SearchSuggestionsProvider.java

package org.openintents.filemanager.search;

import java.util.ArrayList;

import android.app.SearchManager;
import android.content.ContentProvider;
import android.content.ContentUris;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.MatrixCursor;
import android.net.Uri;
import android.os.Environment;
import android.provider.BaseColumns;

/**
 * Not that good, but it's a working implementation at least. We REALLY need asynchronous suggestion refreshing.
 * @author George Venios
 *
 */
public class SearchSuggestionsProvider extends ContentProvider {
	public static final String SEARCH_SUGGEST_MIMETYPE = "vnd.android.cursor.item/vnd.openintents.search_suggestion";
	public static final String PROVIDER_NAME = "org.openintents.filemanager.search.suggest";
	public static final Uri CONTENT_URI = Uri.parse("content://" + PROVIDER_NAME);

	private static final long MAX_NANOS = 2000000;
	private static final int MAX_SUGGESTIONS = 7;

	private ArrayList<ContentValues> mSuggestions = new ArrayList<>();
	private SearchCore searcher;

	@Override
	/**
	 * Always clears all suggestions. Parameters other than uri are ignored.
	 */
	public int delete(Uri uri, String selection, String[] selectionArgs) {
		int count = mSuggestions.size();
		mSuggestions.clear();
		getContext().getContentResolver().notifyChange(uri, null);
		
		return count;
	}

	@Override
	public String getType(Uri uri) {
		return SEARCH_SUGGEST_MIMETYPE;
	}

	@Override
	public Uri insert(Uri uri, ContentValues values) {
		long id = mSuggestions.size()+1;
		values.put(BaseColumns._ID, id);
		mSuggestions.add(values);
		
		Uri _uri = ContentUris.withAppendedId(CONTENT_URI, id);
		getContext().getContentResolver().notifyChange(_uri, null);
		
		return _uri;
	}

	@Override
	public boolean onCreate() {
		searcher = new SearchCore(getContext());
		searcher.setMaxResults(MAX_SUGGESTIONS);
		searcher.setURI(CONTENT_URI);
		return true;
	}

	@Override
	/**
	 * NOT a cheap call. Actual search happens here.
	 */
	public Cursor query(Uri uri, String[] projection, String selection,
			String[] selectionArgs, String sortOrder) {
		searcher.setQuery(uri.getLastPathSegment().toLowerCase());
		
		searcher.dropPreviousResults();
		
		searcher.startClock(MAX_NANOS);
		searcher.search(Environment.getExternalStorageDirectory());
		
		MatrixCursor cursor = new MatrixCursor(new String[] {
				SearchManager.SUGGEST_COLUMN_ICON_1,
				SearchManager.SUGGEST_COLUMN_TEXT_1,
				SearchManager.SUGGEST_COLUMN_TEXT_2,
				SearchManager.SUGGEST_COLUMN_INTENT_DATA,
				BaseColumns._ID});
		for (ContentValues val : mSuggestions)
			cursor.newRow().add(val.get(SearchManager.SUGGEST_COLUMN_ICON_1))
					.add(val.get(SearchManager.SUGGEST_COLUMN_TEXT_1))
					.add(val.get(SearchManager.SUGGEST_COLUMN_TEXT_2))
					.add(val.get(SearchManager.SUGGEST_COLUMN_INTENT_DATA))
					.add(val.get(BaseColumns._ID));
		return cursor;
	}

	@Override
	/**
	 * We don't care about updating. Unimplemented.
	 */
	public int update(Uri uri, ContentValues values, String selection,
			String[] selectionArgs) {
		return 0;
	}

}