找不到文件异常（来自URI的路径）

Question

我正在尝试获取用户从图库中选择的图片的FileInputStream对象，但当我尝试打开来自接收到的URI的文件时，它不断显示FileNotFoundException错误信息...

这是我使用的代码来启动从图库选择图像的意图：

Intent intent = new Intent();
    intent.setType("image/*");
    intent.setAction(Intent.ACTION_GET_CONTENT);
    startActivityForResult(Intent.createChooser(intent, "Select Picture"), PICK_IMAGE_REQUEST);

这里是我用来捕获onActivityResult的代码：

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if (requestCode == PICK_IMAGE_REQUEST && resultCode == RESULT_OK && data != null && data.getData() != null) {

        Uri uri = data.getData();
        File myFile = new File(uri.getPath());
        FileInputStream fiStream = new FileInputStream(myFile);
        ...
    }

}

在创建FileInputStream时，我通过模拟器选择一张照片后得到以下错误：

W/System.err: java.io.FileNotFoundException: /document/image:26171: open failed: ENOENT (No such file or directory)

也许我从URI中检索文件的方法不正确？这里需要帮助，非常感谢！

解决方案

最终我使用了https://android-arsenal.com/details/1/2725，它非常易于使用！

- Riptyde4

---

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" /> 我认为你只是忘记添加这个了。 - Keyur Lakhani

@KeyurLakhani 我已经将它添加到我的清单中，但仍然出现相同的错误 :/ - Riptyde4

将Log放在onActivityResult中并检查uri.getPath()是否为空？ - Keyur Lakhani

尝试过使用 ContentResolver#openInputStream 吗？ - pskink

Answer 1

我遇到了完全相同的问题。 我的问题是： 我正在使用这段代码。

        @Override
            public void onActivityResult(int requestCode, int resultCode, Intent data) {
                super.onActivityResult(requestCode, resultCode, data);

                if(requestCode == PICK_IMAGE_REQUEST && resultCode == RESULT_OK && data != null && data.getData() != null){
                    Uri uri = data.getData();
                    try {
                        Bitmap bitmap = MediaStore.Images.Media.getBitmap(getActivity().getContentResolver(), uri);

直到我发现它无法处理更大的图像为止，我不得不改变并使用另一种方法来获取图像。使用InputStream。

            File file= new File(uri.getPath());
            FileInputStream inputStream= new FileInputStream(file);

这是因为路径格式不正确，导致文件未找到异常。

正如Knossos所说：

“您正在尝试打开的Uri是content://document/image:26171。您需要使用ContentProvider访问它。”

感谢Paul Burke提供的库aFileChooser http://github.com/iPaulPro/aFileChooser 为了简化操作，只需创建一个名为FileChooser.java的类即可。

        import android.content.ContentUris;
        import android.content.Context;
        import android.database.Cursor;
        import android.net.Uri;
        import android.os.Build;
        import android.os.Environment;
        import android.provider.DocumentsContract;
        import android.provider.MediaStore;


        public class FileChooser {

            /**
             * Get a file path from a Uri. This will get the the path for Storage Access
             * Framework Documents, as well as the _data field for the MediaStore and
             * other file-based ContentProviders.
             *
             * @param context The context.
             * @param uri The Uri to query.
             * @author paulburke
             */
            public static String getPath(final Context context, final Uri uri) {

                final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;

                // DocumentProvider
                if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
                    // ExternalStorageProvider
                    if (isExternalStorageDocument(uri)) {
                        final String docId = DocumentsContract.getDocumentId(uri);
                        final String[] split = docId.split(":");
                        final String type = split[0];

                        if ("primary".equalsIgnoreCase(type)) {
                            return Environment.getExternalStorageDirectory() + "/" + split[1];
                        }

                        // TODO handle non-primary volumes
                    }
                    // DownloadsProvider
                    else if (isDownloadsDocument(uri)) {

                        final String id = DocumentsContract.getDocumentId(uri);
                        final Uri contentUri = ContentUris.withAppendedId(
                                Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));

                        return getDataColumn(context, contentUri, null, null);
                    }
                    // MediaProvider
                    else if (isMediaDocument(uri)) {
                        final String docId = DocumentsContract.getDocumentId(uri);
                        final String[] split = docId.split(":");
                        final String type = split[0];

                        Uri contentUri = null;
                        if ("image".equals(type)) {
                            contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
                        } else if ("video".equals(type)) {
                            contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
                        } else if ("audio".equals(type)) {
                            contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                        }

                        final String selection = "_id=?";
                        final String[] selectionArgs = new String[] {
                                split[1]
                        };

                        return getDataColumn(context, contentUri, selection, selectionArgs);
                    }
                }
                // MediaStore (and general)
                else if ("content".equalsIgnoreCase(uri.getScheme())) {
                    return getDataColumn(context, uri, null, null);
                }
                // File
                else if ("file".equalsIgnoreCase(uri.getScheme())) {
                    return uri.getPath();
                }

                return null;
            }

            /**
             * Get the value of the data column for this Uri. This is useful for
             * MediaStore Uris, and other file-based ContentProviders.
             *
             * @param context The context.
             * @param uri The Uri to query.
             * @param selection (Optional) Filter used in the query.
             * @param selectionArgs (Optional) Selection arguments used in the query.
             * @return The value of the _data column, which is typically a file path.
             */
            public static String getDataColumn(Context context, Uri uri, String selection,
                                               String[] selectionArgs) {

                Cursor cursor = null;
                final String column = "_data";
                final String[] projection = {
                        column
                };

                try {
                    cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs,
                            null);
                    if (cursor != null && cursor.moveToFirst()) {
                        final int column_index = cursor.getColumnIndexOrThrow(column);
                        return cursor.getString(column_index);
                    }
                } finally {
                    if (cursor != null)
                        cursor.close();
                }
                return null;
            }


            /**
             * @param uri The Uri to check.
             * @return Whether the Uri authority is ExternalStorageProvider.
             */
            public static boolean isExternalStorageDocument(Uri uri) {
                return "com.android.externalstorage.documents".equals(uri.getAuthority());
            }

            /**
             * @param uri The Uri to check.
             * @return Whether the Uri authority is DownloadsProvider.
             */
            public static boolean isDownloadsDocument(Uri uri) {
                return "com.android.providers.downloads.documents".equals(uri.getAuthority());
            }

            /**
             * @param uri The Uri to check.
             * @return Whether the Uri authority is MediaProvider.
             */
            public static boolean isMediaDocument(Uri uri) {
                return "com.android.providers.media.documents".equals(uri.getAuthority());
            }
        }

然后我们可以在我们的活动结果中简单地访问它。

        @Override
            public void onActivityResult(int requestCode, int resultCode, Intent data) {
                super.onActivityResult(requestCode, resultCode, data);

                if(requestCode == PICK_IMAGE_REQUEST && resultCode == RESULT_OK && data != null && data.getData() != null){
                    Uri uri = data.getData();
                    try {
                        InputStream in = new FileInputStream(FileChooser.getPath(getContext(),uri));

由于我想在使用图像之前调整其大小，所以这是完整的代码...希望能对某些人有所帮助...;) 感谢blubl。

@Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if(requestCode == PICK_IMAGE_REQUEST && resultCode == RESULT_OK && data != null && data.getData() != null){
        Uri uri = data.getData();
        try {
            /*Bitmap bitmap = MediaStore.Images.Media.getBitmap(getActivity().getContentResolver(), uri);*/

            InputStream in = new FileInputStream(FileChooser.getPath(getContext(),uri));

            int dstWidth = 1980;
            int dstHeight = 960;
            int inWidth, inHeight;

            //get image size
            BitmapFactory.Options options = new BitmapFactory.Options();
            options.inJustDecodeBounds = true;
            BitmapFactory.decodeStream(in, null, options);
            in.close();

            inWidth = options.outWidth;
            inHeight = options.outHeight;

            in = new FileInputStream(FileChooser.getPath(getContext(),uri));
            options = new BitmapFactory.Options();
            // decode full image pre resized
            options.inSampleSize = Math.max(inWidth/dstWidth, inHeight/dstHeight);

            Bitmap roughtBitmap = BitmapFactory.decodeStream(in, null, options);

            Matrix m = new Matrix();
            RectF inRect = new RectF(0, 0, roughtBitmap.getWidth(), roughtBitmap.getHeight());
            RectF outRectF = new RectF(0, 0, dstWidth, dstHeight);
            m.setRectToRect(inRect, outRectF, Matrix.ScaleToFit.CENTER);
            float[] values = new float[9];
            m.getValues(values);

            Bitmap resizedBitmap = Bitmap.createScaledBitmap(roughtBitmap, (int)(roughtBitmap.getWidth() * values[0]), (int)(roughtBitmap.getHeight() * values[4]), true);

            currentQrItem.setPicture(resizedBitmap);
            adapter.changeImage(currentQrItem);
        }catch (IOException e){
            e.printStackTrace();
        }
    }
}

- Napster Scofield

---

我正在使用相同的方法。它之前对我完美地起作用，但现在出现了错误。" Caused by: java.lang.NumberFormatException: For input string: "raw:/storage/emulated/0/Download/Images/405435.jpg" " at line final Uri contentUri = ContentUris.withAppendedId( Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));我的目标SDK是29，我正在使用运行时权限。 - Narayan C.R

Answer 2

这里的问题是您试图像访问文件一样访问内容Uri。

您试图打开的Uri是content://document/image:26171。您需要使用ContentProvider来访问它。

有一个很好的Stack Overflow答案可以帮助您完成这个操作。

- Knossos

Answer 3

Intent intent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
                    intent.setType("image/*");
                    startActivityForResult(Intent.createChooser(intent, "Select File"), SELECT_FILE);

在onActivityResult方法中。

Uri selectedImageUri = data.getData();
                String[] projection = { MediaStore.MediaColumns.DATA };
                CursorLoader cursorLoader = new CursorLoader(this,selectedImageUri, projection, null, null,null);
                Cursor cursor =cursorLoader.loadInBackground();
                int column_index = cursor.getColumnIndexOrThrow(MediaStore.MediaColumns.DATA);
                cursor.moveToFirst();
                String selectedImagePath = cursor.getString(column_index);

                BitmapFactory.Options options = new BitmapFactory.Options();
                options.inJustDecodeBounds = true;
                final int REQUIRED_SIZE = 200;
                int scale = 1;
                while (options.outWidth / scale / 2 >= REQUIRED_SIZE
                        && options.outHeight / scale / 2 >= REQUIRED_SIZE)
                    scale *= 2;
                options.inSampleSize = scale;
                options.inJustDecodeBounds = false;
                Bitmap bitmap = BitmapFactory.decodeFile(selectedImagePath, options);

- Pavya

---

我在这里的目标是将文件转换为字节数组，因此FileInputStream可能更合适，但我会尝试使用您的意图设置并查看发生了什么。您知道直接从URI转换为File的正确方法吗？ - Riptyde4

为什么这有帮助？仅仅给出代码答案并不能帮助提问者学习。 - Knossos

使用以下代码：File myFile = new File(selectedImagePath); 然后添加您的代码。 - Pavya

你介意简要介绍一下这里发生了什么吗？ - Riptyde4

这将导致一张空白的图片 :/ - Riptyde4

Answer 4

你的目标是23 SDK版本吗？如果是，你必须获取READ_EXTERNAL_STORAGE的运行时权限。

- Thahaseen

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最好在评论区中进行帖子的澄清。 - Debosmit Ray

Answer 5

我曾经遇到同样的问题，后来在这里找到了答案：

如何使用Intent.ACTION_CREATE_DOCUMENT编写文件

只需使用getContentResolver().openInputStream(uri)来创建输入流，而不是使用filePath。

- Flyview