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.messaging.ui.mediapicker; 17 18 import com.google.common.base.Preconditions; 19 20 import javax.annotation.concurrent.ThreadSafe; 21 22 /** 23 * Keeps track of the speech level as last observed by the recognition 24 * engine as microphone data flows through it. Can be polled by the UI to 25 * animate its views. 26 */ 27 @ThreadSafe 28 public class AudioLevelSource { 29 private volatile int mSpeechLevel; 30 private volatile Listener mListener; 31 32 public static final int LEVEL_UNKNOWN = -1; 33 34 public interface Listener { 35 void onSpeechLevel(int speechLevel); 36 } 37 38 public void setSpeechLevel(int speechLevel) { 39 Preconditions.checkArgument(speechLevel >= 0 && speechLevel <= 100 || 40 speechLevel == LEVEL_UNKNOWN); 41 mSpeechLevel = speechLevel; 42 maybeNotify(); 43 } 44 45 public int getSpeechLevel() { 46 return mSpeechLevel; 47 } 48 49 public void reset() { 50 setSpeechLevel(LEVEL_UNKNOWN); 51 } 52 53 public boolean isValid() { 54 return mSpeechLevel > 0; 55 } 56 57 private void maybeNotify() { 58 final Listener l = mListener; 59 if (l != null) { 60 l.onSpeechLevel(mSpeechLevel); 61 } 62 } 63 64 public synchronized void setListener(Listener listener) { 65 mListener = listener; 66 } 67 68 public synchronized void clearListener(Listener listener) { 69 if (mListener == listener) { 70 mListener = null; 71 } 72 } 73 } 74
