Android 4.4(KitKat)上的Android Gallery为Intent.ACTION_GET_CONTENT返回不同的URI

Question

在KitKat之前(或在新Gallery之前)Intent.ACTION_GET_CONTENT返回这样的URI

内容://媒体/外部/图像/媒体/ 3951.

使用ContentResolver和quering MediaStore.Images.Media.DATA返回文件URL.

但是在KitKat中,Gallery会返回一个URI(通过"Last"),如下所示:

内容://com.android.providers.media.documents/document/image:3951

我该如何处理？

Answer 1

这不需要特殊权限,并且可以使用Storage Access Framework以及非官方ContentProvider模式(_data字段中的文件路径).

/**
 * 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 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());
}

在此处查看此方法的最新版本.

Answer 2

试试这个:

if (Build.VERSION.SDK_INT <19){
    Intent intent = new Intent(); 
    intent.setType("image/jpeg");
    intent.setAction(Intent.ACTION_GET_CONTENT);
    startActivityForResult(Intent.createChooser(intent, getResources().getString(R.string.select_picture)),GALLERY_INTENT_CALLED);
} else {
    Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
    intent.addCategory(Intent.CATEGORY_OPENABLE);
    intent.setType("image/jpeg");
    startActivityForResult(intent, GALLERY_KITKAT_INTENT_CALLED);
}

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode != Activity.RESULT_OK) return;
    if (null == data) return;
    Uri originalUri = null;
    if (requestCode == GALLERY_INTENT_CALLED) {
        originalUri = data.getData();
    } else if (requestCode == GALLERY_KITKAT_INTENT_CALLED) {
        originalUri = data.getData();
        final int takeFlags = data.getFlags()
                & (Intent.FLAG_GRANT_READ_URI_PERMISSION
                | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
        // Check for the freshest data.
        getContentResolver().takePersistableUriPermission(originalUri, takeFlags);
    }

    loadSomeStreamAsynkTask(originalUri);

}

可能需要

@SuppressLint( "NewApi")

对于

takePersistableUriPermission

Answer 3

有同样的问题,尝试了上面的解决方案,但虽然它一般工作,由于某种原因我得到权限拒绝Uri内容提供商的一些图像虽然我已android.permission.MANAGE_DOCUMENTS正确添加权限.

无论如何找到其他解决方案,强制打开图像库而不是KITKAT文档视图:

// KITKAT

i = new Intent(Intent.ACTION_PICK,android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
    startActivityForResult(i, CHOOSE_IMAGE_REQUEST);

然后加载图像:

Uri selectedImageURI = data.getData();
input = c.getContentResolver().openInputStream(selectedImageURI);
                BitmapFactory.decodeStream(input , null, opts);

编辑

ACTION_OPEN_DOCUMENT 可能要求您持久保存权限标志等,并且通常会导致安全例外...

其他解决方案是使用ACTION_GET_CONTENT组合使用c.getContentResolver().openInputStream(selectedImageURI)它将在pre-KK和KK上工作.Kitkat将使用新的文档视图,此解决方案将适用于所有应用程序,如照片,图库,文件资源管理器,Dropbox,谷歌驱动器等...)但请记住,使用此解决方案时,您必须在您的图像中创建图像onActivityResult()并将其存储在例如SD卡.即使您添加了Google API文档中描述的权限标记(在我进行某些测试时发生的情况),在下次应用启动时从已保存的uri重新创建此图像也会在内容解析器上引发安全例外

此外,Android Developer API指南建议:

ACTION_OPEN_DOCUMENT不能替代ACTION_GET_CONTENT.您应该使用的那个取决于您的应用程序的需求:

如果您希望应用程序只读取/导入数据,请使用ACTION_GET_CONTENT.使用此方法,应用程序将导入数据的副本,例如图像文件.

如果您希望应用程序对文档提供程序拥有的文档具有长期,持久的访问权限,请使用ACTION_OPEN_DOCUMENT.一个例子是照片编辑应用程序,它允许用户编辑存储在文档提供程序中的图像.

Answer 4

就像Commonsware提到的那样,你不应该假设你通过的流可以ContentResolver转换成文件.

你真正应该做的是从中打开,然后InputStream从中ContentProvider创建一个Bitmap.它适用于4.4及更早版本,无需反射.

    //cxt -> current context

    InputStream input;
    Bitmap bmp;
    try {
        input = cxt.getContentResolver().openInputStream(fileUri);
        bmp = BitmapFactory.decodeStream(input);
    } catch (FileNotFoundException e1) {

    }

当然,如果你处理大图像,你应该用适当的方法加载它们inSampleSize:http://developer.android.com/training/displaying-bitmaps/load-bitmap.html.但这是另一个话题.

Answer 5

我相信已经发布的回复应该让人们朝着正确的方向前进.但是,我所做的就是我正在更新的遗留代码.遗留代码使用库中的URI来更改然后保存图像.

在4.4(和谷歌驱动器)之前,URI将如下所示: content:// media/external/images/media/41

正如问题中所述,它们通常看起来像这样: content://com.android.providers.media.documents/document/image:3951

由于我需要能够保存图像而不会干扰现有代码,因此我只是将图库中的URI复制到应用程序的数据文件夹中.然后从数据文件夹中保存的图像文件中生成一个新的URI.

这是个主意:

Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(intent), CHOOSE_IMAGE_REQUEST);

public void onActivityResult(int requestCode, int resultCode, Intent data) {

    super.onActivityResult(requestCode, resultCode, data);

    File tempFile = new File(this.getFilesDir().getAbsolutePath(), "temp_image");

    //Copy URI contents into temporary file.
    try {
        tempFile.createNewFile();
        copyAndClose(this.getContentResolver().openInputStream(data.getData()),new FileOutputStream(tempFile));
    }
    catch (IOException e) {
        //Log Error
    }

    //Now fetch the new URI
    Uri newUri = Uri.fromFile(tempFile);

    /* Use new URI object just like you used to */
 }

注意 - copyAndClose()只执行文件I/O以将InputStream复制到FileOutputStream中.代码未发布.

Answer 6

只是想说这个答案很棒,而且我已经使用了很长时间没有问题.但前段时间我偶然发现了一个问题,即DownloadsProvider以格式返回URI content://com.android.providers.downloads.documents/document/raw%3A%2Fstorage%2Femulated%2F0%2FDownload%2Fdoc.pdf,因此应用程序崩溃,NumberFormatException因为无法解析其uri段.但是raw:段包含直接uri,可用于检索引用的文件.所以我通过用isDownloadsDocument(uri) if以下内容替换内容来修复它:

final String id = DocumentsContract.getDocumentId(uri);
if (!TextUtils.isEmpty(id)) {
if (id.startsWith("raw:")) {
    return id.replaceFirst("raw:", "");
}
try {
    final Uri contentUri = ContentUris.withAppendedId(
            Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
    return getDataColumn(context, contentUri, null, null);
} catch (NumberFormatException e) {
    Log.e("FileUtils", "Downloads provider returned unexpected uri " + uri.toString(), e);
    return null;
}
}

Answer 7

我将多个答案组合成一个使用文件路径的工作解决方案

Mime类型与示例目的无关.

            Intent intent;
            if(Build.VERSION.SDK_INT >= 19){
                intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
                intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, false);
                intent.addFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION);
            }else{
                intent = new Intent(Intent.ACTION_GET_CONTENT);
            }
            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
            intent.setType("application/octet-stream");
            if(isAdded()){
                startActivityForResult(intent, RESULT_CODE);
            }

处理结果

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
    if( requestCode == RESULT_CODE && resultCode == Activity.RESULT_OK) {
        Uri uri = data.getData();
        if (uri != null && !uri.toString().isEmpty()) {
            if(Build.VERSION.SDK_INT >= 19){
                final int takeFlags = data.getFlags() & Intent.FLAG_GRANT_READ_URI_PERMISSION;
                //noinspection ResourceType
                getActivity().getContentResolver()
                        .takePersistableUriPermission(uri, takeFlags);
            }
            String filePath = FilePickUtils.getSmartFilePath(getActivity(), uri);
            // do what you need with it...
        }
    }
}

FilePickUtils

import android.annotation.SuppressLint;
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 FilePickUtils {
    private static String getPathDeprecated(Context ctx, Uri uri) {
        if( uri == null ) {
            return null;
        }
        String[] projection = { MediaStore.Images.Media.DATA };
        Cursor cursor = ctx.getContentResolver().query(uri, projection, null, null, null);
        if( cursor != null ){
            int column_index = cursor
                    .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
            cursor.moveToFirst();
            return cursor.getString(column_index);
        }
        return uri.getPath();
    }

    public static String getSmartFilePath(Context ctx, Uri uri){

        if (Build.VERSION.SDK_INT < 19) {
            return getPathDeprecated(ctx, uri);
        }
        return  FilePickUtils.getPath(ctx, uri);
    }

    @SuppressLint("NewApi")
    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());
    }

}

Answer 8

题

如何从URI获取实际文件路径

回答

据我所知,我们不需要从URI获取文件路径,因为对于大多数情况,我们可以直接使用URI来完成我们的工作(例如1.获取位图2.将文件发送到服务器等.)

1.发送到服务器

我们可以使用URI直接将文件发送到服务器.

使用URI我们可以获得InputStream,我们可以使用MultiPartEntity直接将其发送到服务器.

例

/**
 * Used to form Multi Entity for a URI (URI pointing to some file, which we got from other application).
 *
 * @param uri     URI.
 * @param context Context.
 * @return Multi Part Entity.
 */
public MultipartEntity formMultiPartEntityForUri(final Uri uri, final Context context) {
    MultipartEntity multipartEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE, null, Charset.forName("UTF-8"));
    try {
        InputStream inputStream = mContext.getContentResolver().openInputStream(uri);
        if (inputStream != null) {
            ContentBody contentBody = new InputStreamBody(inputStream, getFileNameFromUri(uri, context));
            multipartEntity.addPart("[YOUR_KEY]", contentBody);
        }
    }
    catch (Exception exp) {
        Log.e("TAG", exp.getMessage());
    }
    return multipartEntity;
}

/**
 * Used to get a file name from a URI.
 *
 * @param uri     URI.
 * @param context Context.
 * @return File name from URI.
 */
public String getFileNameFromUri(final Uri uri, final Context context) {

    String fileName = null;
    if (uri != null) {
        // Get file name.
        // File Scheme.
        if (ContentResolver.SCHEME_FILE.equals(uri.getScheme())) {
            File file = new File(uri.getPath());
            fileName = file.getName();
        }
        // Content Scheme.
        else if (ContentResolver.SCHEME_CONTENT.equals(uri.getScheme())) {
            Cursor returnCursor =
                    context.getContentResolver().query(uri, null, null, null, null);
            if (returnCursor != null && returnCursor.moveToFirst()) {
                int nameIndex = returnCursor.getColumnIndex(OpenableColumns.DISPLAY_NAME);
                fileName = returnCursor.getString(nameIndex);
                returnCursor.close();
            }
        }
    }
    return fileName;
}

2.从URI获取BitMap

如果URI指向图像,那么我们将得到位图,否则为null:

/**
 * Used to create bitmap for the given URI.
 * <p>
 * 1. Convert the given URI to bitmap.
 * 2. Calculate ratio (depending on bitmap size) on how much we need to subSample the original bitmap.
 * 3. Create bitmap bitmap depending on the ration from URI.
 * 4. Reference - http://stackoverflow.com/questions/3879992/how-to-get-bitmap-from-an-uri
 *
 * @param context       Context.
 * @param uri           URI to the file.
 * @param bitmapSize Bitmap size required in PX.
 * @return Bitmap bitmap created for the given URI.
 * @throws IOException
 */
public static Bitmap createBitmapFromUri(final Context context, Uri uri, final int bitmapSize) throws IOException {

    // 1. Convert the given URI to bitmap.
    InputStream input = context.getContentResolver().openInputStream(uri);
    BitmapFactory.Options onlyBoundsOptions = new BitmapFactory.Options();
    onlyBoundsOptions.inJustDecodeBounds = true;
    onlyBoundsOptions.inDither = true;//optional
    onlyBoundsOptions.inPreferredConfig = Bitmap.Config.ARGB_8888;//optional
    BitmapFactory.decodeStream(input, null, onlyBoundsOptions);
    input.close();
    if ((onlyBoundsOptions.outWidth == -1) || (onlyBoundsOptions.outHeight == -1)) {
        return null;
    }

    // 2. Calculate ratio.
    int originalSize = (onlyBoundsOptions.outHeight > onlyBoundsOptions.outWidth) ? onlyBoundsOptions.outHeight : onlyBoundsOptions.outWidth;
    double ratio = (originalSize > bitmapSize) ? (originalSize / bitmapSize) : 1.0;

    // 3. Create bitmap.
    BitmapFactory.Options bitmapOptions = new BitmapFactory.Options();
    bitmapOptions.inSampleSize = getPowerOfTwoForSampleRatio(ratio);
    bitmapOptions.inDither = true;//optional
    bitmapOptions.inPreferredConfig = Bitmap.Config.ARGB_8888;//optional
    input = context.getContentResolver().openInputStream(uri);
    Bitmap bitmap = BitmapFactory.decodeStream(input, null, bitmapOptions);
    input.close();

    return bitmap;
}

/**
 * For Bitmap option inSampleSize - We need to give value in power of two.
 *
 * @param ratio Ratio to be rounded of to power of two.
 * @return Ratio rounded of to nearest power of two.
 */
private static int getPowerOfTwoForSampleRatio(final double ratio) {
    int k = Integer.highestOneBit((int) Math.floor(ratio));
    if (k == 0) return 1;
    else return k;
}

评论

1. Android没有提供从URI获取文件路径的任何方法,并且在上面的大多数答案中,我们对一些常量进行了硬编码,这可能会破坏功能发布(抱歉,我可能错了).
2. 在直接从URI获取文件路径的解决方案之前,请尝试使用URI和Android默认方法解决您的用例.

参考

1. https://developer.android.com/guide/topics/providers/content-provider-basics.html
2. https://developer.android.com/reference/android/content/ContentResolver.html
3. https://hc.apache.org/httpcomponents-client-ga/httpmime/apidocs/org/apache/http/entity/mime/content/InputStreamBody.html

Answer 9

这个Android库处理KitKat中的大小写更改(包括oldere版本 - 2.1+):https:
//github.com/iPaulPro/aFileChooser

使用该String path = FileUtils.getPath(context, uri)命令将返回的Uri转换为可在所有OS版本上使用的路径字符串.在此处查看更多相关信息:https://stackoverflow.com/a/20559175/860488