java - Android 中的相机 Intent 问题

Question

我使用相机 Intent 让用户拍摄照片并将其发送到另一个 Activity 以供进一步使用。我在相机 Intent 的 putExtra 方法中包含了 EXTRA_OUTPUT 部分，这样我就可以获得全尺寸图像而不是缩略图。问题是，在捕获图像后，我被重定向到 MainActivity。当我在文件管理器中看到时，我发现图像已保存。请帮忙。

 CameraButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
                String imageFileName = timeStamp + ".jpg";
                File storageDir = Environment.getExternalStoragePublicDirectory(
                        Environment.DIRECTORY_PICTURES);
                pictureImagePath = storageDir.getAbsolutePath() + "/" + imageFileName;
                file = new File(pictureImagePath);
                outputFileUri = Uri.fromFile(file);
                Intent camera = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                camera.putExtra(MediaStore.EXTRA_OUTPUT, outputFileUri);
                startActivityForResult(camera, REQUEST_IMAGE_CAPTURE);
            }
        });


@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK && null != data) {
try {

                    b = MediaStore.Images.Media.getBitmap(this.getContentResolver(), outputFileUri);
                    String filename123 = "myphoto.jpg";
                    FileOutputStream out = this.openFileOutput(filename123, Context.MODE_PRIVATE);
                    b.compress(Bitmap.CompressFormat.JPEG, 100, out);
                    out.close();
                    b.recycle();
                    Intent in1 = new Intent(this, ongallery.class);
                    in1.putExtra("picture", filename123);
                    startActivity(in1);
                }catch(Exception e)
                {
                    Toast.makeText(this,"You got Error!",Toast.LENGTH_SHORT).show();
                }
            }
        } catch (Exception e) {
            Toast.makeText(this,"Something went wrong",Toast.LENGTH_SHORT).show();
        }
    }


//OnaGallery.java
public class ongallery extends Activity {
    public  ImageView imgView;
    int xDim;
    int yDim;
String filename;
    public  Bitmap finale = null ;
    public  Bitmap bmp = null;
    public Bitmap photoEdit;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.ongallery);
        imgView = (ImageView) findViewById(R.id.imgView);
        xDim = imgView.getWidth();
        filename = getIntent().getStringExtra("picture");
        try {
            FileInputStream is = this.openFileInput(filename);
            bmp = BitmapFactory.decodeStream(is);
            is.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        Bitmap finalPhoto = decoder(filename,400,400);
            imgView.setImageBitmap(finalPhoto);
            }
    @Override
    public void onWindowFocusChanged(boolean hasFocus) {
        super.onWindowFocusChanged(hasFocus);
    }
  public Bitmap decoder(String filename, int reqWidth, int reqHeight) {
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
      String filepath = getFileStreamPath(filename).getPath();
        BitmapFactory.decodeFile(filepath, options);
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
        options.inJustDecodeBounds = false;
        finale = BitmapFactory.decodeFile(filepath, options);
        return finale;
    }
     int calculateInSampleSize( BitmapFactory.Options options, int reqWidth, int reqHeight) {
        int inSampleSize = 1;
        if (options.outHeight > reqHeight || options.outWidth > reqWidth) {
            final int halfHeight = options.outHeight / 2;
            final int halfWidth = options.outWidth / 2;
            while ((halfHeight / inSampleSize) > reqHeight
                    && (halfWidth / inSampleSize) > reqWidth) {
                inSampleSize *= 2;
            }
        }
        return inSampleSize;
    }
}

Answer 1

权限相机权限检查类

public class Utility {
public static final int MY_PERMISSIONS_REQUEST_READ_EXTERNAL_STORAGE = 123;
@TargetApi(Build.VERSION_CODES.JELLY_BEAN)
public static boolean checkPermission(final Context context)
{
    int currentAPIVersion = Build.VERSION.SDK_INT;
    if(currentAPIVersion>=android.os.Build.VERSION_CODES.N)
    {
        if (ContextCompat.checkSelfPermission(context, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
            if (ActivityCompat.shouldShowRequestPermissionRationale((Activity) context, Manifest.permission.READ_EXTERNAL_STORAGE)) {
                AlertDialog.Builder alertBuilder = new AlertDialog.Builder(context);
                alertBuilder.setCancelable(true);
                alertBuilder.setTitle("Permission necessary");
                alertBuilder.setMessage("External storage permission is necessary");
                alertBuilder.setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
                    @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
                    public void onClick(DialogInterface dialog, int which) {
                        ActivityCompat.requestPermissions((Activity) context, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, MY_PERMISSIONS_REQUEST_READ_EXTERNAL_STORAGE);
                    }
                });
                AlertDialog alert = alertBuilder.create();
                alert.show();
            } else {
                ActivityCompat.requestPermissions((Activity) context, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, MY_PERMISSIONS_REQUEST_READ_EXTERNAL_STORAGE);
            }
            return false;
        } else {
            return true;
        }
    } else {
        return true;
    }
}

现在在你发射相机 Intent 之前检查权限

 boolean permissionCheck = Utility.checkPermission(getActivity());
  if (permissionCheck) {
      Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
      startActivityForResult(intent, CAMERA_REQUEST);
    }

现在在 onActivityResult() 中看起来像

  @Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (resultCode == RESULT_OK) {
         if (requestCode == CAMERA_REQUEST)
            bitmap = (Bitmap) data.getExtras().get("data");
    ByteArrayOutputStream bytes = new ByteArrayOutputStream();
    bitmap.compress(Bitmap.CompressFormat.JPEG, 100, bytes);

    File destination = new File(Environment.getExternalStorageDirectory(), System.currentTimeMillis() + ".jpg");

    FileOutputStream fo;
    try {
        destination.createNewFile();
        fo = new FileOutputStream(destination);
        fo.write(bytes.toByteArray());
        fo.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    bitmap = Bitmap.createScaledBitmap(bitmap, 200, 200, false);
    // Toast.makeText(SignUpActivity.this, String.valueOf(destination), Toast.LENGTH_LONG).show();
    imageView.setImageBitmap(bitmap);
    } else if (resultCode == RESULT_CANCELED) {
        Toast.makeText(getActivity(), "Cancelled",
                Toast.LENGTH_SHORT).show();
    }

}

AndroidMenifest.xml 中的权限

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

希望对您有所帮助。