IOException: not create document. Error

When I prepare the example "Display PDF in assets folder (inside APK)", I face with the error of "java.io.IOException: not create document. Error". It should be generated by the code:

pdfRenderer = new PdfRenderer(fileDescriptor);

Somebody commented it's caused by new version of Gradle (ref: https://github.com/googlesamples/android-PdfRendererBasic/issues/1), so I edit dependencies of buildscript in build.gradle (Project: ...), use gradle:2.1.2 to solve this problem.