Question

我尝试使用searchView过滤Listview，我使用SimpleCursorAdapter填充了listview但是当我点击Searchview栏并没有输入任何过滤器时，这就是我到目前为止所做的。

我的搜索活动

package com.example.androidcontacts;

import java.util.ArrayList;
import android.app.ListActivity;
import android.content.CursorLoader;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.widget.CursorAdapter;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.SearchView;
import android.widget.SearchView.OnQueryTextListener;
import android.widget.SimpleCursorAdapter;

public class Search extends ListActivity {


    ListView listView;
    SearchView searchView;

    ArrayAdapter<String> adapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_search);

        searchView=(SearchView)findViewById(R.id.searchView1);
        listView=(ListView)findViewById(android.R.id.list);

        Uri allContacts = Uri.parse("content://"+"com.example.androidcontacts.Books" + "/Contact");

        Cursor c;
        CursorLoader cursorLoader = new CursorLoader(
        this,allContacts,null,null,null,null);
        c = cursorLoader.loadInBackground();
        // THE DESIRED COLUMNS TO BE BOUND*/
        String[] columns = new String[] {Contact.TITLE};    
        int[] views = new int[] {R.id.code};

        listView.setAdapter(adapter);
    final SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.listview_item_layout, 
                c, columns, views,CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);

        this.setListAdapter(adapter); 



    searchView.setOnQueryTextListener(new OnQueryTextListener(){


            @Override
            public boolean onQueryTextSubmit(String query) {

                    return false;

            }

            @Override
            public boolean onQueryTextChange(String newText) {
                adapter.getFilter().filter(newText);


                return false;
            }

        });
    }

}

我的内容提供商

package com.example.androidcontacts;






import android.content.ContentProvider;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.Context;
import android.content.UriMatcher;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteQueryBuilder;
import android.net.Uri;
import android.text.TextUtils;
import android.util.Log;

public class Contact extends ContentProvider {

    static final String PROVIDER_NAME = "com.example.androidcontacts.Books";
    static final Uri CONTENT_URI = Uri.parse("content://"+ PROVIDER_NAME + "/Contact");
    static final String _ID = "_id";
    static final String TITLE = "title";
    static final String AUTHOR = "author";
    static final String YEAR = "year";
    static final String IMAGE = "image";
    static final int BOOKS = 1;
    static final int BOOK_ID = 2;

    private static final UriMatcher uriMatcher;
    static{
        uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
        uriMatcher.addURI(PROVIDER_NAME, "books", BOOKS);
        uriMatcher.addURI(PROVIDER_NAME, "books/#", BOOK_ID);
    }


    //---for database use---
    DatabaseHelper DBHelper;
    SQLiteDatabase booksDB;
    static final String DATABASE_NAME = "Books";
    static final String DATABASE_TABLE = "Contact";
    static final int DATABASE_VERSION = 1;
    static final String DATABASE_CREATE = "create table " + DATABASE_TABLE +
                " (_id integer primary key autoincrement, " + "title text not null, author text not null, year text not null"
                        + ", image BLOB);";


    private final class DatabaseHelper extends SQLiteOpenHelper
    {

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

        @Override
        public void onCreate(SQLiteDatabase db)
        {
            db.execSQL(DATABASE_CREATE);
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion,int newVersion) {
                Log.w("Content provider database","Upgrading database from version " + oldVersion + " to " + newVersion +
                        ", which will destroy all old data");
                db.execSQL("DROP TABLE IF EXISTS titles");
                onCreate(db);
        }

    }


    @Override
    public int delete(Uri arg0, String arg1, String[] arg2) {
        // arg0 = uri
        // arg1 = selection
        // arg2 = selectionArgs
        int count=0;

        switch (uriMatcher.match(arg0)){
            case BOOKS:
                count = booksDB.delete(DATABASE_TABLE,arg1,arg2);
            break;
            case BOOK_ID:
                String id = arg0.getPathSegments().get(1);
                count = booksDB.delete(DATABASE_TABLE,_ID + " = " + id +
                (!TextUtils.isEmpty(arg1) ? " AND (" + arg1 + ')' : ""),arg2);
            break;
            default: throw new IllegalArgumentException("Unknown URI " + arg0);
        }
        getContext().getContentResolver().notifyChange(arg0, null);
        return count;
    }

    @Override
    public String getType(Uri uri){
        switch (uriMatcher.match(uri)){
            // Get all books
            case BOOKS:
                return "vnd.android.cursor.dir/vnd.androidcontacts.Books ";

            // Get a particular book
            case BOOK_ID:
                return "vnd.android.cursor.item/vnd.androidcontacts.Books ";

            default:
                throw new IllegalArgumentException("Unsupported URI: " + uri);
        }
    }

    @Override
    public Uri insert(Uri uri, ContentValues values) {

        // add a new winner
        long rowID = booksDB.insert(DATABASE_TABLE,"",values);

        // if winner record added successfully
        if (rowID>0)
        {
            Uri _uri = ContentUris.withAppendedId(CONTENT_URI, rowID);
            getContext().getContentResolver().notifyChange(_uri, null);
            return _uri;
        }
        throw new SQLException("Failed to insert row into " + uri);
    }

    @Override
    public boolean onCreate() {
        Context context = getContext();
        DatabaseHelper dbHelper = new DatabaseHelper(context);
        booksDB = dbHelper.getWritableDatabase();
        return (booksDB == null)? false:true;
    }

    @Override
    public Cursor query(Uri uri, String[] projection, String selection,
        String[] selectionArgs, String sortOrder) {
        SQLiteQueryBuilder sqlBuilder = new SQLiteQueryBuilder();
        sqlBuilder.setTables(DATABASE_TABLE);

        if (uriMatcher.match(uri) == BOOK_ID)
            // If getting a particular winner
            sqlBuilder.appendWhere(_ID + " = " + uri.getPathSegments().get(1));

        if (sortOrder==null || sortOrder=="")
            sortOrder = TITLE;

        Cursor c = sqlBuilder.query(booksDB,projection,selection,selectionArgs,
                                null,null,sortOrder);

        // Register to watch a content URI for changes
        c.setNotificationUri(getContext().getContentResolver(), uri);

        return c;
    }

    @Override
    public int update(Uri uri, ContentValues values, String selection,
        String[] selectionArgs) {
        int count = 0;
        switch (uriMatcher.match(uri)){
            case BOOKS:
                count = booksDB.update(DATABASE_TABLE,values,selection,selectionArgs);
                break;
            case BOOK_ID:
                count = booksDB.update(DATABASE_TABLE,values,_ID + " = " + uri.getPathSegments().get(1) +
                        (!TextUtils.isEmpty(selection) ? " AND (" + selection + ')' : ""),selectionArgs);
                break;
            default: throw new IllegalArgumentException("Unknown URI " + uri);
        }
        getContext().getContentResolver().notifyChange(uri, null);
        return count;
    }


}

Answer 1

始终致电＆＃34;通知＆＃34;当数据集发生变化时，适配器的方法会被光标或数组所取代。

adapter.getFilter().filter(newText);
adapter.notifyDatasetChanged();

您也可以仅针对UI更新调用notifyDatasetInvalidated（），而不是针对数据更改调用。但是对于你的问题，你应该尝试第一个。

希望这有帮助。

SearchView过滤器无法正常工作

1 个答案: