伙计们，我正在尝试在我的“可搜索字典”代码示例中添加一个新列（KEY_EXAMPLE）
KEY_EXAMPLE应该是第三列。但它不起作用......
这是我的代码：
DictionaryDatabase.Java
public class DictionaryDatabase {
private static final String TAG = "DictionaryDatabase";
//The columns we'll include in the dictionary table
public static final String KEY_WORD = SearchManager.SUGGEST_COLUMN_TEXT_1;
public static final String KEY_DEFINITION = SearchManager.SUGGEST_COLUMN_TEXT_2;
public static final String KEY_EXAMPLE = SearchManager.SUGGEST_COLUMN_TEXT_1;
private static final String DATABASE_NAME = "dictionary";
private static final String FTS_VIRTUAL_TABLE = "FTSdictionary";
private static final int DATABASE_VERSION = 2;
private final DictionaryOpenHelper mDatabaseOpenHelper;
private static final HashMap<String,String> mColumnMap = buildColumnMap();
/**
* Constructor
* @param context The Context within which to work, used to create the DB
*/
public DictionaryDatabase(Context context) {
mDatabaseOpenHelper = new DictionaryOpenHelper(context);
}
/**
* Builds a map for all columns that may be requested, which will be given to the
* SQLiteQueryBuilder. This is a good way to define aliases for column names, but must include
* all columns, even if the value is the key. This allows the ContentProvider to request
* columns w/o the need to know real column names and create the alias itself.
*/
private static HashMap<String,String> buildColumnMap() {
HashMap<String,String> map = new HashMap<String,String>();
map.put(KEY_WORD, KEY_WORD);
map.put(KEY_DEFINITION, KEY_DEFINITION);
map.put(KEY_EXAMPLE, KEY_EXAMPLE);
map.put(BaseColumns._ID, "rowid AS " +
BaseColumns._ID);
map.put(SearchManager.SUGGEST_COLUMN_INTENT_DATA_ID, "rowid AS " +
SearchManager.SUGGEST_COLUMN_INTENT_DATA_ID);
map.put(SearchManager.SUGGEST_COLUMN_SHORTCUT_ID, "rowid AS " +
SearchManager.SUGGEST_COLUMN_SHORTCUT_ID);
return map;
}
/**
* Returns a Cursor positioned at the word specified by rowId
*
* @param rowId id of word to retrieve
* @param columns The columns to include, if null then all are included
* @return Cursor positioned to matching word, or null if not found.
*/
public Cursor getWord(String rowId, String[] columns) {
String selection = "rowid = ?";
String[] selectionArgs = new String[] {rowId};
return query(selection, selectionArgs, columns);
/* This builds a query that looks like:
* SELECT <columns> FROM <table> WHERE rowid = <rowId>
*/
}
/**
* Returns a Cursor over all words that match the given query
*
* @param query The string to search for
* @param columns The columns to include, if null then all are included
* @return Cursor over all words that match, or null if none found.
*/
public Cursor getWordMatches(String query, String[] columns) {
String selection = KEY_WORD + " MATCH ?";
String[] selectionArgs = new String[] {query+"*"};
return query(selection, selectionArgs, columns);
/* This builds a query that looks like:
* SELECT <columns> FROM <table> WHERE <KEY_WORD> MATCH 'query*'
* which is an FTS3 search for the query text (plus a wildcard) inside the word column.
*
* - "rowid" is the unique id for all rows but we need this value for the "_id" column in
* order for the Adapters to work, so the columns need to make "_id" an alias for "rowid"
* - "rowid" also needs to be used by the SUGGEST_COLUMN_INTENT_DATA alias in order
* for suggestions to carry the proper intent data.
* These aliases are defined in the DictionaryProvider when queries are made.
* - This can be revised to also search the definition text with FTS3 by changing
* the selection clause to use FTS_VIRTUAL_TABLE instead of KEY_WORD (to search across
* the entire table, but sorting the relevance could be difficult.
*/
}
/**
* Performs a database query.
* @param selection The selection clause
* @param selectionArgs Selection arguments for "?" components in the selection
* @param columns The columns to return
* @return A Cursor over all rows matching the query
*/
private Cursor query(String selection, String[] selectionArgs, String[] columns) {
/* The SQLiteBuilder provides a map for all possible columns requested to
* actual columns in the database, creating a simple column alias mechanism
* by which the ContentProvider does not need to know the real column names
*/
SQLiteQueryBuilder builder = new SQLiteQueryBuilder();
builder.setTables(FTS_VIRTUAL_TABLE);
builder.setProjectionMap(mColumnMap);
Cursor cursor = builder.query(mDatabaseOpenHelper.getReadableDatabase(),
columns, selection, selectionArgs, null, null, null);
if (cursor == null) {
return null;
} else if (!cursor.moveToFirst()) {
cursor.close();
return null;
}
return cursor;
}
/**
* This creates/opens the database.
*/
private static class DictionaryOpenHelper extends SQLiteOpenHelper {
private final Context mHelperContext;
private SQLiteDatabase mDatabase;
/* Note that FTS3 does not support column constraints and thus, you cannot
* declare a primary key. However, "rowid" is automatically used as a unique
* identifier, so when making requests, we will use "_id" as an alias for "rowid"
*/
private static final String FTS_TABLE_CREATE =
"CREATE VIRTUAL TABLE " + FTS_VIRTUAL_TABLE +
" USING fts3 (" +
KEY_WORD + ", " +
KEY_DEFINITION + ", " +
KEY_EXAMPLE + " );";
DictionaryOpenHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
mHelperContext = context;
}
@Override
public void onCreate(SQLiteDatabase db) {
mDatabase = db;
mDatabase.execSQL(FTS_TABLE_CREATE);
loadDictionary();
}
/**
* Starts a thread to load the database table with words
*/
private void loadDictionary() {
new Thread(new Runnable() {
public void run() {
try {
loadWords();
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}).start();
}
private void loadWords() throws IOException {
Log.d(TAG, "Loading words...");
final Resources resources = mHelperContext.getResources();
InputStream inputStream = resources.openRawResource(R.raw.definitions);
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
try {
String line;
while ((line = reader.readLine()) != null) {
String[] strings = TextUtils.split(line, "//");
if (strings.length < 2) continue;
long id = addWord(strings[0].trim(), strings[1].trim(), strings[2].trim());
if (id < 0) {
Log.e(TAG, "unable to add word: " + strings[0].trim());
}
}
} finally {
reader.close();
}
Log.d(TAG, "DONE loading words.");
}
/**
* Add a word to the dictionary.
* @return rowId or -1 if failed
*/
public long addWord(String word, String definition, String example) {
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_WORD, word);
initialValues.put(KEY_DEFINITION, definition);
initialValues.put(KEY_EXAMPLE, example);
return mDatabase.insert(FTS_VIRTUAL_TABLE, null, initialValues);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS " + FTS_VIRTUAL_TABLE);
onCreate(db);
}
}
}
DictionaryProvider.java
public class DictionaryProvider extends ContentProvider {
String TAG = "DictionaryProvider";
public static String AUTHORITY = "com.example.android.searchabledict.DictionaryProvider";
public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/dictionary");
// MIME types used for searching words or looking up a single definition
public static final String WORDS_MIME_TYPE = ContentResolver.CURSOR_DIR_BASE_TYPE +
"/vnd.example.android.searchabledict";
public static final String DEFINITION_MIME_TYPE = ContentResolver.CURSOR_ITEM_BASE_TYPE +
"/vnd.example.android.searchabledict";
private DictionaryDatabase mDictionary;
// UriMatcher stuff
private static final int SEARCH_WORDS = 0;
private static final int GET_WORD = 1;
private static final int SEARCH_SUGGEST = 2;
private static final int REFRESH_SHORTCUT = 3;
private static final UriMatcher sURIMatcher = buildUriMatcher();
/**
* Builds up a UriMatcher for search suggestion and shortcut refresh queries.
*/
private static UriMatcher buildUriMatcher() {
UriMatcher matcher = new UriMatcher(UriMatcher.NO_MATCH);
// to get definitions...
matcher.addURI(AUTHORITY, "dictionary", SEARCH_WORDS);
matcher.addURI(AUTHORITY, "dictionary/#", GET_WORD);
// to get suggestions...
matcher.addURI(AUTHORITY, SearchManager.SUGGEST_URI_PATH_QUERY, SEARCH_SUGGEST);
matcher.addURI(AUTHORITY, SearchManager.SUGGEST_URI_PATH_QUERY + "/*", SEARCH_SUGGEST);
/* The following are unused in this implementation, but if we include
* {@link SearchManager#SUGGEST_COLUMN_SHORTCUT_ID} as a column in our suggestions table, we
* could expect to receive refresh queries when a shortcutted suggestion is displayed in
* Quick Search Box, in which case, the following Uris would be provided and we
* would return a cursor with a single item representing the refreshed suggestion data.
*/
matcher.addURI(AUTHORITY, SearchManager.SUGGEST_URI_PATH_SHORTCUT, REFRESH_SHORTCUT);
matcher.addURI(AUTHORITY, SearchManager.SUGGEST_URI_PATH_SHORTCUT + "/*", REFRESH_SHORTCUT);
return matcher;
}
@Override
public boolean onCreate() {
mDictionary = new DictionaryDatabase(getContext());
return true;
}
/**
* Handles all the dictionary searches and suggestion queries from the Search Manager.
* When requesting a specific word, the uri alone is required.
* When searching all of the dictionary for matches, the selectionArgs argument must carry
* the search query as the first element.
* All other arguments are ignored.
*/
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
String sortOrder) {
// Use the UriMatcher to see what kind of query we have and format the db query accordingly
switch (sURIMatcher.match(uri)) {
case SEARCH_SUGGEST:
if (selectionArgs == null) {
throw new IllegalArgumentException(
"selectionArgs must be provided for the Uri: " + uri);
}
return getSuggestions(selectionArgs[0]);
case SEARCH_WORDS:
if (selectionArgs == null) {
throw new IllegalArgumentException(
"selectionArgs must be provided for the Uri: " + uri);
}
return search(selectionArgs[0]);
case GET_WORD:
return getWord(uri);
case REFRESH_SHORTCUT:
return refreshShortcut(uri);
default:
throw new IllegalArgumentException("Unknown Uri: " + uri);
}
}
private Cursor getSuggestions(String query) {
query = query.toLowerCase();
String[] columns = new String[] {
BaseColumns._ID,
DictionaryDatabase.KEY_WORD,
/* SearchManager.SUGGEST_COLUMN_SHORTCUT_ID,
(only if you want to refresh shortcuts) */
SearchManager.SUGGEST_COLUMN_INTENT_DATA_ID};
return mDictionary.getWordMatches(query, columns);
}
private Cursor search(String query) {
query = query.toLowerCase();
String[] columns = new String[] {
BaseColumns._ID,
DictionaryDatabase.KEY_WORD,
DictionaryDatabase.KEY_DEFINITION,
DictionaryDatabase.KEY_EXAMPLE};
return mDictionary.getWordMatches(query, columns);
}
private Cursor getWord(Uri uri) {
String rowId = uri.getLastPathSegment();
String[] columns = new String[] {
DictionaryDatabase.KEY_WORD,
DictionaryDatabase.KEY_DEFINITION,
DictionaryDatabase.KEY_EXAMPLE};
return mDictionary.getWord(rowId, columns);
}
private Cursor refreshShortcut(Uri uri) {
/* This won't be called with the current implementation, but if we include
* {@link SearchManager#SUGGEST_COLUMN_SHORTCUT_ID} as a column in our suggestions table, we
* could expect to receive refresh queries when a shortcutted suggestion is displayed in
* Quick Search Box. In which case, this method will query the table for the specific
* word, using the given item Uri and provide all the columns originally provided with the
* suggestion query.
*/
String rowId = uri.getLastPathSegment();
String[] columns = new String[] {
BaseColumns._ID,
DictionaryDatabase.KEY_WORD,
DictionaryDatabase.KEY_DEFINITION,
DictionaryDatabase.KEY_EXAMPLE,
SearchManager.SUGGEST_COLUMN_SHORTCUT_ID,
SearchManager.SUGGEST_COLUMN_INTENT_DATA_ID};
return mDictionary.getWord(rowId, columns);
}
/**
* This method is required in order to query the supported types.
* It's also useful in our own query() method to determine the type of Uri received.
*/
@Override
public String getType(Uri uri) {
switch (sURIMatcher.match(uri)) {
case SEARCH_WORDS:
return WORDS_MIME_TYPE;
case GET_WORD:
return DEFINITION_MIME_TYPE;
case SEARCH_SUGGEST:
return SearchManager.SUGGEST_MIME_TYPE;
case REFRESH_SHORTCUT:
return SearchManager.SHORTCUT_MIME_TYPE;
default:
throw new IllegalArgumentException("Unknown URL " + uri);
}
}
// Other required implementations...
@Override
public Uri insert(Uri uri, ContentValues values) {
throw new UnsupportedOperationException();
}
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
throw new UnsupportedOperationException();
}
@Override
public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
throw new UnsupportedOperationException();
}
}
SearchableDictionary.java
public class SearchableDictionary extends Activity {
private TextView mTextView;
private ListView mListView;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mTextView = (TextView) findViewById(R.id.text);
mListView = (ListView) findViewById(R.id.list);
handleIntent(getIntent());
}
@Override
protected void onNewIntent(Intent intent) {
// Because this activity has set launchMode="singleTop", the system calls this method
// to deliver the intent if this activity is currently the foreground activity when
// invoked again (when the user executes a search from this activity, we don't create
// a new instance of this activity, so the system delivers the search intent here)
handleIntent(intent);
}
private void handleIntent(Intent intent) {
if (Intent.ACTION_VIEW.equals(intent.getAction())) {
// handles a click on a search suggestion; launches activity to show word
Intent wordIntent = new Intent(this, WordActivity.class);
wordIntent.setData(intent.getData());
startActivity(wordIntent);
} else if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
// handles a search query
String query = intent.getStringExtra(SearchManager.QUERY);
showResults(query);
}
}
/**
* Searches the dictionary and displays results for the given query.
* @param query The search query
*/
private void showResults(String query) {
Cursor cursor = managedQuery(DictionaryProvider.CONTENT_URI, null, null,
new String[] {query}, null);
if (cursor == null) {
// There are no results
mTextView.setText(getString(R.string.no_results, new Object[] {query}));
} else {
// Display the number of results
int count = cursor.getCount();
String countString = getResources().getQuantityString(R.plurals.search_results,
count, new Object[] {count, query});
mTextView.setText(countString);
// Specify the columns we want to display in the result
String[] from = new String[] { DictionaryDatabase.KEY_WORD,
DictionaryDatabase.KEY_DEFINITION,
DictionaryDatabase.KEY_EXAMPLE};
// Specify the corresponding layout elements where we want the columns to go
int[] to = new int[] { R.id.word,
R.id.definition,
R.id.example};
// Create a simple cursor adapter for the definitions and apply them to the ListView
SimpleCursorAdapter words = new SimpleCursorAdapter(this,
R.layout.result, cursor, from, to);
mListView.setAdapter(words);
// Define the on-click listener for the list items
mListView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
// Build the Intent used to open WordActivity with a specific word Uri
Intent wordIntent = new Intent(getApplicationContext(), WordActivity.class);
Uri data = Uri.withAppendedPath(DictionaryProvider.CONTENT_URI,
String.valueOf(id));
wordIntent.setData(data);
startActivity(wordIntent);
}
});
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.options_menu, menu);
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB){
SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
SearchView searchView = (SearchView) menu.findItem(R.id.search).getActionView();
searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
searchView.setIconifiedByDefault(false);
}
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.search:
onSearchRequested();
return true;
default:
return false;
}
}
}
WordActivity.java
public class WordActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.word);
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB){
ActionBar actionBar = getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
}
Uri uri = getIntent().getData();
Cursor cursor = managedQuery(uri, null, null, null, null);
if (cursor == null) {
finish();
} else {
cursor.moveToFirst();
TextView word = (TextView) findViewById(R.id.word);
TextView definition = (TextView) findViewById(R.id.definition);
TextView example = (TextView) findViewById(R.id.example);
int wIndex = cursor.getColumnIndexOrThrow(DictionaryDatabase.KEY_WORD);
int dIndex = cursor.getColumnIndexOrThrow(DictionaryDatabase.KEY_DEFINITION);
int eIndex = cursor.getColumnIndexOrThrow(DictionaryDatabase.KEY_EXAMPLE);
word.setText(cursor.getString(wIndex));
definition.setText(cursor.getString(dIndex));
example.setText(cursor.getString(eIndex));
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.options_menu, menu);
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB){
SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
SearchView searchView = (SearchView) menu.findItem(R.id.search).getActionView();
searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
searchView.setIconifiedByDefault(false);
}
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.search:
onSearchRequested();
return true;
case android.R.id.home:
Intent intent = new Intent(this, SearchableDictionary.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
return true;
default:
return false;
}
}
}
答案 0 :(得分：0)
关闭检查显示您具有分配给1和3的相同字符串值
public static final String KEY_WORD = SearchManager.SUGGEST_COLUMN_TEXT_1;
public static final String KEY_DEFINITION = SearchManager.SUGGEST_COLUMN_TEXT_2;
public static final String KEY_EXAMPLE = SearchManager.SUGGEST_COLUMN_TEXT_1;
答案 1 :(得分：0)
这是一个限制，你在android
提供的搜索建议中只能有两个项目参考
部分http://www.grokkingandroid.com/android-tutorial-adding-suggestions-to-search/ 中的搜索建议的最大问题