ShortcutRefresher.java revision 94e8a2be78530170f50e7895a558bf8011bbf8e8 
1/*
2 * Copyright (C) 2010 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
17package com.android.quicksearchbox;
18
19import android.content.ComponentName;
20
21import java.util.Collections;
22import java.util.HashSet;
23import java.util.Set;
24
25/**
26 * Fires off tasks to validate shortcuts, and reports the results back to a
27 * {@link Listener}.
28 */
29class ShortcutRefresher {
30
31    public interface Listener {
32        /**
33         * Called by the ShortcutRefresher when a shortcut has been refreshed.
34         *
35         * @param componentName of the source of this shortcut.
36         * @param shortcutId the id of the shortcut.
37         * @param refreshed the updated shortcut, or {@code null} if the shortcut
38         *        is no longer valid and should be deleted.
39         */
40        void onShortcutRefreshed(ComponentName componentName, String shortcutId,
41                SuggestionCursor refreshed);
42    }
43
44    private final SourceTaskExecutor mExecutor;
45    private final SourceLookup mSourceLookup;
46
47    private final Set<String> mRefreshed = Collections.synchronizedSet(new HashSet<String>());
48
49    /**
50     * Create a ShortcutRefresher that will refresh shortcuts using the given executor.
51     *
52     * @param executor Used to execute the tasks.
53     * @param sourceLookup Used to lookup suggestion sources by component name.
54     */
55    public ShortcutRefresher(SourceTaskExecutor executor, SourceLookup sourceLookup) {
56        mExecutor = executor;
57        mSourceLookup = sourceLookup;
58    }
59
60    /**
61     * Sends off the refresher tasks.
62     *
63     * @param shortcuts The shortcuts to refresh.
64     * @param listener Who to report back to.
65     */
66    public void refresh(SuggestionCursor shortcuts, final Listener listener) {
67        int count = shortcuts.getCount();
68        for (int i = 0; i < count; i++) {
69            shortcuts.moveTo(i);
70            if (shouldRefresh(shortcuts)) {
71                String shortcutId = shortcuts.getShortcutId();
72                ComponentName componentName = shortcuts.getSourceComponentName();
73                Source source = mSourceLookup.getSourceByComponentName(componentName);
74
75                // If we can't find the source then invalidate the shortcut.
76                // Otherwise, send off the refresh task.
77                if (source == null) {
78                    listener.onShortcutRefreshed(componentName, shortcutId, null);
79                } else {
80                    String extraData = shortcuts.getSuggestionIntentExtraData();
81                    ShortcutRefreshTask refreshTask = new ShortcutRefreshTask(
82                            source, shortcutId, extraData, listener);
83                    mExecutor.execute(refreshTask);
84                }
85            }
86        }
87    }
88
89    /**
90     * Returns true if the given shortcut requires refreshing.
91     */
92    public boolean shouldRefresh(SuggestionCursor shortcut) {
93        return shortcut.getShortcutId() != null
94                && ! mRefreshed.contains(makeKey(shortcut));
95    }
96
97    /**
98     * Indicate that the shortcut no longer requires refreshing.
99     */
100    public void onShortcutRefreshed(SuggestionCursor shortcut) {
101        mRefreshed.add(makeKey(shortcut));
102    }
103
104    /**
105     * Reset internal state.  This results in all shortcuts requiring refreshing.
106     */
107    public void reset() {
108        mRefreshed.clear();
109    }
110
111    /**
112     * Cancel any pending shortcut refresh requests.
113     */
114    public void cancelPendingTasks() {
115        mExecutor.cancelPendingTasks();
116    }
117
118    private static String makeKey(SuggestionCursor shortcut) {
119        return shortcut.getSourceComponentName().flattenToShortString() + "#"
120                + shortcut.getShortcutId();
121    }
122
123    /**
124     * Refreshes a shortcut with a source and reports the result to a {@link Listener}.
125     */
126    private class ShortcutRefreshTask implements SourceTask {
127        private final Source mSource;
128        private final String mShortcutId;
129        private final String mExtraData;
130        private final Listener mListener;
131
132        /**
133         * @param source The source that should validate the shortcut.
134         * @param shortcutId The shortcut to be refreshed.
135         * @param listener Who to report back to when the result is in.
136         */
137        ShortcutRefreshTask(Source source, String shortcutId, String extraData,
138                Listener listener) {
139            mSource = source;
140            mShortcutId = shortcutId;
141            mExtraData = extraData;
142            mListener = listener;
143        }
144
145        public void run() {
146            // TODO: Add latency tracking and logging.
147            SuggestionCursor refreshed = mSource.refreshShortcut(mShortcutId, mExtraData);
148            onShortcutRefreshed(refreshed);
149            mListener.onShortcutRefreshed(mSource.getComponentName(), mShortcutId, refreshed);
150        }
151
152        public Source getSource() {
153            return mSource;
154        }
155    }
156}
157