Приложение для камеры Android: кнопка Capture не работает?

Question

Я уже давно работаю над этим приложением для камеры. В основном, я хочу сделать снимок (и сохранить его внутри), а затем отобразить это изображение в следующем мероприятии. Предварительный просмотр работает отлично, но когда я нажимаю кнопку Capture на MainActivity, появляется сообщение об ошибке «К сожалению, myApplication остановился», и приложение выходит из строя. AndroidStudio не дает мне никакой информации журнала событий либо ...

Вот основная деятельность (что-то не так с SendInfo?):

public class MainActivity extends ActionBarActivity { 
public final static String EXTRA_MESSAGE = "File_name"; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    // Create an instance of Camera 
    Camera mCamera = getCameraInstance(); 

    // Create our Preview view and set it as the content of our activity. 
    CameraPreview mPreview = new CameraPreview(this, mCamera); 
    FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview); 
    preview.addView(mPreview); 

    // Add a listener to the Capture button 
    Button captureButton = (Button) findViewById(R.id.button_capture); 
    captureButton.setOnClickListener(new View.OnClickListener() { 

     @Override 
     public void onClick(View v) { 
      Camera mCamera = getCameraInstance(); 
      // get an image from the camera 
      mCamera.takePicture(null, null, mPicture); 
     } 
     } 
    ); 
} 
////////////////////// 
public void sendInfo(View view) 
{ 
    Intent intent = new Intent(this,show_image.class); 
     Uri fileUri = getOutputMediaFileUri(1); 
    intent.putExtra(EXTRA_MESSAGE, fileUri.toString()); 
    startActivity(intent); 
} 
///////////////// 
private Camera.PictureCallback mPicture = new Camera.PictureCallback() { 

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

     File pictureFile = getOutputMediaFile(MEDIA_TYPE_IMAGE); 
     if (pictureFile == null){ 
      Log.d("Logtag:", "Error creating media file, check storage permissions: " 
        ); 
      return; 
     } 

     try { 
      FileOutputStream fos = new FileOutputStream(pictureFile); 
      fos.write(data); 
      fos.close(); 
     } catch (FileNotFoundException e) { 
      Log.d("Logtag:", "File not found: " + e.getMessage()); 
     } catch (IOException e) { 
      Log.d("Logtag:", "Error accessing file: " + e.getMessage()); 
     } 
    } 
}; 


@Override 
public boolean onCreateOptionsMenu(Menu menu) { 
    // Inflate the menu; this adds items to the action bar if it is present. 
    getMenuInflater().inflate(R.menu.menu_main, menu); 
    return true; 
} 

@Override 
public boolean onOptionsItemSelected(MenuItem item) { 
    // Handle action bar item clicks here. The action bar will 
    // automatically handle clicks on the Home/Up button, so long 
    // as you specify a parent activity in AndroidManifest.xml. 
    int id = item.getItemId(); 

    //noinspection SimplifiableIfStatement 
    if (id == R.id.action_settings) { 
     return true; 
    } 

    return super.onOptionsItemSelected(item); 
} 
/** A safe way to get an instance of the Camera object. */ 
public Camera getCameraInstance(){ 
    Camera c = null; 
    try { 
     c = Camera.open(); // attempt to get a Camera instance 
    } 
    catch (Exception e){ 
     // Camera is not available (in use or does not exist) 
     Toast.makeText(getApplicationContext(), "Camera is not available (in use or does not exist)", 
       Toast.LENGTH_LONG).show(); 
    } 
    return c; // returns null if camera is unavailable 
} 





public static final int MEDIA_TYPE_IMAGE = 1; 
public static final int MEDIA_TYPE_VIDEO = 2; 

/** Create a file Uri for saving an image or video */ 
private static Uri getOutputMediaFileUri(int type){ 
    return Uri.fromFile(getOutputMediaFile(type)); 
} 


/** Create a File for saving an image or video */ 
private static File getOutputMediaFile(int type){ 
    // To be safe, you should check that the SDCard is mounted 
    // using Environment.getExternalStorageState() before doing this. 

    File mediaStorageDir = new  File(Environment.getExternalStoragePublicDirectory(
      Environment.DIRECTORY_PICTURES), "MyCameraApp"); 
    // This locat ion works best if you want the created images to be shared 
    // between applications and persist after your app has been uninstalled. 

    // Create the storage directory if it does not exist 
    if (! mediaStorageDir.exists()){ 
     if (! mediaStorageDir.mkdirs()){ 
      Log.d("Logtag", "failed to create directory"); 
      return null; 
     } 
    } 

    // Create a media file name 
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date()); 
    File mediaFile; 
    if (type == MEDIA_TYPE_IMAGE){ 
     mediaFile = new File(mediaStorageDir.getPath() + File.separator + 
       "IMG_"+ timeStamp + ".jpg"); 
    } else if(type == MEDIA_TYPE_VIDEO) { 
     mediaFile = new File(mediaStorageDir.getPath() + File.separator + 
       "VID_"+ timeStamp + ".mp4"); 
    } else { 
     return null; 
    } 

    return mediaFile; 
} 
} 

А вот вторая активность, которая должна быть отображения изображения. ..

public class show_image extends ActionBarActivity { 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    Intent intent = getIntent(); 
    String stringURI = intent.getStringExtra(MainActivity.EXTRA_MESSAGE); 
// Uri uri = Uri.parse(stringURI); 
    Bitmap bitmap = BitmapFactory.decodeFile(stringURI); 
    ImageView imageView = new ImageView(this); 
    imageView.setImageBitmap(bitmap); 
    setContentView(imageView); 


} 

public static Bitmap decodeFile(File f, final int maxSize) { 

    Bitmap b = null; 
    // Decode image size 
    BitmapFactory.Options o = new BitmapFactory.Options(); 
    o.inJustDecodeBounds = true; 

    FileInputStream fis = null; 
    try { 
     fis = new FileInputStream(f); 
     BitmapFactory.decodeStream(fis, null, o); 
     fis.close(); 

     int scale = 1; 
     if (o.outHeight > maxSize || o.outWidth > maxSize) { 
      scale = (int) Math.pow(2, (int) Math.round(Math.log(maxSize/(double) Math.max(o.outHeight, o.outWidth))/Math.log(0.5))); 
     } 

     // Decode with inSampleSize 
     BitmapFactory.Options o2 = new BitmapFactory.Options(); 
     o2.inSampleSize = scale; 

     fis = new FileInputStream(f); 
     b = BitmapFactory.decodeStream(fis, null, o2); 

    } catch (Exception e) { 
     Log.e("Logtag", "Error processing bitmap", e); 
    } finally { 
     //FileUtil.closeQuietly(fis); 
    } 

    return b; 
} 




@Override 
public boolean onOptionsItemSelected(MenuItem item) { 
    // Handle action bar item clicks here. The action bar will 
    // automatically handle clicks on the Home/Up button, so long 
    // as you specify a parent activity in AndroidManifest.xml. 
    int id = item.getItemId(); 

    //noinspection SimplifiableIfStatement 
    if (id == R.id.action_settings) { 
     return true; 
    } 

    return super.onOptionsItemSelected(item); 
    } 
} 

Выход из журнала Cat:

02-25 00:53:11.907 13191-13191/edu.ramapo.camer I/System.out﹕ debugger has settled (1480) 

02-25 00:53:12.177 13191-13191/edu.ramapo.camer I/dalvikvm﹕ Could not find method android.view.ViewGroup.onNestedScrollAccepted, referenced from method android.support.v7.internal.widget.ActionBarOverlayLayout.onNestedScrollAccepted 

02-25 00:53:12.177 13191-13191/edu.ramapo.camer W/dalvikvm﹕ VFY: unable to resolve virtual method 11357: Landroid/view/ViewGroup;.onNestedScrollAccepted (Landroid/view/View;Landroid/view/View;I)V 

02-25 00:53:12.177 13191-13191/edu.ramapo.camer D/dalvikvm﹕ VFY: replacing opcode 0x6f at 0x0000 

02-25 00:53:12.177 13191-13191/edu.ramapo.camer I/dalvikvm﹕ Could not find method android.view.ViewGroup.onStopNestedScroll, referenced from method android.support.v7.internal.widget.ActionBarOverlayLayout.onStopNestedScroll 

02-25 00:53:12.177 13191-13191/edu.ramapo.camer W/dalvikvm﹕ VFY: unable to resolve virtual method 11363: Landroid/view/ViewGroup;.onStopNestedScroll (Landroid/view/View;)V 

02-25 00:53:12.177 13191-13191/edu.ramapo.camer D/dalvikvm﹕ VFY: replacing opcode 0x6f at 0x0000 

02-25 00:53:12.177 13191-13191/edu.ramapo.camer I/dalvikvm﹕ Could not find method android.support.v7.internal.widget.ActionBarOverlayLayout.stopNestedScroll, referenced from method android.support.v7.internal.widget.ActionBarOverlayLayout.setHideOnContentScrollEnabled 

02-25 00:53:12.177 13191-13191/edu.ramapo.camer W/dalvikvm﹕ VFY: unable to resolve virtual method 9047: Landroid/support/v7/internal/widget/ActionBarOverlayLayout;.stopNestedScroll()V 

02-25 00:53:12.177 13191-13191/edu.ramapo.camer D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x000e 

02-25 00:53:12.207 13191-13191/edu.ramapo.camer I/dalvikvm﹕ Could not find method android.content.res.TypedArray.getChangingConfigurations, referenced from method android.support.v7.internal.widget.TintTypedArray.getChangingConfigurations 

02-25 00:53:12.207 13191-13191/edu.ramapo.camer W/dalvikvm﹕ VFY: unable to resolve virtual method 365: Landroid/content/res/TypedArray;.getChangingConfigurations()I 

02-25 00:53:12.207 13191-13191/edu.ramapo.camer D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0002 

02-25 00:53:12.207 13191-13191/edu.ramapo.camer I/dalvikvm﹕ Could not find method android.content.res.TypedArray.getType, referenced from method android.support.v7.internal.widget.TintTypedArray.getType 

02-25 00:53:12.207 13191-13191/edu.ramapo.camer W/dalvikvm﹕ VFY: unable to resolve virtual method 387: Landroid/content/res/TypedArray;.getType (I)I 

02-25 00:53:12.207 13191-13191/edu.ramapo.camer D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0002 

02-25 00:53:13.068 13191-13191/edu.ramapo.camer D/libEGL﹕ loaded /system/lib/egl/libEGL_adreno200.so 

02-25 00:53:13.068 13191-13191/edu.ramapo.camer D/libEGL﹕ loaded /system/lib/egl/libGLESv1_CM_adreno200.so 

02-25 00:53:13.078 13191-13191/edu.ramapo.camer D/libEGL﹕ loaded /system/lib/egl/libGLESv2_adreno200.so 

02-25 00:53:13.078 13191-13191/edu.ramapo.camer I/Adreno200-EGL﹕ <qeglDrvAPI_eglInitialize:265>: EGL 1.4 QUALCOMM build: HAREESHG_Nondeterministic_AU+PATCH[ES]_msm8960_JB_1.9.6_MR2_CL3219408_release_ENGG (CL3219408) 
    Build Date: 09/28/13 Sat 
    Local Branch: hhh 
    Remote Branch: quic/jb_1.9.6_1 
    Local Patches: 8d50ec23e42ef52b570aa6ff1650afac0b503d78 CL3219408: Fix in the Glreadpixels for negative offsets and larger dimensions. 
    801859126f6ca69482b39a34ca61447e3f7cded8 rb: fix panel settings to clear undrawn/undefined buffers 
    Reconstruct Branch: LOCAL_PATCH[ES] 

02-25 00:53:13.118 13191-13191/edu.ramapo.camer D/OpenGLRenderer﹕ Enabling debug mode 0 

02-25 00:53:27.353 13191-13191/edu.ramapo.camer D/Logtag﹕ failed to create directory 

02-25 00:53:27.353 13191-13191/edu.ramapo.camer D/Logtag:﹕ Error creating media file, check storage permissions: 

Answer 1

Я думаю, что причина для авария - это потому, что вы пытаетесь получить экземпляр камеры дважды: когда ваша деятельность создана и когда нажата кнопка captureButton. Когда вы пытаетесь получить его во второй раз, он возвращает null, потому что он уже используется вашей деятельностью.

Вы должны получить экземпляр камеры один раз перед нажатием кнопки captureButton и обработкой сделанного снимка после этого.

public class MainActivity extends ActionBarActivity { 
    public final static String EXTRA_MESSAGE = "File_name"; 
    private Camera mCamera; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 

     // Create an instance of Camera 
     mCamera = getCameraInstance(); 

     // Create our Preview view and set it as the content of our activity. 
     CameraPreview mPreview = new CameraPreview(this, mCamera); 
     FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview); 
     preview.addView(mPreview); 

     // Add a listener to the Capture button 
     Button captureButton = (Button) findViewById(R.id.button_capture); 
     captureButton.setOnClickListener(new View.OnClickListener() { 

     @Override 
      public void onClick(View v) { 
      // get an image from the camera 
      mCamera.takePicture(null, null, mPicture); 
      } 
     } 
    ); 
    } 

    ... 

Редактировать

Для перехода к следующему действию, когда будет сделан снимок, вы могли бы назвать startActivity после Camera.PictureCallback спас byte массив в файл.

private Camera.PictureCallback mPicture = new Camera.PictureCallback() { 

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

     File pictureFile = getOutputMediaFile(MEDIA_TYPE_IMAGE); 
     if (pictureFile == null){ 
      Log.d("Logtag:", "Error creating media file, check storage permissions: " 
        ); 
      return; 
     } 

     try { 
      FileOutputStream fos = new FileOutputStream(pictureFile); 
      fos.write(data); 
      fos.close(); 

      Intent intent = new Intent(this,show_image.class); 
      Uri fileUri = Uri.fromFile(pictureFile); 
      intent.putExtra(EXTRA_MESSAGE, fileUri.toString()); 
      startActivity(intent); 

     } catch (FileNotFoundException e) { 
      Log.d("Logtag:", "File not found: " + e.getMessage()); 
     } catch (IOException e) { 
      Log.d("Logtag:", "Error accessing file: " + e.getMessage()); 
     } 
    } 
}; 

... 

Edit 2

Вам нужно добавить это разрешение манифеста, чтобы сохранить фото на устройстве:

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

Я надеюсь, что это помогает.