Open downloaded file on Android N using FileProvider

Thanks to @greenaps I was able to solve the issue. The local URI retrieved from the DownlodManager was prefixed with file://. This has to be dropped for the new FileProvider:

if (localUri.substring(0, 7).matches("file://")) {
    localUri =  localUri.substring(7);
}
File file = new File(localUri);

here change in AndroidManifest.xml

<provider
    android:name="android.support.v4.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_paths"/>
</provider>

change in file path

Uri contentUri;
if(Build.VERSION.SDK_INT == 24){
         contentUri = FileProvider.getUriForFile(MainActivity.this,
              getApplicationContext().getPackageName() + ".provider",
                    file);
 } else{
         contentUri = Uri.fromFile(file);
        }