$ionicLoading dynamic content

Hello,
i would like to use the $ionicLoading as a countdown before the mainscreen is useable.
Currently iam using the duration option to autohide after some seconds, but i want to show the remaining seconds on the loading screen.
Does anyone has an idea how to display the remaining time on the loading screen?
First i was thinking i can use the setContent() function, but this is deprecated. Any thoughts?
Thanks