1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 package com.android.launcher3.allapps.search;
17 
18 import static com.android.launcher3.allapps.BaseAllAppsAdapter.VIEW_TYPE_EMPTY_SEARCH;
19 import static com.android.launcher3.util.Executors.MAIN_EXECUTOR;
20 
21 import android.content.Context;
22 import android.os.Handler;
23 
24 import androidx.annotation.AnyThread;
25 
26 import com.android.launcher3.LauncherAppState;
27 import com.android.launcher3.allapps.BaseAllAppsAdapter.AdapterItem;
28 import com.android.launcher3.model.data.AppInfo;
29 import com.android.launcher3.search.SearchAlgorithm;
30 import com.android.launcher3.search.SearchCallback;
31 import com.android.launcher3.search.StringMatcherUtility;
32 
33 import java.util.ArrayList;
34 import java.util.List;
35 
36 /**
37  * The default search implementation.
38  */
39 public class DefaultAppSearchAlgorithm implements SearchAlgorithm<AdapterItem> {
40 
41     private static final int MAX_RESULTS_COUNT = 5;
42 
43     private final LauncherAppState mAppState;
44     private final Handler mResultHandler;
45     private final boolean mAddNoResultsMessage;
46 
DefaultAppSearchAlgorithm(Context context)47     public DefaultAppSearchAlgorithm(Context context) {
48         this(context, false);
49     }
50 
DefaultAppSearchAlgorithm(Context context, boolean addNoResultsMessage)51     public DefaultAppSearchAlgorithm(Context context, boolean addNoResultsMessage) {
52         mAppState = LauncherAppState.getInstance(context);
53         mResultHandler = new Handler(MAIN_EXECUTOR.getLooper());
54         mAddNoResultsMessage = addNoResultsMessage;
55     }
56 
57     @Override
cancel(boolean interruptActiveRequests)58     public void cancel(boolean interruptActiveRequests) {
59         if (interruptActiveRequests) {
60             mResultHandler.removeCallbacksAndMessages(null);
61         }
62     }
63 
64     @Override
doSearch(String query, SearchCallback<AdapterItem> callback)65     public void doSearch(String query, SearchCallback<AdapterItem> callback) {
66         mAppState.getModel().enqueueModelUpdateTask((taskController, dataModel, apps) ->  {
67             ArrayList<AdapterItem> result = getTitleMatchResult(apps.data, query);
68             if (mAddNoResultsMessage && result.isEmpty()) {
69                 result.add(getEmptyMessageAdapterItem(query));
70             }
71             mResultHandler.post(() -> callback.onSearchResult(query, result));
72         });
73     }
74 
getEmptyMessageAdapterItem(String query)75     private static AdapterItem getEmptyMessageAdapterItem(String query) {
76         AdapterItem item = new AdapterItem(VIEW_TYPE_EMPTY_SEARCH);
77         // Add a place holder info to propagate the query
78         AppInfo placeHolder = new AppInfo();
79         placeHolder.title = query;
80         item.itemInfo = placeHolder;
81         return item;
82     }
83 
84     /**
85      * Filters {@link AppInfo}s matching specified query
86      */
87     @AnyThread
getTitleMatchResult(List<AppInfo> apps, String query)88     public static ArrayList<AdapterItem> getTitleMatchResult(List<AppInfo> apps, String query) {
89         // Do an intersection of the words in the query and each title, and filter out all the
90         // apps that don't match all of the words in the query.
91         final String queryTextLower = query.toLowerCase();
92         final ArrayList<AdapterItem> result = new ArrayList<>();
93         StringMatcherUtility.StringMatcher matcher =
94                 StringMatcherUtility.StringMatcher.getInstance();
95 
96         int resultCount = 0;
97         int total = apps.size();
98         for (int i = 0; i < total && resultCount < MAX_RESULTS_COUNT; i++) {
99             AppInfo info = apps.get(i);
100             if (StringMatcherUtility.matches(queryTextLower, info.title.toString(), matcher)) {
101                 result.add(AdapterItem.asApp(info));
102                 resultCount++;
103             }
104         }
105         return result;
106     }
107 }
108