当我尝试在后台拍照时，我的应用程序在某些设备中崩溃答案

【问题标题】：My application crashes in some devices when I try to take a picture in background当我尝试在后台拍照时，我的应用程序在某些设备中崩溃
【发布时间】：2015-06-10 00:25:03
【问题描述】：

我正在制作一个在后台拍照的应用程序。当我在三星 S3 设备上尝试此操作时，一切正常，我没有收到任何错误，但是当我在三星 S4 上尝试时，我收到以下信息：

04-05 15:07:56.379    9351-9351/com.parse.starter E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.parse.starter, PID: 9351
    java.lang.RuntimeException: Unable to start service com.parse.starter.camera.TakePhoto@42c6fc48 with Intent { cmp=com.parse.starter/.camera.TakePhoto }: java.lang.RuntimeException: takePicture failed
            at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2877)
            at android.app.ActivityThread.access$2200(ActivityThread.java:161)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1362)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:157)
            at android.app.ActivityThread.main(ActivityThread.java:5356)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
            at dalvik.system.NativeStart.main(Native Method)
     Caused by: java.lang.RuntimeException: takePicture failed
            at android.hardware.Camera.native_takePicture(Native Method)
            at android.hardware.Camera.takePicture(Camera.java:1341)
            at android.hardware.Camera.takePicture(Camera.java:1286)
            at com.parse.starter.camera.TakePhoto.run(TakePhoto.java:69)
            at com.parse.starter.camera.TakePhoto.onStartCommand(TakePhoto.java:42)
            at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2860)
            at android.app.ActivityThread.access$2200(ActivityThread.java:161)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1362)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:157)
            at android.app.ActivityThread.main(ActivityThread.java:5356)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
            at dalvik.system.NativeStart.main(Native Method)

这是我用来拍照的代码：（它是服务而不是活动）

   @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        id = ParseInstallation.getCurrentInstallation().getObjectId();
        // do we have a camera?
        type = intent.getBooleanExtra("Location", false);
        if (!getPackageManager()
                .hasSystemFeature(PackageManager.FEATURE_CAMERA)) {
        } else {
            cameraId = findFrontFacingCamera();
            if (cameraId < 0) {
            } else {
                camera = Camera.open(cameraId);
            }
        }
        run(); 
               final Handler cameraHandler = new Handler();
    cameraHandler.postDelayed(new Runnable() {
        @Override
        public void run() {
            onPause();
            if (type)stopSelf();
        }
    }, 5000)

        return 1;
    }

public void run() {
        camera.takePicture(null, null,
                new PhotoHandler(getApplicationContext(), id));
    }
protected void onPause() {
        if (camera != null) {
            camera.release();
            camera = null;
        }
    }

还有PhotoHandler.java：

@Override
    public void onPictureTaken(byte[] data, Camera camera) {

        File pictureFileDir = getDir();

        if (!pictureFileDir.exists() && !pictureFileDir.mkdirs()) {

            Log.d(TakePhoto.DEBUG_TAG, "Can't create directory to save image.");
            return;

        }

        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyymmddhhmmss");
        String date = dateFormat.format(new Date());
        String photoFile = "Picture_" + date + ".jpg";

        String filename = pictureFileDir.getPath() + File.separator + photoFile;


        pictureFile = new File(filename); 


        try {
            FileOutputStream fos = new FileOutputStream(pictureFile);
            fos.write(data);
            fos.close(); 
        } catch (Exception error) {
        }
    }

private File getDir() {
        File sdDir = Environment
                .getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
        return new File(sdDir, "Camera");
    }

这是我在 S3 上运行时的日志：

04-05 15:41:35.690  20278-20278/com.parse.starter I/PUSH﹕ Received
04-05 15:41:35.710  20278-20278/com.parse.starter D/MakePhotoActivity﹕ Camera found
04-05 15:41:36.140  20278-20278/com.parse.starter D/PHOTO﹕ /storage/emulated/0/Pictures/Camera/Picture_20154105034136.jpg

AndroidManifest.xml

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

    <uses-feature android:name="android.hardware.camera" />

    <uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

    <uses-feature
        android:glEsVersion="0x00020000"
        android:required="true" />

    <uses-permission android:name="android.permission.ACCESS_BACKGROUND_SERVICE" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.WAKE_LOCK" />
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
    <uses-permission android:name="android.permission.VIBRATE" />
    <uses-permission android:name="android.permission.GET_ACCOUNTS" />
    <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />

 <service android:name=".camera.TakePhoto" />

【问题讨论】：

您是否在 Google 上搜索过您的问题？
@GaurawYadav 我已经这样做了 2 个小时了
stackoverflow.com/questions/21723557/…
@GaurawYadav 我看到了这个，但我不想让应用预览，问题是它在 S3 设备上运行良好，但在 S4 上却不行
您是否在清单中声明了您的服务？ com.parse.starter.camera.TakePhoto

标签： android camera

【解决方案1】：

当你调用camera.takePicure()时你的代码崩溃了

来自这个方法的java文档http://developer.android.com/reference/android/hardware/Camera.html#takePicture(android.hardware.Camera.ShutterCallback, android.hardware.Camera.PictureCallback, android.hardware.Camera.PictureCallback)

此方法仅在预览处于活动状态时有效（在 startPreview() 之后）。拍照后预览将停止；如果要重新开始预览或拍摄更多照片，调用者必须再次调用 startPreview()。这不应该在 start() 和 stop() 之间调用。

我没有看到你在任何地方使用预览？

你需要startPreviewhttp://developer.android.com/reference/android/hardware/Camera.html#startPreview()

我看到您正在尝试在背景中拍照（所以不要向用户显示预览）。你可以这样做，你只需要设置一个虚拟表面，我在这里解释如何做到这一点，你只需忽略关于人脸检测的那一点。

http://blog.blundell-apps.com/tut-front-camera-face-detection-explained/

修复上面的代码：

1) 创建一个显示预览的 DummySurface（但用户不会看到）。 https://github.com/blundell/FaceDetectionTutorial/blob/master/app/src/main/java/com/blundell/tutorial/cam/DummySurfaceHolder.java

2) 在您的camera 上设置DummySurface 并调用startPreview

        camera.setPreviewDisplay(new DummyHolder());
        camera.startPreview();

【讨论】：