java – 如何在Android API 19(KitKat)中持久许可？

在我的应用程序中,我将图像的路径存储在我的sqlite数据库中以供进一步使用.我得到的路径是

content://com.android.providers.media.documents/document/image%3A71964

当我从数据库中检索该路径并尝试从该路径中检索图像时,android throws

java.lang.SecurityException: Permission Denial: opening provider
com.android.providers.media.MediaDocumentsProvider 
from ProcessRecord{42c84ec8 23911:com.gots.gb/u0a248} (pid=23911,uid=10248) 
requires android.permission.MANAGE_DOCUMENTS or android.permission.MANAGE_DOCUMENTS

根据https://developer.android.com/guide/topics/providers/document-provider.html#permissions我需要持续许可通过添加以下代码

final int takeFlags = intent.getFlags()
        & (Intent.FLAG_GRANT_READ_URI_PERMISSION
        | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
// Check for the freshest data.
getContentResolver().takePersistableuriPermission(uri,takeFlags);

当我添加这个代码到我的ImageAdapter类,它扩展了BaseAdapter android throws

08-21 02:14:38.530: W/System.err(24452): java.lang.SecurityException:
No permission grant found for UID 10248 and Uri 
content://com.android.providers.media.documents/document/image:71964

这是我的ImageAdapter代码的相关部分

public View getView(int position,View convertView,ViewGroup parent) {
    ImageView imageView ;


    if (convertView == null){
        imageView = new ImageView(mContext);
        imageView.setLayoutParams(new GridView.LayoutParams(185,185));
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setPadding(8,8,8);

    }
    else{
        imageView = (ImageView)convertView ;
    }

    InputStream is = null;
    Bitmap bitmap = null ;

    try {

        Log.d(TAG,String.valueOf(list.get(position)));
        Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
        final int takeFlags = intent.getFlags()
                & (Intent.FLAG_GRANT_READ_URI_PERMISSION
                | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
        // Check for the freshest data.

        if (Build.VERSION.SDK_INT >= 19){
            mContext.getContentResolver().takePersistableuriPermission(list.get(position),takeFlags);
        }


        is = mContext.getContentResolver().openInputStream(list.get(position));

        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inSampleSize = 8;
        bitmap = BitmapFactory.decodeStream(is,null,options);
        is.close();
        imageView.setimageBitmap(bitmap);

        return imageView;

    }
    catch (Exception e) {
        e.printstacktrace();

        return null;
    }

我究竟做错了什么？
谢谢

解决方法

我相信我已经解决了.请求意图：

Intent intent;
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT){
    intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
    intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE,true);
    intent.addFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION);
}else{
    intent = new Intent(Intent.ACTION_GET_CONTENT);
}
intent.putExtra(Intent.EXTRA_LOCAL_ONLY,true);
intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
intent.setType("image/*");
startActivityForResult(Intent.createChooser(intent,getResources().getString(R.string.form_pick_photos)),REQUEST_PICK_PHOTO);

和onActivityResult

...
// kitkat fixed (broke) content access; to keep the URIs valid over restarts need to persist access permission
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
    final int takeFlags = data.getFlags() & Intent.FLAG_GRANT_READ_URI_PERMISSION;
    ContentResolver resolver = getActivity().getContentResolver();
    for (Uri uri : images) {
        resolver.takePersistableuriPermission(uri,takeFlags);
    }
}
...

我没有测试过这个pre-kitkat,我的手机正在运行5.1,任何人都可以在旧的手机上验证这个？