Java tutorial
/** * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. */ package com.ubergeek42.WeechatAndroid.utils; import android.app.Dialog; import android.content.DialogInterface; import android.os.Bundle; import android.support.annotation.NonNull; import android.support.v4.app.DialogFragment; import android.support.v7.app.AlertDialog; import android.support.v7.widget.AppCompatTextView; import android.text.Html; import android.widget.ScrollView; import android.widget.TextView; import com.ubergeek42.WeechatAndroid.R; import com.ubergeek42.WeechatAndroid.WeechatActivity; import com.ubergeek42.WeechatAndroid.service.SSLHandler; import org.apache.commons.codec.binary.Hex; import org.apache.commons.codec.digest.DigestUtils; import java.security.cert.CertificateEncodingException; import java.security.cert.X509Certificate; import java.text.DateFormat; public class UntrustedCertificateDialog extends DialogFragment { X509Certificate certificate; public static UntrustedCertificateDialog newInstance(X509Certificate certificate) { UntrustedCertificateDialog d = new UntrustedCertificateDialog(); d.certificate = certificate; d.setRetainInstance(true); return d; } public UntrustedCertificateDialog() { } // this can get called before the activity has started @NonNull @Override public Dialog onCreateDialog(Bundle savedInstanceState) { final int padding = (int) getResources().getDimension(R.dimen.dialog_padding_full); final ScrollView scrollView = new ScrollView(getContext()); final TextView textView = new AppCompatTextView(getContext()); textView.setText(Html.fromHtml(getCertificateDescription())); scrollView.addView(textView); return new AlertDialog.Builder(getContext()).setTitle(getString(R.string.ssl_cert_dialog_title)) .setView(scrollView, padding, padding / 2, padding, 0) .setPositiveButton(getString(R.string.ssl_cert_dialog_accept_button), new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { SSLHandler.getInstance(getContext()).trustCertificate(certificate); ((WeechatActivity) getActivity()).connect(); } }) .setNegativeButton(getString(R.string.ssl_cert_dialog_reject_button), null).create(); } // this prevents the dialog from being dismissed on activity restart // see https://code.google.com/p/android/issues/detail?id=17423 @Override public void onDestroyView() { if (getDialog() != null && getRetainInstance()) { getDialog().setDismissMessage(null); } super.onDestroyView(); } public String getCertificateDescription() { String fingerprint; try { fingerprint = new String(Hex.encodeHex(DigestUtils.sha256(certificate.getEncoded()))); } catch (CertificateEncodingException e) { fingerprint = getString(R.string.ssl_cert_dialog_unknown_fingerprint); } return getString(R.string.ssl_cert_dialog_description, certificate.getSubjectDN().getName(), certificate.getIssuerDN().getName(), DateFormat.getDateTimeInstance().format(certificate.getNotBefore()), DateFormat.getDateTimeInstance().format(certificate.getNotAfter()), fingerprint); } }