SuggestionCursor.java revision 93bd2e70b8b08da1ec37fd0e990dac05551d2e90 
1/*
2 * Copyright (C) 2009 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 */
16package com.android.quicksearchbox;
17
18import android.database.DataSetObserver;
19
20/**
21 * A sequence of suggestions, with a current position.
22 */
23public interface SuggestionCursor extends Suggestion {
24
25    /**
26     * Gets the query that the user typed to get this suggestion.
27     */
28    String getUserQuery();
29
30    /**
31     * Gets the number of suggestions in this result.
32     *
33     * @return The number of suggestions, or {@code 0} if this result represents a failed query.
34     */
35    int getCount();
36
37    /**
38     * Moves to a given suggestion.
39     *
40     * @param pos The position to move to.
41     * @throws IndexOutOfBoundsException if {@code pos < 0} or {@code pos >= getCount()}.
42     */
43    void moveTo(int pos);
44
45    /**
46     * Moves to the next suggestion, if there is one.
47     *
48     * @return {@code false} if there is no next suggestion.
49     */
50    boolean moveToNext();
51
52    /**
53     * Gets the current position within the cursor.
54     */
55    int getPosition();
56
57    /**
58     * Frees any resources used by this cursor.
59     */
60    void close();
61
62    /**
63     * Register an observer that is called when changes happen to this data set.
64     *
65     * @param observer gets notified when the data set changes.
66     */
67    void registerDataSetObserver(DataSetObserver observer);
68
69    /**
70     * Unregister an observer that has previously been registered with
71     * {@link #registerDataSetObserver(DataSetObserver)}
72     *
73     * @param observer the observer to unregister.
74     */
75    void unregisterDataSetObserver(DataSetObserver observer);
76}
77