Rexsee API介绍：Android音频录制，AudioRecorder函数与源码
Audio系统在Android中负责音频方面输入/输出层次，一般负责播放PCM声音输出和从外部获取PCM声音，以及管理声音设备和设置。这里主要是谈谈其中录制这块：AudioRecorder。
相对于MediaRecorder来说，AudioRecorder更接近底层，为我们封装的方法也更少。而且音频的采样率、声道等等都可以参数配置，但是问题是在模拟器中AudioRecorder却不怎么好用。
关于Audio系统中其它几个类，如AudioCapture、AudioPlayer，也可以在rexsee的开源社区里找到：http://www.rexsee.com/CN/helpReference.php
【函数】 void record()
【说明】 录制音频。录制成功触发事件onRecordAudioSuccessed，失败则触发onRecordAudioFailed。
【返回】 无
【示例】
rexseeAudioRecorder.record();
【函数】 void upload(String action,String name)
【说明】 将录制好的音频直接上传，通常在onRecordAudioSuccessed事件中调用。
【返回】 无
【参数】 action：上传的服务器程序url，等同于HTML中<form action="......">中的action。
name：上传名称，等同于HTML中<input type="file" name="......">中的name。
action指向的服务器程序和HTML中表单对应的程序相同，示例的服务器程序参见rexseeUpload对象。
rexseeAudioRecorder.java源码。。
/*
* Copyright (C) 2011 The Rexsee Open Source Project
*
* Licensed under the Rexsee License, Version 1.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.rexsee.com/CN/legal/license.html
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package rexsee.multimedia;
import rexsee.core.browser.ActivityResult.ActivityResultListener;
import rexsee.core.browser.JavascriptInterface;
import rexsee.core.browser.RexseeBrowser;
import rexsee.core.browser.UrlListener;
import rexsee.core.lang.RexseeLanguage;
import rexsee.core.transportation.RexseeUpload;
import android.app.Activity;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.provider.MediaStore.Audio.Media;
public class RexseeAudioRecorder implements JavascriptInterface {
private static final String INTERFACE_NAME = "AudioRecorder";
@Override
public String getInterfaceName() {
return mBrowser.application.resources.prefix + INTERFACE_NAME;
}
@Override
public JavascriptInterface getInheritInterface(RexseeBrowser childBrowser) {
return this;
}
@Override
public JavascriptInterface getNewInterface(RexseeBrowser childBrowser) {
return new RexseeAudioRecorder(childBrowser);
}
public static final String EVENT_ONRECORDAUDIOSUCCESSED = "onRecordAudioSuccessed";
public static final String EVENT_ONRECORDAUDIOFAILED = "onRecordAudioFailed";
public static final String URI_MEDIA_AUDIO = "content://media/external/audio/media";
private String mediaFile = null;
private final RexseeBrowser mBrowser;
public RexseeAudioRecorder(RexseeBrowser browser) {
mBrowser = browser;
browser.eventList.add(EVENT_ONRECORDAUDIOSUCCESSED);
browser.eventList.add(EVENT_ONRECORDAUDIOFAILED);
browser.urlListeners.add(new UrlListener(mBrowser.application.resources.prefix + ":audio") {
@Override
public void run(Context context, final RexseeBrowser browser, final String url) {
new Thread() {
@Override
public void run() {
String html = "<HTML><HEAD><TITLE>" + url + "</TITLE></HEAD>";
html += "<BODY style='margin:0px;background-color:black;color:white;'>";
ContentResolver contentResolver = mBrowser.getContext().getContentResolver();
browser.progressDialog.show(RexseeLanguage.PROGRESS_ONGOING);
Cursor cursor = contentResolver.query(Uri.parse(URI_MEDIA_AUDIO), new String[]{"_id", "_data"}, null, null, "_id desc");
html += "<table width=100% cellspacing=0 style='color:white;font-size:16px;'>";
if (cursor.getCount() == 0) {
html += "<tr><td style='padding:10px;'> audio found.</td></tr>";
} else {
for (int i = 0; i < cursor.getCount(); i++) {
cursor.moveToPosition(i);
html += "<tr><td onclick=\"" + browser.function.getInterfaceName() + ".go('" + URI_MEDIA_AUDIO + "/" + cursor.getInt(0) + "');\" style='border-bottom:1px solid #222222; padding:10 5 10 5;word-break:break-all;'>" + cursor.getString(1) + "</td></tr>";
}
}
cursor.close();
html += "</table>";
html += "</BODY>";
html += "</HTML>";
browser.function.loadHTMLWithoutHistory(html);
}
}.start();
}
@Override
public boolean shouldAddToHistory(Context context, RexseeBrowser browser, String url) {
return true;
}
});
}
public String getLastMediaAudio() {
ContentResolver contentResolver = mBrowser.getContext().getContentResolver();
Cursor cursor = contentResolver.query(Uri.parse(URI_MEDIA_AUDIO), new String[]{"_data"}, null, null, "_id desc");
if (cursor == null || cursor.getCount() == 0) return "";
cursor.moveToFirst();
String rtn = "file://" + cursor.getString(0);
cursor.close();
return rtn;
}
public void record() {
try {
Intent intent = new Intent(Media.RECORD_SOUND_ACTION);
mBrowser.activityResult.start(intent, new ActivityResultListener() {
@Override
public void run(int resultCode, Intent resultIntent) {
if (resultCode == Activity.RESULT_OK) {
mediaFile = getLastMediaAudio();
mBrowser.eventList.run(EVENT_ONRECORDAUDIOSUCCESSED, new String[]{mediaFile});
} else {
mediaFile = null;
mBrowser.eventList.run(EVENT_ONRECORDAUDIOFAILED);
}
}
});
} catch (Exception e) {
mBrowser.exception(getInterfaceName(), e);
}
}
public void prepareUpload() {
if (mediaFile == null) {
mBrowser.exception(getInterfaceName(), "Audio is not ready.");
} else {
RexseeUpload uploadObject = (RexseeUpload) mBrowser.interfaceList.get(mBrowser.application.resources.prefix + RexseeUpload.INTERFACE_NAME);
if (uploadObject == null) {
mBrowser.exception(getInterfaceName(), "Upload object is not ready.");
} else {
uploadObject.selectedFiles.add(mediaFile);
}
}
}
public void upload(String action, String name) {
if (mediaFile == null) {
mBrowser.exception(getInterfaceName(), "Audio is not ready.");
} else {
RexseeUpload uploadObject = (RexseeUpload) mBrowser.interfaceList.get(mBrowser.application.resources.prefix + RexseeUpload.INTERFACE_NAME);
if (uploadObject == null) {
mBrowser.exception(getInterfaceName(), "Upload object is not ready.");
} else {
uploadObject.clear();
uploadObject.selectedFiles.add(mediaFile);
uploadObject.upload(action, name);
}
}
}
}
仅对Rexsee的源码和函数事件做了整理，相关的demo或源码解析可以在Rexsee社区了解，目前Rexsee已提供了近2000个扩展，覆盖Android原生功能超过90%，且全部开放： http://www.rexsee.com/
