我有一个onActivityResult从一个mediastore图像选择返回,我可以获得一个图像使用以下URI:

Uri selectedImage = data.getData();

将this转换为字符串会得到:

content://media/external/images/media/47

或路径给出:

/external/images/media/47

然而,我似乎找不到一种方法将其转换为绝对路径,因为我想将图像加载到位图中,而不必复制到某个地方。我知道这可以使用URI和内容解析器来完成,但这似乎在重新启动手机时中断,我猜MediaStore在重新启动之间没有保持其编号相同。


当前回答

现在事情变得复杂了,尤其是在API级别为29的Android Q之后。

You must requestLegacyStorage in the manifest.xml. This is how you should get filename from the content Uri public static String getNameFromContentUri(Context context, Uri contentUri){ Cursor returnCursor = context.getContentResolver().query(contentUri, null, null, null, null); int nameColumnIndex = returnCursor.getColumnIndex(OpenableColumns.DISPLAY_NAME); returnCursor.moveToFirst(); String fileName = returnCursor.getString(nameColumnIndex); return fileName;} and this is how you get full path of the Content Uri for all android versions

JAVA

    public static String getFullPathFromContentUri(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 ("com.android.externalstorage.documents".equals(uri.getAuthority())) {
                    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];
                    }//non-primary e.g sd card
                     else {

                           if (Build.VERSION.SDK_INT > 20) {
                    //getExternalMediaDirs() added in API 21
                    File extenal[] = context.getExternalMediaDirs();
                   for (File f : extenal) {
                    filePath = f.getAbsolutePath();
                    if (filePath.contains(type)) {
                        int endIndex = filePath.indexOf("Android");
                        filePath = filePath.substring(0, endIndex) + split[1];
                    }
                }
             }else{
                    filePath = "/storage/" + type + "/" + split[1];
             }
            return filePath;
        }
                }
                // DownloadsProvider
                else if ("com.android.providers.downloads.documents".equals(uri.getAuthority())) {
    
                    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 ("com.android.providers.media.documents".equals(uri.getAuthority())) {
                    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]
                    };
    
                       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;
                }
            }
            // 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;
        }

    private 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;
        }

科特林

companion object {
@JvmStatic
    @SuppressLint("NewApi")
    fun getPath(context: Context, uri: Uri): String? {
        val isKitKat: Boolean = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT

        // DocumentProvider
        if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
            // ExternalStorageProvider
            if (isExternalStorageDocument(uri)) {
                val docId = DocumentsContract.getDocumentId(uri)
                val split = docId.split(":").toTypedArray()
                val type = split[0]
                return if ("primary".equals(type, ignoreCase = true)) {
                    Environment.getExternalStorageDirectory().toString() + "/" + split[1]
                } else { // non-primary volumes e.g sd card
                    var filePath = "non"
                    //getExternalMediaDirs() added in API 21
                    val extenal = context.externalMediaDirs
                    for (f in extenal) {
                        filePath = f.absolutePath
                        if (filePath.contains(type)) {
                            val endIndex = filePath.indexOf("Android")
                            filePath = filePath.substring(0, endIndex) + split[1]
                        }
                    }
                    filePath
                }
            } else if (isDownloadsDocument(uri)) {
                val id = DocumentsContract.getDocumentId(uri)
                val contentUri = ContentUris.withAppendedId(
                        Uri.parse("content://downloads/public_downloads"), java.lang.Long.valueOf(id))
                return getDataColumn(context, contentUri, null, null)
            } else if (isMediaDocument(uri)) {
                val docId = DocumentsContract.getDocumentId(uri)
                val split = docId.split(":").toTypedArray()
                val type = split[0]
                var contentUri: Uri? = null
                if ("image" == type) {
                    contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI
                } else if ("video" == type) {
                    contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI
                } else if ("audio" == type) {
                    contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI
                }
                val selection = "_id=?"
                val selectionArgs = arrayOf(
                        split[1]
                )
                return getDataColumn(context, contentUri, selection, selectionArgs)
            }
        } else if ("content".equals(uri.scheme, ignoreCase = true)) {
            return getDataColumn(context, uri, null, null)
        } else if ("file".equals(uri.scheme, ignoreCase = true)) {
            return uri.path
        }
        return null
    }

    private fun getDataColumn(context: Context, uri: Uri?, selection: String?,
                              selectionArgs: Array<String>?): String? {
        var cursor: Cursor? = null
        val column = "_data"
        val projection = arrayOf(
                column
        )
        try {
            cursor = context.contentResolver.query(uri!!, projection, selection, selectionArgs,
                    null)
            if (cursor != null && cursor.moveToFirst()) {
                val column_index = cursor.getColumnIndexOrThrow(column)
                return cursor.getString(column_index)
            }
        } catch (e: java.lang.Exception) {
        } finally {
            cursor?.close()
        }
        return null
    }

    private fun isExternalStorageDocument(uri: Uri): Boolean {
        return "com.android.externalstorage.documents" == uri.authority
    }

    private fun isDownloadsDocument(uri: Uri): Boolean {
        return "com.android.providers.downloads.documents" == uri.authority
    }

    private fun isMediaDocument(uri: Uri): Boolean {
        return "com.android.providers.media.documents" == uri.authority
    }

}

}

其他回答

如果你的系统版本在19以上,这对我来说是完美的,希望这能帮助你。

  @TargetApi(Build.VERSION_CODES.KITKAT)
    public static String getPath(final Context context, final Uri uri) {
        final boolean isOverKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
        // DocumentProvider
        if (isOverKitKat && 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];
                }
            }
            // 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;
    }

我是这样做的:

    Uri queryUri = MediaStore.Files.getContentUri("external");
    String columnData = MediaStore.Files.FileColumns.DATA;
    String columnSize = MediaStore.Files.FileColumns.SIZE;

    String[] projectionData = {MediaStore.Files.FileColumns.DATA};


    String name = null;
    String size = null;

    Cursor cursor = getContentResolver().query(contentURI, null, null, null, null);
    if ((cursor != null)&&(cursor.getCount()>0)) {
        int nameIndex = cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME);
        int sizeIndex = cursor.getColumnIndex(OpenableColumns.SIZE);

        cursor.moveToFirst();

        name = cursor.getString(nameIndex);
        size = cursor.getString(sizeIndex);

        cursor.close();
    }

    if ((name!=null)&&(size!=null)){
        String selectionNS = columnData + " LIKE '%" + name + "' AND " +columnSize + "='" + size +"'";

        Cursor cursorLike = getContentResolver().query(queryUri, projectionData, selectionNS, null, null);

        if ((cursorLike != null)&&(cursorLike.getCount()>0)) {
            cursorLike.moveToFirst();
            int indexData = cursorLike.getColumnIndex(columnData);
            if (cursorLike.getString(indexData) != null) {
                result = cursorLike.getString(indexData);
            }
            cursorLike.close();
        }
    }

    return result;

不要尝试在文件系统中查找uri,那样在数据库中查找东西会很慢。

你可以通过给工厂一个输入流来从uri中获得位图,就像给工厂一个文件一样:

InputStream is = getContentResolver().openInputStream(uri);
Bitmap bitmap = BitmapFactory.decodeStream(is);
is.close();

Bitmap Bitmap = MediaStore.Images.Media.getBitmap, uri;

既然上面的答案对我不起作用,下面是对我有效的解决方案:

对于>19和<=19 API级别。

这个方法涵盖了从uri中获取filePath的所有情况

/**
 * 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 activity.
 * @param uri The Uri to query.
 * @author paulburke
 */
public static String getPath(final Context context, final Uri uri) {

    // DocumentProvider
    if ( Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT && 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];
            }else{
                Toast.makeText(context, "Could not get file path. Please try again", Toast.LENGTH_SHORT).show();
            }
        }
        // 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;
            } else {
                contentUri = MediaStore.Files.getContentUri("external");
            }

            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;
}