SORRY one more thing missing

hi,
sorry for posting so many threads but this is the last thing.
my game will be in a sight from the top and a bit to the side like cinderfall or diablo if you know
well
what do i do so that it scrolls?
i dont only want to know that i also want to know how to do so that when you walk against a building it stops scrolling(thats my main problem)
i normally do a code like this:
if (key.isDown(Key.RIGHT)
_root._x+=10
}
}
this does so that the screen scrolls when im walking(if something is wrong in the code its just an example
well,when i walk against a building it still scrolls(if im still pressing the button for the man to walk)but the man stays there because i did a code so that he doesnt go through the building.how do i do so that it stops scrolling when im walking against the building?
please help
if you dont understand just ask what you dont understand
thanks