Get the bounding box of the current area shown in arcgis MapView

Question

in our android app we are displaying markers on a map based on the ArcGIS Maps SDK.

I now want to update the markers every time the user navigates in the map. So my question are:

• How am I informed when the user navigates the map?
• Is there something like a "bounding box" class to store the view?

Thanks for your help!