android开发:如何获取非sd卡里的图片

在android开发分享功能的时候遇到图片的位置在system/media/image/里面，或者给了content://com.zhihu.android.provider.image…这样的uri时，无法获取图片路径，请问各位大神有知道如何解决的吗？

试试这个工具类。
public class FileHelper {
public static String getRealPath(Uri uri, Activity mActivity) {
String realPath = null;

    if (Build.VERSION.SDK_INT < 11)
        realPath = FileHelper.getRealPathFromURI_BelowAPI11(mActivity, uri);

        // SDK >= 11
    else
        realPath = FileHelper.getRealPathFromURI_API11_And_Above(mActivity, uri);

    return realPath;
}

public static String getRealPath(String uriString, Activity mActivity) {
    return FileHelper.getRealPath(Uri.parse(uriString), mActivity);
}

@SuppressLint("NewApi")
public static String getRealPathFromURI_API11_And_Above(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;
}

public static String getRealPathFromURI_BelowAPI11(Context context, Uri contentUri) {
    String[] proj = {MediaStore.Images.Media.DATA};
    String result = null;

    try {
        Cursor cursor = context.getContentResolver().query(contentUri, proj, null, null, null);
        int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
        cursor.moveToFirst();
        result = cursor.getString(column_index);

    } catch (Exception e) {
        result = null;
    }
    return result;
}


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);
        }
    } catch (Exception e) {
        return null;
    } finally {
        if (cursor != null)
            cursor.close();
    }
    return null;
}

public static boolean isExternalStorageDocument(Uri uri) {
    return "com.android.externalstorage.documents".equals(uri.getAuthority());
}

public static boolean isDownloadsDocument(Uri uri) {
    return "com.android.providers.downloads.documents".equals(uri.getAuthority());
}

public static boolean isMediaDocument(Uri uri) {
    return "com.android.providers.media.documents".equals(uri.getAuthority());
}

public static boolean isGooglePhotosUri(Uri uri) {
    return "com.google.android.apps.photos.content".equals(uri.getAuthority());
}

}