I'm trying, but I always get an error:
java.lang.UnsatisfiedLinkError: Native method not found: com.shockwave.pdfium.PdfiumCore.nativeOpenDocument

ILjava/lang/String

J
at com.shockwave.pdfium.PdfiumCore.nativeOpenDocument(Native Method)
at com.shockwave.pdfium.PdfiumCore.newDocument(PdfiumCore.java:135)
at com.shockwave.pdfium.PdfiumCore.newDocument(PdfiumCore.java:127)
at de.donmanfred.PdfiumCorewrapper.newDocument(PdfiumCorewrapper.java:52)
at b4a.example.main._activity_create(main.java:388)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at anywheresoftware.b4a.shell.Shell.runMethod(Shell.java:710)
at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:342)
at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:249)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:139)
at b4a.example.main.afterFirstLayout(main.java:102)
at b4a.example.main.access$000(main.java:17)
at b4a.example.main$WaitForLayout.run(main.java:80)
at android.os.Handler.handleCallback(Handler.java:725)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5041)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
at dalvik.system.NativeStart.main(Native Method)
** Activity (main) Resume **