void close()

Stop interacting with the text input control.

After calling this method, the text input control might disappear if no other client attaches to it within this animation frame.

Source 

void close() {
  if (attached) {
    PlatformMessages.invokeMethod(_kChannelName, 'TextInput.clearClient');
    _clientHandler
      .._currentConnection = null
      .._scheduleHide();
  }
  assert(!attached);
}