我想用MediaRecorder录制语音，我的代码是：
public void record(View v) {
Log.d(TAG, "record");
this.mediaRecorder.setAudioChannels(1);
this.mediaRecorder.setAudioSamplingRate(44100);
this.mediaRecorder.setAudioEncodingBitRate(64000);
this.mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
this.mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
this.mediaRecorder.setOutputFile(this.file.getAbsolutePath());
this.mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AAC);
try {
this.mediaRecorder.prepare();
this.mediaRecorder.start();
// update the buttons
this.setButtonsEnabled(false, true, false);
} catch (IOException e) {
Log.e(TAG, "Failed to record()", e);
}
}
或
public void record(View v) {
Log.d(TAG, "record");
this.mediaRecorder = new MediaRecorder();
this.mediaRecorder.setAudioChannels(1);
this.mediaRecorder.setAudioSamplingRate(8000);
this.mediaRecorder.setAudioEncodingBitRate(16);
this.mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
this.mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.RAW_AMR);
this.mediaRecorder.setOutputFile(this.file.getAbsolutePath());
this.mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
try {
this.mediaRecorder.prepare();
this.mediaRecorder.start();
// update the buttons
this.setButtonsEnabled(false, true, false);
} catch (IOException e) {
Log.e(TAG, "Failed to record()", e);
}
}
在三星上一切都还可以，但戴尔的两种方法都没有成功
这是logcat：
02-01 13:56:51.094: E/AudioRecorderDemoActivity(1397): Failed to record()
02-01 13:56:51.094: E/AudioRecorderDemoActivity(1397): java.io.IOException: prepare failed.
02-01 13:56:51.094: E/AudioRecorderDemoActivity(1397): at android.media.MediaRecorder._prepare(Native Method)
02-01 13:56:51.094: E/AudioRecorderDemoActivity(1397): at android.media.MediaRecorder.prepare(MediaRecorder.java:524)
02-01 13:56:51.094: E/AudioRecorderDemoActivity(1397): at com.marakana.android.audiorecorderdemo.AudioRecorderDemoActivity.record(AudioRecorderDemoActivity.java:69)
02-01 14:05:20.074: E/AndroidRuntime(1790): FATAL EXCEPTION: main
02-01 14:05:20.074: E/AndroidRuntime(1790): java.lang.IllegalStateException: Could not execute method of the activity
答案 0 :(得分：3)
首先，你的代码看起来很好。您是否已将所需权限添加到清单文件中？
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
如果是，请尝试替换：
this.mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
通过
this.mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
不要忘记检查视频文件的路径是否正确。
答案 1 :(得分：1)
这是一个很大的问题，但有一个非常小的解决方案
在大多数情况下，我们从this.file.getAbsolutePath（）获取的文件名包含file：///作为前缀
////////////////////////////////////////////////* INCORRECT CODE */
this.mediaRecorder.setOutputFile(this.file.getAbsolutePath());
/*the above line sets a file url beginning with a "file:///"
//however, since this setOutputFile requires us to send a
//string referring to the uri, we will have to get rid of the
//"file:///" and simply write the uri */
////////////////////////////////////////////////* CORRECTED CODE BELOW */
this.mediaRecorder.setOutputFile(this.file.getAbsolutePath().substring(8));
/*the above line of code extracts the string uri eliminating
// file:/// */
希望您觉得这个答案很有帮助
答案 2 :(得分：0)
我删除了
this.mediaRecorder.setAudioEncodingBitRate(16);
方法2，现在它正在运作。
答案 3 :(得分：0)
此异常将被提出。如果以下任何一项失败：
找不到文件：确保yu指定的输出文件位置存在，否则会抛出filenotfoundexception
写入权限：您必须在清单文件中指定“写入”权限。
记录权限：在清单文件中指定记录权限。
你可以用这个..
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.RECORD_AUDIO"/>
你仍然得到错误.. 尝试显示错误。喜欢这个
try{
mRecorder.prepare();
} catch (IOException e) {
Log.e(LOG_TAG, "prepare() failed");
System.out.println(""+e); //to display the error
}
mRecorder.start（）;
答案 4 :(得分：0)
对于定位到版本> = 10+的设备，您需要使用MediaStore api，在我的情况下，找不到文件，因为该文件不在我的应用程序范围内。
答案 5 :(得分：0)
实际上，iam在我的应用程序构建期间也遇到了同样的问题，我得到了一个完美的解决方案，那就是我们应该设置所有权限，例如RECORD_AUDIO，READ_EXTERNAL_STORAGE，WRITE_EXTERNAL_STORAGE，我们应该将这些权限设置为AndroidManifest.xml和runtime在下面粘贴我的代码，其kotlin代码并运行成功
//Here when the app opening time
<!--MainActivity-->
class MainActivity: AppCompatActivity() {
companion object{
var permissionAccepted = false
var permissions = arrayOf(android.Manifest.permission.RECORD_AUDIO,
android.Manifest.permission.READ_EXTERNAL_STORAGE,
android.Manifest.permission.WRITE_EXTERNAL_STORAGE)
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
ActivityCompat.requestPermissions(this, permissions,CODE_PERMISSIONS)
setContentView(R.layout.activity_main)
}
@RequiresApi(Build.VERSION_CODES.M)
override fun onRequestPermissionsResult(
requestCode: Int,
permissions: Array<out String>,
grantResults: IntArray
) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults)
when (requestCode) {
REQUEST_CODE_PERMISSIONS -> {
permissionAccepted = grantResults[0]
== PackageManager.PERMISSION_GRANTED
&& grantResults [1] == PackageManager.PERMISSION_GRANTED
&& grantResults[2] == PackageManager.PERMISSION_GRANTED
}
}
if (!permissionAccepted){
requestPermissions(permissions, REQUEST_CODE_PERMISSIONS)
}
}
}
<!--VoiceRecordActivity-->
class VoiceRecordActivity: AppCompatActivity() {
private var mediaRecorder: MediaRecorder? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_voice_record)
//i used touch listner
audio_message_send.setOnTouchListener{ v, event ->
if (permissionAccepted)
{
//Log.e("TAG","permission accepted:$permissionAccepted")
if (event.action == MotionEvent.ACTION_DOWN) {
startRecording()
}
if (event.action == MotionEvent.ACTION_UP) {
stopRecording()
}
}else{
//Log.e("TAG","permission accepted:$permissionAccepted")
requestPermissions(permissions, REQUEST_CODE_PERMISSIONS)
}
false
}
}
private fun startRecording() {
mFile = Environment.getExternalStorageDirectory().absolutePath
+"/$formattedDate-FC00$random.aac"
if (mediaRecorder == null){
this.mediaRecorder = MediaRecorder().apply {
setOutputFile(mFile)
setAudioSource(MediaRecorder.AudioSource.MIC)
setAudioChannels(1)
setOutputFormat(MediaRecorder.OutputFormat.AAC_ADTS)
setAudioEncoder(MediaRecorder.AudioEncoder.AAC)
//Log.e("TAG", "mFIle: $mFile")
try {
this.prepare()
this.start()
} catch (e: IOException) {
e.printStackTrace()
Log.e("TAG", "error: Prepare() failed")
} catch (e: InterruptedException) {
e.printStackTrace()
} catch (e: InterruptedException) {
e.printStackTrace()
}
}
}else{
this.mediaRecorder!!.prepare()
this.mediaRecorder!!.start()
}
}
private fun stopRecording() {
mediaRecorder!!.apply {
try {
stop()
release()
}catch (e: IOException){
Log.e("TAG","error: stop${e.printStackTrace()}")
}
mediaRecorder = null
}
}
override fun onStop() {
super.onStop()
if(mediaRecorder != null) {
mediaRecorder!!.release()
mediaRecorder = null
}
}
}