【发布时间】：2014-10-21 14:12:16
【问题描述】：
请告诉代码有什么问题？任务是在目录中实现搜索。我在当前 MainActivity.java 的清单文件中提到了 SEARCH（它是一个可搜索的活动）。 是否写入数据列表和搜索结果都使用单个活动？
所以我从 Intent 中获取查询，该查询来自使用 LIKE 查询的数据库类：
String sqlQuery1 = "SELECT * FROM city as t1, region as t2 WHERE t1.name LIKE" + "'%" + "?" + "%';";
//Поиск запросом LIKE
public Cursor fetchRecordsByQuery(String query) {
return myDataBase.rawQuery(sqlQuery1, new String[] {query});
}
请您告诉我我做错了什么？正如我所说，任务是实现Android Widget在城市目录中的搜索。我认为问题出在 doMySearch(query);方法。以什么方式以及在哪里放置搜索结果是正确的？
这是MainActivity.java的代码：
package com.example.citycode;
import java.util.concurrent.TimeUnit;
import android.app.SearchManager;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.support.v4.app.LoaderManager.LoaderCallbacks;
import android.support.v4.content.CursorLoader;
import android.support.v4.content.Loader;
import android.support.v4.widget.SimpleCursorAdapter;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.SearchView;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ListView;
public class MainActivity extends ActionBarActivity implements LoaderCallbacks<Cursor> {
ListView lvData;
DBHelper db;
SimpleCursorAdapter scAdapter;
/** Called when the activity is first created. */
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Открываем подключение к БД
db = new DBHelper(this);
db.open();
// Get the intent, verify the action and get the query
Intent intent = getIntent();
if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
String query = intent.getStringExtra(SearchManager.QUERY);
doMySearch(query);
}
// Формируем столбцы сопоставления
String[] from = new String[] { DBHelper.COLUMN_r_name, DBHelper.COLUMN_region, DBHelper.COLUMN_code};
int[] to = new int[] { R.id.city_name, R.id.region_name, R.id.city_code };
// Создаем адаптер и настраиваем список
scAdapter = new SimpleCursorAdapter(this, R.layout.item, null, from, to, 0);
lvData = (ListView) findViewById(R.id.listdata);
lvData.setAdapter(scAdapter);
// Создаем лоадер для чтения данных
getSupportLoaderManager().initLoader(0, null, this);
}
protected void onDestroy() {
super.onDestroy();
// Закрываем подключение к БД при выходе
db.close();
}
public void doMySearch(String query) {
//Ищем совпадения
Cursor cursor1 = db.fetchRecordsByQuery(query);
startManagingCursor(cursor1);
String[] from = new String[] { DBHelper.COLUMN_r_name, DBHelper.COLUMN_region, DBHelper.COLUMN_code};
int[] to = new int[] { R.id.city_name, R.id.region_name, R.id.city_code };
SimpleCursorAdapter records = new SimpleCursorAdapter(this,
R.layout.item, cursor1, from, to);
//Обновляем адаптер
lvData.setAdapter(records);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
// Get the SearchView and set the searchable configuration
SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
SearchView searchView = (SearchView) menu.findItem(R.id.action_settings).getActionView();
// Assumes current activity is the searchable activity
//searchView.setSubmitButtonEnabled(true);
searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
searchView.setIconifiedByDefault(false); // Do not iconify the widget; expand it by default
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
//onSearchRequested();
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public Loader<Cursor> onCreateLoader(int id, Bundle bndl) {
return new MyCursorLoader(this, db);
}
@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {
scAdapter.swapCursor(cursor);
}
@Override
public void onLoaderReset(Loader<Cursor> loader) {
}
static class MyCursorLoader extends CursorLoader {
DBHelper db;
public MyCursorLoader(Context context, DBHelper db) {
super(context);
this.db = db;
}
@Override
public Cursor loadInBackground() {
Cursor cursor = db.getAllData();
try {
TimeUnit.SECONDS.sleep(2);
} catch (InterruptedException e) {
e.printStackTrace();
}
return cursor;
}
}
}
我收到以下错误：
10-21 13:50:03.697: E/AndroidRuntime(12899):
java.lang.RuntimeException:
Unable to start activity ComponentInfo{com.example.citycode/com.example.citycode.MainActivity}:
java.lang.IllegalArgumentException:
Cannot bind argument at index 1 because the index is out of range. The statement has 0 parameters.
我做错了什么？
这是实现更简单的 MainActivity.java 代码，但仍然无法正常工作...
package com.example.citycode;
import android.app.SearchManager;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.SearchView;
import android.view.Menu;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
public class MainActivity extends ActionBarActivity {
ListView lvData;
DBHelper db;
SimpleCursorAdapter scAdapter;
SimpleCursorAdapter records;
Cursor cursor;
Cursor cursor1;
/** Called when the activity is first created. */
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// открываем подключение к БД
db = new DBHelper(this);
db.open();
// Get the intent, verify the action and get the query
Intent intent = getIntent();
if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
String query = intent.getStringExtra(SearchManager.QUERY);
doMySearch(query);
}
// получаем курсор
cursor = db.getAllData();
startManagingCursor(cursor);
// Формируем столбцы сопоставления
String[] from = new String[] { DBHelper.COLUMN_r_name, DBHelper.COLUMN_region, DBHelper.COLUMN_code};
int[] to = new int[] { R.id.city_name, R.id.region_name, R.id.city_code };
// создааем адаптер и настраиваем список
scAdapter = new SimpleCursorAdapter(this, R.layout.item, cursor, from, to);
lvData = (ListView) findViewById(R.id.listdata);
lvData.setAdapter(scAdapter);
}
public void doMySearch(String query) {
//Ищем совпадения
cursor1 = db.fetchRecordsByQuery(query);
startManagingCursor(cursor1);
String[] from = new String[] { DBHelper.COLUMN_r_name, DBHelper.COLUMN_region, DBHelper.COLUMN_code};
int[] to = new int[] { R.id.city_name, R.id.region_name, R.id.city_code };
SimpleCursorAdapter records = new SimpleCursorAdapter(this,
R.layout.item, cursor1, from, to);
//Обновляем адаптер
lvData.setAdapter(records);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.options_main, menu);
// Get the SearchView and set the searchable configuration
SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
SearchView searchView = (SearchView) menu.findItem(R.id.action_settings).getActionView();
// Assumes current activity is the searchable activity
//searchView.setSubmitButtonEnabled(true);
searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
searchView.setIconifiedByDefault(false); // Do not iconify the widget; expand it by default
return true;
}
protected void onDestroy() {
super.onDestroy();
// закрываем подключение при выходе
db.close();
}
}
【问题讨论】：
标签： android sqlite search android-sqlite