The file containing the source code shown below is located in the corresponding directory in <sdk>/samples/android-<version>/...
/*
* Copyright (C) 2010 The Android开源工程
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.searchabledict;
import android.app.SearchManager;
import android.content.ContentProvider;
import android.content.ContentResolver;
import android.content.ContentValues;
import android.content.UriMatcher;
import android.database.Cursor;
import android.net.Uri;
import android.provider.BaseColumns;
/**
* Provides access to the dictionary database.
*/
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,
DictionaryDatabase.KEY_DEFINITION,
/* 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};
return mDictionary.getWordMatches(query, columns);
}
private Cursor getWord(Uri uri) {
String rowId = uri.getLastPathSegment();
String[] columns = new String[] {
DictionaryDatabase.KEY_WORD,
DictionaryDatabase.KEY_DEFINITION};
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,
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();
}
}