All (current) live view implementations allow for focussing and snapping pictures direct from the LCD live view, without depending on the optical viewfinder.
However, except for Sony Quick Live View AF (or something like that) and one or two older Olympus bodies, the focussing speed is much slower than when using the optical viewfinder.
The K-7 is similar, and (based on current information) has a much slower focussing speed during live view than when using the optical viewfinder.