我是Android和Java的新手。
我在Windows 10上使用最新的Android Studio。
我只是创建了一个空活动并粘贴了
中的代码https://developer.android.com/guide/topics/media/audio-capture.html
到我的MainActivity。
根据其评论，我还在清单中添加了uses-permission。
我已经阅读了所有Q＆amp; As，我相信清单是好的。
但是我一直在使用callstack在发布结束时使setAudioSource失败。
我的Nexus 5和Nexus 5虚拟设备的错误相同。
你能帮助我吗？谢谢！<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.kyang.myapplication">
<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=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
我的代码如下：
package com.example.kyang.myapplication;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.app.Activity;
import android.widget.LinearLayout;
import android.os.Bundle;
import android.os.Environment;
import android.view.ViewGroup;
import android.widget.Button;
import android.view.View;
import android.view.View.OnClickListener;
import android.content.Context;
import android.util.Log;
import android.media.MediaRecorder;
import android.media.MediaPlayer;
import java.io.IOException;
public class MainActivity extends Activity {
private static final String LOG_TAG = "AudioRecordTest";
private static String mFileName = null;
private RecordButton mRecordButton = null;
private MediaRecorder mRecorder = null;
private PlayButton mPlayButton = null;
private MediaPlayer mPlayer = null;
private void onRecord(boolean start) {
if (start) {
startRecording();
} else {
stopRecording();
}
}
private void onPlay(boolean start) {
if (start) {
startPlaying();
} else {
stopPlaying();
}
}
private void startPlaying() {
mPlayer = new MediaPlayer();
try {
mPlayer.setDataSource(mFileName);
mPlayer.prepare();
mPlayer.start();
} catch (IOException e) {
Log.e(LOG_TAG, "prepare() failed");
}
}
private void stopPlaying() {
mPlayer.release();
mPlayer = null;
}
private void startRecording() {
mRecorder = new MediaRecorder();
mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mRecorder.setOutputFile(mFileName);
mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
try {
mRecorder.prepare();
} catch (IOException e) {
Log.e(LOG_TAG, "prepare() failed");
}
mRecorder.start();
}
private void stopRecording() {
mRecorder.stop();
mRecorder.release();
mRecorder = null;
}
class RecordButton extends Button {
boolean mStartRecording = true;
OnClickListener clicker = new OnClickListener() {
public void onClick(View v) {
onRecord(mStartRecording);
if (mStartRecording) {
setText("Stop recording");
} else {
setText("Start recording");
}
mStartRecording = !mStartRecording;
}
};
public RecordButton(Context ctx) {
super(ctx);
setText("Start recording");
setOnClickListener(clicker);
}
}
class PlayButton extends Button {
boolean mStartPlaying = true;
OnClickListener clicker = new OnClickListener() {
public void onClick(View v) {
onPlay(mStartPlaying);
if (mStartPlaying) {
setText("Stop playing");
} else {
setText("Start playing");
}
mStartPlaying = !mStartPlaying;
}
};
public PlayButton(Context ctx) {
super(ctx);
setText("Start playing");
setOnClickListener(clicker);
}
}
public MainActivity() {
mFileName = Environment.getExternalStorageDirectory().getAbsolutePath();
mFileName += "/audiorecordtest.3gp";
}
@Override
public void onPause() {
super.onPause();
if (mRecorder != null) {
mRecorder.release();
mRecorder = null;
}
if (mPlayer != null) {
mPlayer.release();
mPlayer = null;
}
}
@Override
protected void onCreate(Bundle icicle) {
super.onCreate(icicle);
LinearLayout ll = new LinearLayout(this);
mRecordButton = new RecordButton(this);
ll.addView(mRecordButton,
new LinearLayout.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT,
0));
mPlayButton = new PlayButton(this);
ll.addView(mPlayButton,
new LinearLayout.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT,
0));
setContentView(ll);
}
}
Android Monitor Verbose模式下的输出：
05-20 09:34:18.552 15335-15335/com.example.kyang.myapplication I/Process: Sending signal. PID: 15335 SIG: 9
05-20 09:35:07.850 16251-16251/com.example.kyang.myapplication W/ActivityThread: Application com.example.kyang.myapplication is waiting for the debugger on port 8100...
05-20 09:35:07.854 16251-16251/com.example.kyang.myapplication I/System.out: Sending WAIT chunk
05-20 09:35:08.273 16251-16257/com.example.kyang.myapplication I/art: Debugger is active
05-20 09:35:08.468 16251-16251/com.example.kyang.myapplication I/System.out: Debugger has connected
05-20 09:35:08.468 16251-16251/com.example.kyang.myapplication I/System.out: waiting for debugger to settle...
05-20 09:35:08.669 16251-16251/com.example.kyang.myapplication I/System.out: waiting for debugger to settle...
05-20 09:35:08.872 16251-16251/com.example.kyang.myapplication I/System.out: waiting for debugger to settle...
05-20 09:35:09.086 16251-16251/com.example.kyang.myapplication I/System.out: waiting for debugger to settle...
05-20 09:35:09.287 16251-16251/com.example.kyang.myapplication I/System.out: waiting for debugger to settle...
05-20 09:35:09.488 16251-16251/com.example.kyang.myapplication I/System.out: waiting for debugger to settle...
05-20 09:35:09.690 16251-16251/com.example.kyang.myapplication I/System.out: waiting for debugger to settle...
05-20 09:35:09.891 16251-16251/com.example.kyang.myapplication I/System.out: waiting for debugger to settle...
05-20 09:35:10.092 16251-16251/com.example.kyang.myapplication I/System.out: waiting for debugger to settle...
05-20 09:35:10.293 16251-16251/com.example.kyang.myapplication I/System.out: debugger has settled (1377)
05-20 09:35:10.310 16251-16251/com.example.kyang.myapplication W/System: ClassLoader referenced unknown path: /data/app/com.example.kyang.myapplication-2/lib/x86_64
05-20 09:35:10.571 16251-16251/com.example.kyang.myapplication W/System: ClassLoader referenced unknown path: /data/app/com.example.kyang.myapplication-2/lib/x86_64
05-20 09:35:10.883 16251-16304/com.example.kyang.myapplication D/OpenGLRenderer: Use EGL_SWAP_BEHAVIOR_PRESERVED: true
[ 05-20 09:35:10.893 16251:16251 D/ ]
HostConnection::get() New Host Connection established 0x7fdfb5ffea40, tid 16251
[ 05-20 09:35:10.940 16251:16304 D/ ]
HostConnection::get() New Host Connection established 0x7fdfb9ac6400, tid 16304
05-20 09:35:10.976 16251-16304/com.example.kyang.myapplication I/OpenGLRenderer: Initialized EGL, version 1.4
05-20 09:35:12.406 16251-16251/com.example.kyang.myapplication D/AndroidRuntime: Shutting down VM
--------- beginning of crash
05-20 09:35:12.410 16251-16251/com.example.kyang.myapplication E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.kyang.myapplication, PID: 16251
java.lang.RuntimeException: setAudioSource failed.
at android.media.MediaRecorder.setAudioSource(Native Method)
at com.example.kyang.myapplication.MainActivity.startRecording(MainActivity.java:65)
at com.example.kyang.myapplication.MainActivity.onRecord(MainActivity.java:33)
at com.example.kyang.myapplication.MainActivity.access$000(MainActivity.java:20)
at com.example.kyang.myapplication.MainActivity$RecordButton$1.onClick(MainActivity.java:90)
at android.view.View.performClick(View.java:5198)
at android.view.View$PerformClick.run(View.java:21147)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
答案 0 :(得分：3)
是的！您可以从Activity或Fragment调用requestPermissions（）。此示例适用于来自活动的调用
int YOUR_REQUEST_CODE = 200; // could be something else..
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) //check if permission request is necessary
{
ActivityCompat.requestPermissions(this, new String[] {android.Manifest.permission.RECORD_AUDIO, android.Manifest.permission.WRITE_EXTERNAL_STORAGE}, YOUR_REQUEST_CODE});
}
然后，如果授予了权限，您可以签入onRequestPermissionResult：
@Override
public void onRequestPermissionsResult(final int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
if(requestCode == YOUR_REQUEST_CODE)
{
Log.i(TAG, "Permission granted");
//do what you wanted to do
}
} else {
Log.d(TAG, "Permission failed");
}
}
对于良好实践，您应该检查是否已经授予了权限（以避免每次询问都会让用户烦恼..）
if (PackageManager.PERMISSION_GRANTED == ActivityCompat.checkSelfPermission(getApplicationContext(),permissionString))
答案 1 :(得分：0)
最后我发现我需要去设置 - ＆gt; App-＆gt; Permission-＆gt;手动滑动麦克风和存储。为什么我没有发现任何提及此事。
有没有办法明确提示用户提供这些权限，而不是使用隐藏在手机深处的设置进行静默崩溃？