Permission Denial while sharing file with FileProvider

问题

I am trying to share file with FileProvider. I checked that file is shared properly with apps like gmail, google drive etc. Even though following exception is thrown:

2019-08-28 11:43:03.169 12573-12595/com.example.name E/DatabaseUtils: Writing exception to parcel
    java.lang.SecurityException: Permission Denial: reading androidx.core.content.FileProvider uri content://com.example.name.provider/external_files/Android/data/com.example.name/files/allergy_report.pdf from pid=6005, uid=1000 requires the provider be exported, or grantUriPermission()
        at android.content.ContentProvider.enforceReadPermissionInner(ContentProvider.java:729)
        at android.content.ContentProvider$Transport.enforceReadPermission(ContentProvider.java:602)
        at android.content.ContentProvider$Transport.query(ContentProvider.java:231)
        at android.content.ContentProviderNative.onTransact(ContentProviderNative.java:104)
        at android.os.Binder.execTransactInternal(Binder.java:1021)
        at android.os.Binder.execTransact(Binder.java:994)

provider:

<provider
            android:name="androidx.core.content.FileProvider"
            android:authorities="${applicationId}.provider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/file_provider_paths" />
</provider>

file_provider_paths.xml

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="external_files" path="." />
</paths>

Sharing Intent

Intent intentShareFile = new Intent(Intent.ACTION_SEND);
        File fileWithinMyDir = new File(targetPdf);

        if(fileWithinMyDir.exists()) {
            intentShareFile.setType("application/pdf");
            Uri uri = FileProvider.getUriForFile(getActivity(), BuildConfig.APPLICATION_ID + ".provider", fileWithinMyDir);
            intentShareFile.putExtra(Intent.EXTRA_STREAM, uri);
            intentShareFile.putExtra(Intent.EXTRA_SUBJECT,
                    "Sharing File...");
            intentShareFile.putExtra(Intent.EXTRA_TEXT, "Sharing File...");
            intentShareFile.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
            startActivity(Intent.createChooser(intentShareFile, "Share File"));
        }

Hopefully you can point out my mistake why this exceptions is thrown when it seems like apps are granted permission properly and sharing works as it should be.

EDIT:

I found that the problem lies in line:

startActivity(Intent.createChooser(intentShareFile, "Share File"));

When I changed it simply to

startActivity(intentShareFile);

However it displays a little bit different layout for picking application. But still I cannot figure out why original chooser is not working.

回答1:

Sorry about the late response. I solved it like this:

Intent chooser = Intent.createChooser(intentShareFile, "Share File");

List<ResolveInfo> resInfoList = this.getPackageManager().queryIntentActivities(chooser, PackageManager.MATCH_DEFAULT_ONLY);

for (ResolveInfo resolveInfo : resInfoList) {
    String packageName = resolveInfo.activityInfo.packageName;
    this.grantUriPermission(packageName, uri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
}

startActivity(chooser);

This helped me: Permission Denial with File Provider through intent

来源：https://stackoverflow.com/questions/57689792/permission-denial-while-sharing-file-with-fileprovider