webView.setWebViewClient(new WebViewClient() { 
 
  @Override 
  public void onReceivedSslError(WebView view, SslErrorHandler handler, SslError error) { 
    super.onReceivedSslError(view, handler, error); 
  } 
} 

  /**
   * SSL证书错误，手动校验https证书
   *
   * @param cert   https证书
   * @param sha256Str sha256值
   * @return true通过，false失败
   */
  public static boolean isSSLCertOk(SslCertificate cert, String sha256Str) {
    byte[] SSLSHA256 = hexToBytes(sha256Str);
    Bundle bundle = SslCertificate.saveState(cert);
    if (bundle != null) {
      byte[] bytes = bundle.getByteArray("x509-certificate");
      if (bytes != null) {
        try {
          CertificateFactory cf = CertificateFactory.getInstance("X.509");
          Certificate ca = cf.generateCertificate(new ByteArrayInputStream(bytes));
          MessageDigest sha256 = MessageDigest.getInstance("SHA-256");
          byte[] key = sha256.digest(((X509Certificate) ca).getEncoded());
          return Arrays.equals(key, SSLSHA256);
        } catch (Exception e) {
          e.printStackTrace();
        }
      }
    }
    return false;
  }

  /**
   * hexString转byteArr
   * <p>例如：</p>
   * hexString2Bytes("00A8") returns { 0, (byte) 0xA8 }
   *
   * @param hexString
   * @return 字节数组
   */
  public static byte[] hexToBytes(String hexString) {

    if (hexString == null || hexString.trim().length() == 0)
      return null;

    int length = hexString.length() / 2;
    char[] hexChars = hexString.toCharArray();
    byte[] bytes = new byte[length];
    String hexDigits = "0123456789abcdef";
    for (int i = 0; i < length; i++) {
      int pos = i * 2; // 两个字符对应一个byte
      int h = hexDigits.indexOf(hexChars[pos]) << 4; // 注1
      int l = hexDigits.indexOf(hexChars[pos + 1]); // 注2
      if (h == -1 || l == -1) { // 非16进制字符
        return null;
      }
      bytes[i] = (byte) (h | l);
    }
    return bytes;
  }

webView.setWebViewClient(new WebViewClient() {
 @Override
 public void onReceivedSslError(WebView view, SslErrorHandler handler, SslError error) {
  super.onReceivedSslError(view, handler, error);
  if (error.getPrimaryError() == SslError.SSL_INVALID) {
   // 如果手动校验sha256成功就允许加载页面
   if (SSLCertUtil.isSSLCertOk(error.getCertificate(), "6683c9584b8287ec3a50e312f4a540c79938aaeb76bd02e40a9ca037ee5d24f4")) {
    handler.proceed();
   } else {
    try {
     new AlertDialog.Builder(MainActivity.this)
       .setTitle("警告")
       .setMessage("证书校验失败")
       .setPositiveButton("退出", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
         System.exit(0);
         dialog.dismiss();
        }
       }).show();
    } catch (Exception e) {
     e.printStackTrace();
    }
   }
  } else {
   handler.cancel();
  }
 }
});

/**
 * The certificate is not yet valid
 */
public static final int SSL_NOTYETVALID = 0;
/**
 * The certificate has expired
 */
public static final int SSL_EXPIRED = 1;
/**
 * Hostname mismatch
 */
public static final int SSL_IDMISMATCH = 2;
/**
 * The certificate authority is not trusted
 */
public static final int SSL_UNTRUSTED = 3;
/**
 * The date of the certificate is invalid
 */
public static final int SSL_DATE_INVALID = 4;
/**
 * A generic error occurred
 */
public static final int SSL_INVALID = 5;