Question

我想在我的应用程序中实现一个搜索方法。我有一个数据库，我想使用快速搜索框在该数据库中搜索。请帮我完成这项任务。

Answer 1

三个文件相关，DataProvider，DataIndex，更改为AndroidManifest。在我的例子中，我想在我的数据库中查找的数据对象是'Locations'数据对象，因此是我的类的名称，但是您可以毫无问题地将它应用于您的逻辑。

LocationProvider.java：

package com.myapp.android.search;

import android.app.SearchManager;
import android.content.ContentProvider;
import android.content.ContentValues;
import android.content.UriMatcher;
import android.content.res.Resources;
import android.database.Cursor;
import android.database.MatrixCursor;
import android.net.Uri;
import android.text.TextUtils;
import android.util.Log;
import com.myapp.android.MyApp;
import com.myapp.android.model.Location;

import java.util.ArrayList;

/**
 * Provides search suggestions for a list of words and their definitions.
 */
public class LocationProvider extends ContentProvider {

    public static String AUTHORITY = "myapp_locations";

    private static final int SEARCH_SUGGEST = 0;
    private static final int SHORTCUT_REFRESH = 1;
    private static final UriMatcher sURIMatcher = buildUriMatcher();

    /**
     * The columns we'll include in our search suggestions.  There are others that could be used
     * to further customize the suggestions, see the docs in {@link SearchManager} for the details
     * on additional columns that are supported.
     */
    private static final String[] COLUMNS = {
            "_id",  // must include this column
            SearchManager.SUGGEST_COLUMN_TEXT_1,
            SearchManager.SUGGEST_COLUMN_TEXT_2,
            SearchManager.SUGGEST_COLUMN_INTENT_DATA,
            };

    /**
     * Sets up a uri matcher for search suggestion and shortcut refresh queries.
     */
    private static UriMatcher buildUriMatcher() {
        UriMatcher matcher =  new UriMatcher(UriMatcher.NO_MATCH);
        matcher.addURI(AUTHORITY, SearchManager.SUGGEST_URI_PATH_QUERY, SEARCH_SUGGEST);
        matcher.addURI(AUTHORITY, SearchManager.SUGGEST_URI_PATH_QUERY + "/*", SEARCH_SUGGEST);
        matcher.addURI(AUTHORITY, SearchManager.SUGGEST_URI_PATH_SHORTCUT, SHORTCUT_REFRESH);
        matcher.addURI(AUTHORITY, SearchManager.SUGGEST_URI_PATH_SHORTCUT + "/*", SHORTCUT_REFRESH);
        return matcher;
    }

    @Override
    public boolean onCreate() {
        Resources resources = getContext().getResources();
       // LocationIndex.getInstance(this.getContext()).ensureLoaded(resources);
        return true;
    }

    @Override
    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
            String sortOrder) {
        if (!TextUtils.isEmpty(selection)) {
            throw new IllegalArgumentException("selection not allowed for " + uri);
        }
        if (selectionArgs != null && selectionArgs.length != 0) {
            throw new IllegalArgumentException("selectionArgs not allowed for " + uri);
        }
        if (!TextUtils.isEmpty(sortOrder)) {
            throw new IllegalArgumentException("sortOrder not allowed for " + uri);
        }
        switch (sURIMatcher.match(uri)) {
            case SEARCH_SUGGEST:
                String query = null;
                if (uri.getPathSegments().size() > 1) {
                    query = uri.getLastPathSegment().toLowerCase();
                }
                return getSuggestions(query, projection);
            case SHORTCUT_REFRESH:
                String shortcutId = null;
                if (uri.getPathSegments().size() > 1) {
                    shortcutId = uri.getLastPathSegment();
                }
                return refreshShortcut(shortcutId, projection);
            default:
                throw new IllegalArgumentException("Unknown URL " + uri);
        }
    }

    private Cursor getSuggestions(String query, String[] projection) {
        String processedQuery = query == null ? "" : query.toLowerCase();
        ArrayList<Location> words = LocationIndex.getInstance().getMatches(processedQuery);
        MatrixCursor cursor = new MatrixCursor(COLUMNS);
        long id = 0;
        for (Location word : words) {
            cursor.addRow(columnValuesOfWord(id++, word));
        }
        return cursor;
    }

    private Object[] columnValuesOfWord(long id, Location loc) {
        return new Object[] {
                id,                       // _id
                loc.getTitle(),           // text1
                loc.getDescription(),     // text2
                loc.getTitle(),           // intent_data (included when clicking on item)
        };
    }

    /**
     * Note: this is unused as is, but if we included
     * {@link SearchManager#SUGGEST_COLUMN_SHORTCUT_ID} as a column in our results, we
     * could expect to receive refresh queries on this uri for the id provided, in which case we
     * would return a cursor with a single item representing the refreshed suggestion data.
     */
    private Cursor refreshShortcut(String shortcutId, String[] projection) {
        return null;
    }

    /**
     * All queries for this provider are for the search suggestion and shortcut refresh mime type.
     */
    public String getType(Uri uri) {
        switch (sURIMatcher.match(uri)) {
            case SEARCH_SUGGEST:
                return SearchManager.SUGGEST_MIME_TYPE;
            case SHORTCUT_REFRESH:
                return SearchManager.SHORTCUT_MIME_TYPE;
            default:
                throw new IllegalArgumentException("Unknown URL " + uri);
        }
    }

    public Uri insert(Uri uri, ContentValues values) {
        throw new UnsupportedOperationException();
    }

    public int delete(Uri uri, String selection, String[] selectionArgs) {
        throw new UnsupportedOperationException();
    }

    public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
        throw new UnsupportedOperationException();
    }
}

LocationIndex.java

package com.myapp.android.search;

import com.myapp.android.model.Location;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.concurrent.ConcurrentHashMap;

public class LocationIndex {

    private boolean mLoaded = false;
    private static final LocationIndex sInstance = new LocationIndex();
    private ArrayList<Location> locations;
    private final ConcurrentHashMap<String, ArrayList<Location>> mDict = new ConcurrentHashMap<String, ArrayList<Location>>();

    public static LocationIndex getInstance() {
        return sInstance;
    }

    public synchronized void loadWords(ArrayList<Location> locations) { //throws IOException, Resources resources
        if (mLoaded) return;
        this.locations = locations;
        for (Iterator<Location> iter=locations.iterator();iter.hasNext();) {            
            Location loc = iter.next();
            if (loc!=null) addLocation(loc);
        }
        mLoaded = true;

    }

    public ArrayList<Location> getMatches(String query) {
        ArrayList<Location> list = mDict.get(query);
        return list == null ? new ArrayList<Location>() : list;
    }

    private void addLocation(Location loc) {
        final int len = loc.getTitle().length();
        for (int i = 0; i < len; i++) {
            final String prefix = loc.getTitle().substring(0, len - i);
            addMatch(prefix, loc);
        }
    }

    private void addMatch(String query, Location loc) {    
        ArrayList<Location> matches = mDict.get(query);
        if (matches == null) {
            matches = new ArrayList<Location>();
            mDict.put(query.toLowerCase(), matches);
        }
        matches.add(loc);
    }

    public ConcurrentHashMap<String, ArrayList<Location>> getmDict() {
        return mDict;
    }
}

的AndroidManifest.xml

将以下内容添加到您的清单......

<!-- Provides search suggestions for words and their definitions. -->
<provider android:name=".search.LocationProvider"
          android:authorities="myapp_locations"
          android:syncable="false"/>

<provider android:name=".content.LocalFileContentProvider"
          android:authorities="com.myapp.android.localfile"
          android:syncable="false"/>

以及要激活搜索活动的意图过滤器（可能全部）：

<intent-filter>
    <action android:name="android.intent.action.SEARCH"/>
    <category android:name="android.intent.category.DEFAULT"/>
</intent-filter>

如何在我的Android应用程序中使用QuickSearchBox？

1 个答案: