Evans Straight Line linkage is one of the application of Four Bar Linkage. Evans straight line linkage does not obey Grashof's law. In this case crank can't make a complete revolution. Therefore this is a rocker mechanism.
This animation is derived from Four Bar Linkage. to demonstrate Evans Straight Line linkage. You can do everything yo do in Four Bar Linkage, however due to some internal constrains you may have some problems. I advise to use Four Bar Linkage instead.