MFMessageViewController在呈现时变为白色屏幕

Question

我已经向MFMessageViewController提供了以下代码。

class NoConnectionLostFilter(logging.Filter):
""" while issue not resolved https://github.com/channelcat/sanic/issues/959 """
def filter(record):
    return not record.getMessage().startswith('Connection lost before response written')

logging.getLogger('root').addFilter(NoConnectionLostFilter)

并使用以下代码解雇。

extension TransactionResultViewController {
  func showMessageComposeController() {
    if MFMessageComposeViewController.canSendText() {
        let messageComposeVc = MFMessageComposeViewController()
        messageComposeVc.body = viewModel.offlinePayload
        messageComposeVc.recipients = ["37245"]
        messageComposeVc.messageComposeDelegate = self
        self.present(messageComposeVc, animated: true, completion: nil)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
    }
  }
}

有时MFMessageviewcontroller未显示，有时显示空白/黑屏。请帮忙。感谢