Question

我正在从图库中选择图像，但以下代码段会创建FileNotFoundException。代码很好，但我不知道它为什么会引发异常。提前致谢

这是Logcat消息：

无法解码流：java.io.FileNotFoundException：/storage/emulated/0/Pictures/Screenshots/Screenshot_2015-09-15-17-27-49.png：open failed：EACCES（Permission denied）

以下是我的代码

 protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if(requestCode==0010 && resultCode== RESULT_OK && data!=null)
        {
            Uri selectedImage = data.getData();
            String[] filePathColumn = { MediaStore.Images.Media.DATA };

            Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);
            cursor.moveToFirst();

            int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
            String imgDecodableString = cursor.getString(columnIndex);
            cursor.close();

            Testing = (ImageView) findViewById(R.id.testing);
            // Set the Image in ImageView after decoding the String
            Testing.setImageBitmap(BitmapFactory.decodeFile(imgDecodableString));

        } else {
            Utility.message(EditProfileActivity.this, "You've not picked image");
        }
    }

Answer 1

最好使用下面的类来返回文件路径。无论你选择哪个地方都没关系。你的代码有时会失败，例如，如果你从谷歌驱动器中选择你可能没有得到上述代码的路径。退房..

import android.annotation.TargetApi;
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 FetchPath {
    /**
     * 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
     */
    @TargetApi(Build.VERSION_CODES.KITKAT)
    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 the remote address
            if (isGooglePhotosUri(uri))
                return uri.getLastPathSegment();

            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 index = cursor.getColumnIndexOrThrow(column);
                return cursor.getString(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());
    }

    /**
     * @param uri The Uri to check.
     * @return Whether the Uri authority is Google Photos.
     */
    public static boolean isGooglePhotosUri(Uri uri) {
        return "com.google.android.apps.photos.content".equals(uri.getAuthority());
    }

}

用法

 Uri photoUri = data.getData();
 if (photoUri != null) {
 String filePath = FetchPath.getPath(this, photoUri);
  }

图库意图

 Intent photoPickerIntent = new Intent(Intent.ACTION_PICK);
 photoPickerIntent.setType("image/*");
 startActivityForResult(photoPickerIntent, requestCode);

Answer 2

在清单中加上一行

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

Answer 3

您可能无法向清单添加所需权限，添加用户读取外部存储空间的权限

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

Answer 4

我有与此相同的问题。我的代码整夜都在工作，然后在早晨醒来之后似乎再也没有工作了。我什至设置了所有东西：

意图

Intent photoPickerIntent = new Intent(Intent.ACTION_PICK);
photoPickerIntent.setType("image/*");

// Ensure that there's a gallery to handle the intent
if (photoPickerIntent.resolveActivity(getPackageManager()) != null) {
    // Launch the gallery
    startActivityForResult(photoPickerIntent, REQUEST_IMAGE_GALLERY);

}

onActivityResult：

Uri imageUri = data.getData();

InputStream imageStream = getContentResolver().openInputStream(imageUri);

mResultsBitmap = BitmapFactory.decodeStream(imageStream);

清单文件：

uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"

uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"

所以我想我昨晚就知道了，然后今天早上什么也没用。.解决方案：我去了三星设置->设备维护->内存，然后->存储。我开始清理内存，系统再次运行。

似乎这与内存不足有关，因为我只有16GB的总内存，只剩下了几GB

从图库中选择图像时出现FileNotFoundException

4 个答案: