RecognitionListener.java revision 79896bd123aa3bc69c6455d4e2ddf2b2b555e6e5 
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 */
16package android.speech;
17
18import android.content.Intent;
19import android.os.Bundle;
20
21/**
22 * Used for receiving notifications from the RecognitionManager when the
23 * recognition related events occur. All the callbacks are executed on the
24 * Application main thread.
25 */
26public interface RecognitionListener {
27
28    /**
29     * Called when RecognitionManager is successfully initialized
30     */
31    void onInit();
32
33    /**
34     * Called when the endpointer is ready for the user to start speaking.
35     *
36     * @param params parameters set by the recognition service. Reserved for future use.
37     */
38    void onReadyForSpeech(Bundle params);
39
40    /**
41     * The user has started to speak.
42     */
43    void onBeginningOfSpeech();
44
45    /**
46     * The sound level in the audio stream has changed. There is no guarantee that this method will
47     * be called.
48     *
49     * @param rmsdB the new RMS dB value
50     */
51    void onRmsChanged(float rmsdB);
52
53    /**
54     * More sound has been received. The purpose of this function is to allow giving feedback to the
55     * user regarding the captured audio. There is no guarantee that this method will be called.
56     *
57     * @param buffer a buffer containing a sequence of big-endian 16-bit integers representing a
58     *        single channel audio stream. The sample rate is implementation dependent.
59     */
60    void onBufferReceived(byte[] buffer);
61
62    /**
63     * Called after the user stops speaking.
64     */
65    void onEndOfSpeech();
66
67    /**
68     * A network or recognition error occurred.
69     *
70     * @param error code is defined in {@link RecognitionManager}
71     */
72    void onError(int error);
73
74    /**
75     * Called when recognition results are ready.
76     *
77     * @param results the recognition results. To retrieve the results in {@code
78     *        ArrayList<String>} format use {@link Bundle#getStringArrayList(String)} with
79     *        {@link RecognitionManager#RECOGNITION_RESULTS_STRING_ARRAY} as a parameter
80     */
81    void onResults(Bundle results);
82
83    /**
84     * Called when partial recognition results are available. The callback might be called at any
85     * time between {@link #onBeginningOfSpeech()} and {@link #onResults(Bundle)} when partial
86     * results are ready. This method may be called zero, one or multiple times for each call to
87     * {@link RecognitionManager#startListening(Intent)}, depending on the speech recognition
88     * service implementation.
89     *
90     * @param partialResults the returned results. To retrieve the results in
91     *        ArrayList<String> format use {@link Bundle#getStringArrayList(String)} with
92     *        {@link RecognitionManager#RECOGNITION_RESULTS_STRING_ARRAY} as a parameter
93     */
94    void onPartialResults(Bundle partialResults);
95
96}
97