Cannot compile apk, Itext and Proguard conflict

Question

I'm developing an Android application, now I have to build an APK, to do this I follow this step:

1) Build -> Clean

2) Build -> Generate Signed APK

3) Jar Signature or Full APK Signature

But while the generation of the application an error occurs:

Information:Gradle tasks [:app:assembleRelease]
Warning:com.itextpdf.text.pdf.PdfEncryptor: can't find referenced class org.spongycastle.cms.jcajce.JceKeyTransEnvelopedRecipient
Warning:com.itextpdf.text.pdf.PdfEncryptor: can't find referenced class org.spongycastle.cms.RecipientInformation
Warning:com.itextpdf.text.pdf.PdfEncryptor: can't find referenced class org.spongycastle.cms.CMSException
Warning:com.itextpdf.text.pdf.PdfEncryptor: can't find referenced class org.spongycastle.cms.RecipientInformation
Warning:com.itextpdf.text.pdf.PdfEncryptor: can't find referenced class org.spongycastle.cms.Recipient
Warning:com.itextpdf.text.pdf.PdfPublicKeySecurityHandler: can't find referenced class org.spongycastle.asn1.DEROutputStream
Warning:com.itextpdf.text.pdf.PdfPublicKeySecurityHandler: can't find referenced class org.spongycastle.asn1.ASN1InputStream
Warning:com.itextpdf.text.pdf.PdfPublicKeySecurityHandler: can't find referenced class org.spongycastle.asn1.DEROctetString
Warning:com.itextpdf.text.pdf.PdfPublicKeySecurityHandler: can't find referenced class org.spongycastle.asn1.DERSet
Warning:com.itextpdf.text.pdf.PdfPublicKeySecurityHandler: can't find referenced class org.spongycastle.asn1.cms.RecipientInfo
Warning:com.itextpdf.text.pdf.PdfPublicKeySecurityHandler: can't find referenced class org.spongycastle.asn1.DERSet
Warning:com.itextpdf.text.pdf.PdfPublicKeySecurityHandler: can't find referenced class org.spongycastle.asn1.x509.AlgorithmIdentifier
Warning:com.itextpdf.text.pdf.PdfPublicKeySecurityHandler: can't find referenced class org.spongycastle.asn1.ASN1ObjectIdentifier
Warning:com.itextpdf.text.pdf.PdfPublicKeySecurityHandler: can't find referenced class org.spongycastle.asn1.x509.AlgorithmIdentifier
Warning:com.itextpdf.text.pdf.PdfPublicKeySecurityHandler: can't find referenced class org.spongycastle.asn1.cms.EncryptedContentInfo
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.asn1.tsp.MessageImprint
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.asn1.ASN1Sequence
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.cert.ocsp.BasicOCSPResp
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.cert.ocsp.SingleResp
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.cert.ocsp.CertificateID
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.operator.DigestCalculator
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.cert.ocsp.CertificateID
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.asn1.ASN1Sequence
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.asn1.ASN1TaggedObject
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.asn1.ASN1Sequence
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.asn1.ASN1OctetString
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.asn1.ASN1InputStream
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.asn1.ocsp.BasicOCSPResponse
Warning:com.itextpdf.text.pdf.security.PdfPKCS7: can't find referenced class org.spongycastle.tsp.TimeStampToken
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.SigPolicyQualifierInfo
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.pkcs.PKCSObjectIdentifiers
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.DERIA5String
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.SigPolicyQualifierInfo
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.SigPolicyQualifiers
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.SignaturePolicyIdentifier
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.SignaturePolicyId
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.DERObjectIdentifier
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.OtherHashAlgAndValue
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.x509.AlgorithmIdentifier
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.DEROctetString
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.OtherHashAlgAndValue
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.SignaturePolicyId
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.SignaturePolicyIdentifier
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.pkcs.PKCSObjectIdentifiers
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.SignaturePolicyIdentifier
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.SigPolicyQualifierInfo
Warning:com.itextpdf.text.pdf.security.SignaturePolicyInfo: can't find referenced class org.spongycastle.asn1.esf.SigPolicyQualifiers
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampRequestGenerator
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.asn1.ASN1ObjectIdentifier
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampRequestGenerator
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampRequest
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampResponse
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.asn1.cmp.PKIFailureInfo
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampResponse
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampToken
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampTokenInfo
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TSPException
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampRequest
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.asn1.cmp.PKIFailureInfo
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampToken
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampTokenInfo
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampRequestGenerator
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampRequest
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampResponse
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.asn1.cmp.PKIFailureInfo
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampToken
Warning:com.itextpdf.text.pdf.security.TSAClientBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampTokenInfo
Warning:com.itextpdf.text.pdf.security.TSAInfoBouncyCastle: can't find referenced class org.spongycastle.tsp.TimeStampTokenInfo
Warning:org.joda.convert.AbstractTypeStringConverter: can't find referenced class com.google.common.collect.ImmutableMap
Warning:org.joda.convert.AbstractTypeStringConverter: can't find referenced class com.google.common.collect.ImmutableMap$Builder
Warning:org.joda.convert.AbstractTypeStringConverter: can't find referenced class com.google.common.collect.ImmutableMap
Warning:org.joda.convert.AbstractTypeStringConverter: can't find referenced class com.google.common.collect.ImmutableMap$Builder
Warning:org.joda.convert.AbstractTypeStringConverter: can't find referenced class com.google.common.collect.ImmutableMap
Warning:org.joda.convert.TypeStringConverter: can't find referenced class com.google.common.reflect.TypeToken
Warning:org.joda.convert.TypeTokenStringConverter: can't find referenced class com.google.common.reflect.TypeToken
Warning:there were 823 unresolved references to classes or interfaces.
Warning:Exception while processing task java.io.IOException: Please correct the above warnings first.
Error:Execution failed for task ':app:transformClassesAndResourcesWithProguardForRelease'.
> Job failed, see logs for details
Information:BUILD FAILED

I don't know how to solve this problem.

What I have tried ?

I have put this code in my proguard-android file (located in \AppData\Local\Android\sdk\tools\proguard).

Rif

-keep class org.spongycastle.** { *; }
-dontwarn org.spongycastle.**

This solution doesn't work for me, the problem remains the same

**** CURRENT SOLUTION ****

Actually the only one solution that i found is set this value in the gradle:

1)shrinkResources false

2)minifyEnabled false

Answer 1

Try to put this in proguard-rules

-keep class com.itextpdf.** { *; }
-dontwarn com.itextpdf.**