c) {
        return (c.getString(1));
    }

    public String getListingTag (Cursor c) {
        return (c.getString(2));
    }

    public String getListingDesciption (Cursor c) {
        return (c.getString(3));
    }

    public String getListingDimensionX (Cursor c) {
        return (c.getString(4));
    }

    public String getListingDimensionY (Cursor c) {
        return (c.getString(5));
    }

    public String getListingDimensionZ (Cursor c) {
        return (c.getString(6));
    }

    public String getListingImage (Cursor c) {
        return (c.getString(7));
    }

    public void resetDatabase() {
        getWritableDatabase().execSQL("drop table if exists listing");
    }
}