java.io.FileNotFoundException: /storage/6CDB-8541/DCIM/Camera/IMG_20180523_202102.jpg (权限被拒绝)

Question

我在获取FileOutputStream的图像文件路径时遇到了问题。存在与权限相关的错误。我该如何解决这个问题呢？

if (getIntent().getExtras().getString("file_path") != null) {
    Log.d(TAG, "Path is NOT NULL");
    file = new File(getIntent().getExtras().getString("file_path"));

    Bitmap src;
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(file.getPath(), options);

    final int REQUIRED_SIZE = 400;
    int scale = 1;
    while (options.outWidth / scale / 2 >= REQUIRED_SIZE
            && options.outHeight / scale / 2 >= REQUIRED_SIZE)
        scale *= 2;

    options.inSampleSize = scale;
    options.inJustDecodeBounds = false;
    src = BitmapFactory.decodeFile(file.getAbsolutePath(), options);
    FileOutputStream os;

    try{
        ExifInterface exif = null;
        try {
            exif = new ExifInterface(file.getPath());
        } catch (IOException e) {
            e.printStackTrace();
        }
        int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION,
                ExifInterface.ORIENTATION_UNDEFINED);

        Bitmap bmRotated = rotateBitmap(src, orientation);

        os = new FileOutputStream(file.getAbsoluteFile());
        bmRotated.compress(Bitmap.CompressFormat.JPEG, 100, os);
        photoView.setImageBitmap(bmRotated);
        os.flush();
        os.close();
    } catch (Exception e){
        e.printStackTrace();
    }
} else {
    Log.d(TAG, "Path is NULL");
}

我试着从其他来源寻找，但这对我知道答案没有帮助。

Answer 1

你有没有在清单中声明过这个？我想你错过了android的权限。

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

Answer 2

在AndroidManifest中声明权限时，还需要处理Runtime permissions

Answer 3

将以下权限授予android清单文件..如果执行读取和写入，则同时添加这两个..

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

然后，在活动中，当您执行读写操作时，该定时器将处理运行时权限，如下所示。

 /**
 * this method check permission and return current state of permission need.
 */
private boolean checkPermissions() {
    int permissionState = ActivityCompat.checkSelfPermission(this,
            Manifest.permission.READ_EXTERNAL_STORAGE);
    return permissionState == PackageManager.PERMISSION_GRANTED;
}
  /**
 * this method request to permission asked.
 */

private void requestPermissions() {
    boolean shouldProvideRationale =
            ActivityCompat.shouldShowRequestPermissionRationale(this,
                    Manifest.permission.READ_EXTERNAL_STORAGE);

    if (shouldProvideRationale) {
    } else {
        Log.i("Error", "Requesting permission");
        // previously and checked "Never ask again".
        ActivityCompat.requestPermissions(MainActivity.this,
                new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},
                REQUEST_PERMISSIONS_REQUEST_CODE);
    }
}

然后执行您的操作。

 if (!checkPermissions()) {
        requestPermissions();
    } else {
        // here your operation 
        getFileDetails();

    }

当权限被授予时，则在下面的方法中获得回调。

   @Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    if (requestCode == REQUEST_PERMISSIONS_REQUEST_CODE) {
        if (grantResults.length <= 0) {
            // If user interaction was interrupted, the permission request is cancelled and you
            // receive empty arrays.
            Log.i("Error", "User interaction was cancelled.");
        } else if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            // Permission was granted. Kick off the process of building and connecting
            // GoogleApiClient.
        } else {
        }
    }

}