As far as I know, there's no easy way to zoom in on a specific object. I don't have too much experience with views my self.
You'll need to do your math with these variables:
the player's x position (player.x)
the player's y position (player.y)
the view's x position (view_xview)
the view's y position (view_yview)
the view's width (view_wview)
the view's height (view_hview)