LuajavaBridge 声音捕捉

首先通过luajavabridge,从Lua的代码中切换到Android下面,调用Android的声音捕捉相关代码,然后android端将是否成功捕捉到一定大小的声音结果返回给Lua。

Lua端的相关调用操作：

local aboutBtn = ui.newImageMenuItem({
        image = aboutImgPath,
        imageSelected = aboutImgSelectedPath,
        x = CommonAPI:getFixedX(180) -CommonAPI:getCenterX(),
        y = CommonAPI:getFixedY(80) -CommonAPI:getCenterY(),
        listener = function()  
             -- call Java method
            local javaClassName = "com.quick_x.sample.luajavabridge.Luajavabridge"
            local javaMethodName = "catchVoice"
            local javaParams = {
                device.cachePath,
                "I'm great !",
                function(event)
                    printf("Java method callback value is [%s]", event)
                    textInput:setText(string.format("%s", event))
                end
            }
            local javaMethodSig = "(Ljava/lang/String;Ljava/lang/String;I)V"
            luaj.callStaticMethod(javaClassName, javaMethodName, javaParams, javaMethodSig)
        end
    })

Android下面的操作：（    使用MediaRecorder来记录声音，注意这里的线程切换跟官方给的方式不一样，不过是可行的。
    开启一个独立的线程CheckMicophoneVolume，用来监听外界声音的大小，达到一定分贝，触发函数，返回给Lua结果。
    使用完MediaRecoder以后，记得stop(),然后释放它。不然第二次通过Lua来调用的时候会报错、）

----------------------------------------------------

注意我这里的cachePath是通过Lua传过来的。
cachePath的值是大概这样的：/data/data/项目包名/files/
我的就是：/data/data/com.quick_x.sample.luajavabridge/files/

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public class Luajavabridge extends Cocos2dxActivity {
    static private Luajavabridge s_instance;

    static int callbackFunction;
    static MediaRecorder mRecorder;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        s_instance = this;
    }

    static {
        System.loadLibrary("game");
    }

    public static void catchVoice(final String cachePath, final String message,
            final int luaCallbackFunction) {
        callbackFunction = luaCallbackFunction;

        s_instance.runOnUiThread(new Runnable() {
            @Override
            public void run() {
                try {
                    File soundFile = new File(cachePath+"audio.3gp");
                    
                    if(mRecorder == null){
                        mRecorder = new MediaRecorder();
                        mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
                        mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
                        mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
                        mRecorder.setOutputFile(soundFile.getAbsolutePath());
                    }
                    mRecorder.prepare();
                    mRecorder.start();
                } catch (IOException e) {
                    e.printStackTrace();
                }

                CheckMicophoneVolume thread = new CheckMicophoneVolume();
                thread.start();
            }
        });
    }

    public static void catchVoiceSuccess() {
        mRecorder.stop();
        mRecorder = null;
        s_instance.runOnGLThread(new Runnable() {
            @Override
            public void run() {
                Cocos2dxLuaJavaBridge.callLuaFunctionWithString(
                        callbackFunction, "声音捕捉成功");
                Cocos2dxLuaJavaBridge.releaseLuaFunction(callbackFunction);
            }
        });
    }

    private static class CheckMicophoneVolume extends Thread {
        private volatile boolean running = true;

        public void exit() {
            running = false;
        }

        @Override
        public void run() {    
            while (running) {
                try {
                    Thread.sleep(200);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            
                if (mRecorder == null || !running) {
                    break;
                }
        
                int x = mRecorder.getMaxAmplitude();
                Log.v("X_value", ""+x);
                if (x != 0) {
                    int f = (int) (10 * Math.log(x) / Math.log(10));
                    Log.v("value", ""+f);
                    if (f > 40) {
                        catchVoiceSuccess();
                        exit();
                    }
                }
            }
        }
    }
}

注意添加权限文件：

    <uses-permission android:name="android.permission.RECORD_AUDIO"/>
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>  
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>