How to hide angular-strap $alert

I have this code and on socket.connect I want to be able to hide the alert that was shown in socket.disconnect.

I see there is a reference in the docs to $scope methods hide, show, and toggle but how can I use them in this example?

socket.on('disconnect', function () {

  // Show login error message
  $alert({
    title: 'Connection lost.',
    content: 'Please reload the page.',
    placement: 'top-right',
    type: 'danger',
    show: true
  });
});

socket.on('connect', function () {
  // TODO: Check if connection alert is showing and if it is, hide it
});