Question

我有以下代码用于将音频峰值和加速度计读数记录到文件中。除了没有创建或写入文件外，一切似乎都工作正常。我似乎无法弄明白。

非常感谢任何帮助。

public class Main extends Activity implements SensorEventListener {

    private SensorManager mSensorManager;
    private Sensor mAccelerometer;
    private MediaRecorder recorder = new MediaRecorder();

    private File accel;
    private File audio;
    private File audiodump;

    private FileWriter accelwriter;
    private FileWriter audiowriter;




    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        String root = Environment.getExternalStorageDirectory().getAbsolutePath();
        accel = new File(root,"accel.txt");
        audio = new File(root,"audio.txt");
        audiodump = new File(root,"audiodump.aac");

        recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
        recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
        recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
        recorder.setOutputFile(audiodump.getPath());

        setContentView(R.layout.activity_main);

        mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
        mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
    }

    public void onStartClick(View view) {
        mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);
    }

    public void onStopClick(View view) {
        mSensorManager.unregisterListener(this);
    }
    protected void onResume() {
        super.onResume();
        try {
            accelwriter = new FileWriter(accel, true);
            audiowriter = new FileWriter(audio, true);
            recorder.prepare();
            recorder.start();
        } catch(IOException e) {
            e.printStackTrace();
        }
    }

    protected void onPause() {
        super.onPause();
        try {
            recorder.stop();
            recorder.release();

            if (accelwriter != null) {
                accelwriter.close();
            }
            if (audiowriter!= null) {
                audiowriter.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    @Override
    public void onAccuracyChanged(Sensor sensor, int accuracy) {

    }

    @Override
    public void onSensorChanged(SensorEvent event) {

        String time = String.valueOf(System.currentTimeMillis());
        String amplitude = String.valueOf(recorder.getMaxAmplitude());

        float x = event.values[0];
        float y = event.values[1];
        float z = event.values[2];

        try {
            audiowriter.write(time+amplitude+"\n");
            accelwriter.write(time+x+","+y+","+z+"\n");
        } catch (IOException e) {
        e.printStackTrace();
        }

    }
}

这是清单：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="ross.pieter.pieterfinal">
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.RECORD_AUDIO" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".Main">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

这是logcat：

05-24 09:22:19.924 3229-3229/ross.pieter.pieterfinal W/System: ClassLoader referenced unknown path: /data/app/ross.pieter.pieterfinal-1/lib/x86
05-24 09:22:20.105 3229-3264/ross.pieter.pieterfinal D/OpenGLRenderer: Use EGL_SWAP_BEHAVIOR_PRESERVED: true
05-24 09:22:20.151 3229-3264/ross.pieter.pieterfinal I/OpenGLRenderer: Initialized EGL, version 1.4
05-24 09:22:55.116 3229-3229/ross.pieter.pieterfinal W/MediaRecorder: mediarecorder went away with unhandled events
05-24 09:22:55.329 3229-3264/ross.pieter.pieterfinal E/Surface: getSlotFromBufferLocked: unknown buffer: 0xb4053500
05-24 09:23:30.989 3229-3235/ross.pieter.pieterfinal W/art: Suspending all threads took: 5.202ms
05-24 09:29:04.529 32274-32274/ross.pieter.pieterfinal I/art: Late-enabling -Xcheck:jni
05-24 09:29:04.529 32274-32274/ross.pieter.pieterfinal I/art: VMHOOK: rlim_cur : 0 pid:32274
05-24 09:29:04.603 32274-32274/ross.pieter.pieterfinal W/System: ClassLoader referenced unknown path: /data/app/ross.pieter.pieterfinal-2/lib/arm
05-24 09:29:05.120 32274-32274/ross.pieter.pieterfinal W/System: ClassLoader referenced unknown path: /data/app/ross.pieter.pieterfinal-2/lib/arm
05-24 09:29:05.220 32274-32274/ross.pieter.pieterfinal D/MediaRecorder: Current Package Name: ross.pieter.pieterfinal
05-24 09:29:05.259 32274-32274/ross.pieter.pieterfinal E/SensorManager: uid = 10042
05-24 09:29:05.261 32274-32274/ross.pieter.pieterfinal D/MediaRecorder: getMaxAllowedFileSizeByPath
05-24 09:29:05.263 32274-32274/ross.pieter.pieterfinal D/MediaRecorder: no match storage volume found!
05-24 09:29:05.382 32274-32324/ross.pieter.pieterfinal I/Adreno-EGL: <qeglDrvAPI_eglInitialize:379>: EGL 1.4 QUALCOMM build: Nondeterministic_AU_msm8974_LA.BF.1.1.3__release_AU (I3fa967cfef)
                                                                     OpenGL ES Shader Compiler Version: E031.28.00.02
                                                                     Build Date: 09/29/15 Tue
                                                                     Local Branch: mybranch14683032
                                                                     Remote Branch: quic/master
                                                                     Local Patches: NONE
                                                                     Reconstruct Branch: NOTHING
05-24 09:29:06.633 32274-32274/ross.pieter.pieterfinal I/SensorManager: registerListenerImpl: listener = ross.pieter.pieterfinal.Main@2e56edc, sensor = {Sensor name="Accelerometer Sensor", vendor="HTC Group Ltd.", version=1, type=1, maxRange=19.6133, resolution=0.01, power=0.17, minDelay=10000}, delay = 200000, handler = null
05-24 09:29:09.490 32274-32274/ross.pieter.pieterfinal I/SensorManager: unregisterListenerImpl++: listener = ross.pieter.pieterfinal.Main@2e56edc
05-24 09:29:10.367 32274-32274/ross.pieter.pieterfinal I/SensorManager: registerListenerImpl: listener = ross.pieter.pieterfinal.Main@2e56edc, sensor = {Sensor name="Accelerometer Sensor", vendor="HTC Group Ltd.", version=1, type=1, maxRange=19.6133, resolution=0.01, power=0.17, minDelay=10000}, delay = 200000, handler = null
05-24 09:29:12.437 32274-32274/ross.pieter.pieterfinal I/SensorManager: unregisterListenerImpl++: listener = ross.pieter.pieterfinal.Main@2e56edc
05-24 09:29:12.809 32274-32274/ross.pieter.pieterfinal I/SensorManager: registerListenerImpl: listener = ross.pieter.pieterfinal.Main@2e56edc, sensor = {Sensor name="Accelerometer Sensor", vendor="HTC Group Ltd.", version=1, type=1, maxRange=19.6133, resolution=0.01, power=0.17, minDelay=10000}, delay = 200000, handler = null
05-24 09:29:13.215 32274-32274/ross.pieter.pieterfinal I/SensorManager: unregisterListenerImpl++: listener = ross.pieter.pieterfinal.Main@2e56edc
05-24 09:29:13.614 32274-32274/ross.pieter.pieterfinal I/SensorManager: registerListenerImpl: listener = ross.pieter.pieterfinal.Main@2e56edc, sensor = {Sensor name="Accelerometer Sensor", vendor="HTC Group Ltd.", version=1, type=1, maxRange=19.6133, resolution=0.01, power=0.17, minDelay=10000}, delay = 200000, handler = null
05-24 09:29:13.986 32274-32274/ross.pieter.pieterfinal I/SensorManager: unregisterListenerImpl++: listener = ross.pieter.pieterfinal.Main@2e56edc
05-24 09:29:14.340 32274-32274/ross.pieter.pieterfinal I/SensorManager: registerListenerImpl: listener = ross.pieter.pieterfinal.Main@2e56edc, sensor = {Sensor name="Accelerometer Sensor", vendor="HTC Group Ltd.", version=1, type=1, maxRange=19.6133, resolution=0.01, power=0.17, minDelay=10000}, delay = 200000, handler = null

Answer 1

原来代码很好。
在重新启动之前，文件可以通过某些设备上的MTP连接保持不可见在这里找到答案： https://android.stackexchange.com/questions/46315/not-all-files-are-visible-over-mtp

文件没有写在android中

1 个答案: