Question

我正在尝试在xamarin中开发带有Tesseract API的ocr APP（Visual Studio 2019）。我不愿采取这些步骤http://thatcsharpguy.com/posts/tesseract-ocr-in-xamarin-en/。我做了他提到的所有事情。另外，我还在AndriodManifest.xml文件中创建了提供程序路径，但仍然出现文件uri暴露异常。请帮助我，我是xamarin的新手。

AndriodManifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="1" android:versionName="1.0" package="com.companyname.textminer1">
    <uses-sdk android:minSdkVersion="21" android:targetSdkVersion="28" />
    <uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <application android:label="Textminer1.Android">
      <provider android:name="android.support.v4.content.FileProvider"
                android:authorities="com.companyname.textminer1.fileprovider"
                android:exported="false"
                android:grantUriPermissions="true">
        <meta-data android:name="android.support.FILE_PROVIDER_PATHS"
                   android:resource="@xml/file_paths">
        </meta-data>
      </provider>
    </application>

file_paths.xml

<?xml version="1.0" encoding="utf-8" ?>
<paths xmlns:android=" http://schemas.android.com/apk/res/android">
  <external-path name="my_images" path="Android/data/com.companyname.textminer1/files" />
</paths>

MainActivity.cs

var container = TinyIoCContainer.Current;
            container.Register<IDevice>(AndroidDevice.CurrentDevice);

            container.Register<ITesseractApi>((cont, parameters) =>
            {
                return new TesseractApi(ApplicationContext, AssetsDeployment.OncePerInitialization);
            });
            Resolver.SetResolver(new TinyResolver(container));

            LoadApplication(new App());

OCR.xaml.cs

 private async void GetPhotoButton_OnClicked(object sender, EventArgs e)
        {
            if (!_tesseract.Initialized)
                await _tesseract.Init("eng");

            var photo = await TakePic();


            if (photo != null)
            {
                var imageBytes = new byte[photo.Source.Length];
                photo.Source.Position = 0;
                photo.Source.Read(imageBytes, 0, (int)photo.Source.Length);
                photo.Source.Position = 0;

                image.Source = ImageSource.FromStream(() => photo.Source);
                var tessResult = await _tesseract.SetImage(imageBytes);
                if (tessResult)
                {
                    TextLabel.Text = _tesseract.Text;
                }
            }

        }
        private async Task<MediaFile> TakePic()
        {
              var mediaStorageOptions = new CameraMediaStorageOptions
              {
                      DefaultCamera = CameraDevice.Rear,
                      SaveMediaOnCapture = true,
                      Directory = "Picture",
                      Name = string.Format("test.jpg", DateTime.Now.ToString("yyMMddhhmmss")),
                      PercentQuality = 85,
                      MaxPixelDimension = 400

              };
              var mediaFile = await _device.MediaPicker.TakePhotoAsync(mediaStorageOptions);

              return mediaFile;

        }

Android.OS.FileUriExposedException：'file：///storage/emulated/0/Android/data/com.companyname.textminer1/files/Pictures/Picture/test.jpg_1.jpg通过ClipData.Item在应用程序之外公开。 getUri（）'

xamarin-android.os.FileUriExposedException错误

0 个答案: