Gets a value that represents the horizontal size of the area that can be scrolled; the difference between the height of the extent and the height of the viewport.
Gets a value that represents the vertical size of the area that can be scrolled; the difference between the width of the extent and the width of the viewport.
Gets or sets a coeficient which will determine in each layout pass the size of the viewport. If zero is specified the size of the viewport will be equal to the scrollviewer viewport. If 0.5 is specified the size of the viewport will be enlarged to take up half screen more at both sides of the original viewport.